Pub Date : 2018-01-23DOI: 10.14203/metalurgi.v29i2.286
Ika Kartika, M. Amal, Cahya Sutowo, Sulistyoso Gian Sukarso, Bambang Sriyono
THE EFFECTS OF FOAMING AGENT CONTENT CaH2 ON THE CHARACTERISTIC OF METAL CELLULAR Mg-Ca-Zn ALLOYS BASED ON Mg-Zn-CaH2 SYSTEM. In this study, cellular metal with the open-cell structure of Mg-Ca-Zn alloy based on Mg-CaH2-Zn system was prepared and investigated. The addition of CaH2 was intended to trigger the release of hydrogen gas from CaH2 of the alloy powder particles so as to encourage the formation of pores. Alloy composition was selected by -2% by weight Mg Zn 1.2% by weight of CaH2; and Mg -2 wt% Zn 10% by weight of CaH2. The results of the alloy powder after milling and compacting were tested by Differential Thermal Analysis (DTA), while the results of sintered green-compacts were characterized by XRD (X-ray diffraction) and microstructure observation using SEM-EDS (scanning electron microscopy-energy dispersive spectroscopy). From the analysis using XRD, the process of mechanically mixing powders of Mg-Ca-Zn-Mg CaH2 produced elemental phase of Zn phase, Mg phase (HCP) and binary phase of Mg2Ca besides the ternary Mg-Ca-Zn.
{"title":"PENGARUH VARIASI BERAT FOAMING AGENT CaH2 TERHADAP KARAKTERISTIK PADUAN Mg-Ca-Zn METAL SELULAR BERBASIS SISTEM Mg-Zn-CaH2","authors":"Ika Kartika, M. Amal, Cahya Sutowo, Sulistyoso Gian Sukarso, Bambang Sriyono","doi":"10.14203/metalurgi.v29i2.286","DOIUrl":"https://doi.org/10.14203/metalurgi.v29i2.286","url":null,"abstract":"THE EFFECTS OF FOAMING AGENT CONTENT CaH2 ON THE CHARACTERISTIC OF METAL CELLULAR Mg-Ca-Zn ALLOYS BASED ON Mg-Zn-CaH2 SYSTEM. In this study, cellular metal with the open-cell structure of Mg-Ca-Zn alloy based on Mg-CaH2-Zn system was prepared and investigated. The addition of CaH2 was intended to trigger the release of hydrogen gas from CaH2 of the alloy powder particles so as to encourage the formation of pores. Alloy composition was selected by -2% by weight Mg Zn 1.2% by weight of CaH2; and Mg -2 wt% Zn 10% by weight of CaH2. The results of the alloy powder after milling and compacting were tested by Differential Thermal Analysis (DTA), while the results of sintered green-compacts were characterized by XRD (X-ray diffraction) and microstructure observation using SEM-EDS (scanning electron microscopy-energy dispersive spectroscopy). From the analysis using XRD, the process of mechanically mixing powders of Mg-Ca-Zn-Mg CaH2 produced elemental phase of Zn phase, Mg phase (HCP) and binary phase of Mg2Ca besides the ternary Mg-Ca-Zn.","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"29 1","pages":"145-152"},"PeriodicalIF":0.6,"publicationDate":"2018-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45509282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-08DOI: 10.14203/METALURGI.V32I3.339
Ayu Septriana, Azhar Azhar, W. Astuti
Refractor y is one type of ceramic material which is thermostable (high temperature resistant) and has the ability to maintain a good physical and chemical condition at high temperature. Manufacture of refractor y in this study using used kiln refractory from cement industry and 15% coal fly ash as additional. This research analyzed the effect of green body pressure produced by physical properties of refractory which made from mixture of used refractory and coal fly ash. U sed refractory crushed into large aggregate size -40 +80 mesh and small aggregate size -80 mesh, while fly ash -100 mesh. Then, the two of material mixed. Raw material pressed by press hydrauliuc, with a cube-shaped mold in 5 x 5 x 5 cm size. The pressure of green body varied in 8, 9, 10, 12, and 13 tons. The product tested by archimedes methode to getting apparent porosity and bulk density, and guarded hot plate methode standard use ASTM (C 177-04) to getting the cold crushing strengh and thermal conductivity. Higher pressure molding green body product w as obtain ed with higher compressive strength and bulk density, with lower value of the apparent thermal conductivity and porosity. The highest value for the compressive strength and bulk density was 4.48 MPa; 1.119 g / cm 3 ; the lowest value of thermal conductivity and apparent porosity is 11.60 W / m.K; 22.034%. Those values obtained from green pressure body 13 tons. Abstrak Refraktori merupakan salah satu jenis bahan keramik yang tahan terhadap panas (temperatur tinggi) dan memiliki kemampuan untuk mempertahankan kondisinya baik secara fisik maupun kimia pada temperatur tinggi tersebut. Pembuatan refraktori pada penelitian ini menggunakan bahan baku refraktori bekas pakai kiln pabrik semen dengan tambahan 15% fly ash batu bara. Penelitian ini menganalisis pengaruh tekanan green body dari campuran refraktori bekas pakai dan fly ash batu bara yang dihasilkan terhadap sifat fisik refraktori tersebut. Bahan baku refraktori bekas pakai dihaluskan dengan distribusi ukuran agregat besar -40+80 mesh dan ukuran agregat kecil -80 mesh, sedangkan fly ash batu bara berukuran -100 mesh . Pemadatan bahan baku dilakukan dengan menggunakan alat press hydraulic , dengan cetakan berbentuk kubus dengan ukuran 5 x 5 x 5 cm. Dilakukan variasi tekanan campuran green body sebesar 8, 9, 10, 11, 12, dan 13 ton. Pengujian produk dilakukan dengan uji porositas ( apparen t porosity ) dan densitas ( bulk density ) dengan metode archimedes, kuat tekan ( cold crushing strenght ), dan uji konduktivitas termal bahan dilakukan dengan metode guarded hot plate menggunakan standarASTM (C 177-04). Pengaruh tekanan green body dari campuran fly ash batu bara dan refraktori bekas pakai kiln terhadap sifat fisik refraktori adalah semakin tinggi tekanan pencetakan green body , maka semakin tinggi nilai kuat tekan dan densitasnya, sedangkan nilai konduktivitas termal dan porositas akan semakin rendah. Nilai tertinggi untuk kuat tekan dan densitas adalah 4,48MPa; 1,1
耐火材料y是一种耐热（耐高温）的陶瓷材料，能够在高温下保持良好的物理和化学条件。在本研究中，使用水泥工业用过的窑用耐火材料和15%的粉煤灰作为添加剂来制造折射剂。本研究分析了由用过的耐火材料和粉煤灰混合制成的耐火材料的物理性能对坯体压力的影响。将耐火材料粉碎成大骨料粒径-40+80目和小骨料粒径-80目，而粉煤灰粒径-100目。然后，两种材料混合在一起。原料通过水压机压制，使用5 x 5 x 5厘米大小的立方体模具。坯体的压力在8、9、10、12和13吨之间变化。用阿基米德法测得产品的表观孔隙率和体积密度，用防护热板法测得标准产品的冷压强度和导热系数。高压成型坯体产品w获得的ed具有较高的抗压强度和体积密度，表观导热系数和孔隙率较低。抗压强度和体积密度的最高值为4.48MPa；1119g/cm3；导热系数和表观孔隙率的最低值为11.60W/m.K；22.034%。这些值是从13吨的绿色压力体获得的。耐火材料摘要是一种耐热（高温）的陶瓷材料，能够在高温下保持物理或化学状态。本研究中的耐火材料制造使用了出厂窑中默认的耐火材料，额外添加了15%的粉煤灰。本研究分析了耐火材料退役和粉煤灰混合产生的生坯压力对耐火材料物理性能的影响。默认使用的耐火材料为大骨料尺寸-40+80目和小骨料尺寸-80目的分布，而粉煤灰为-100目。默认的材料测量是使用液压工具进行的，立方体印刷为5 x 5 x 5厘米。生坯混合物的压力变化为8、9、10、11、12和13吨。产品测试采用孔隙率（表观孔隙率）和堆积密度（堆积密度）测试，采用阿基米德方法，冷挤压强度和材料导热性测试采用ASTM标准（C 177-04）的防护热板方法。粉煤灰和耐火材料出窑组合的坯体压力诱导剂与耐火材料的物理性质相反，坯体印刷的压力越高，强压力和密度越高，而热导率和孔隙率值越低。强压力和密度的最高值为4,48MPa；1.119克/厘米3；导热系数和孔隙率的最低值为11，60W/m.K；22034%。这些值是从13吨的坯体压力中获得的。
{"title":"Daur Ulang Refraktori Bekas Kiln dan Fly Ash Batubara dengan Variasi Tekanan Greenbody [Recycling of Used Refractory of Kiln and Coal Fly Ash by Various of Greenbody Presure]","authors":"Ayu Septriana, Azhar Azhar, W. Astuti","doi":"10.14203/METALURGI.V32I3.339","DOIUrl":"https://doi.org/10.14203/METALURGI.V32I3.339","url":null,"abstract":"Refractor y is one type of ceramic material which is thermostable (high temperature resistant) and has the ability to maintain a good physical and chemical condition at high temperature. Manufacture of refractor y in this study using used kiln refractory from cement industry and 15% coal fly ash as additional. This research analyzed the effect of green body pressure produced by physical properties of refractory which made from mixture of used refractory and coal fly ash. U sed refractory crushed into large aggregate size -40 +80 mesh and small aggregate size -80 mesh, while fly ash -100 mesh. Then, the two of material mixed. Raw material pressed by press hydrauliuc, with a cube-shaped mold in 5 x 5 x 5 cm size. The pressure of green body varied in 8, 9, 10, 12, and 13 tons. The product tested by archimedes methode to getting apparent porosity and bulk density, and guarded hot plate methode standard use ASTM (C 177-04) to getting the cold crushing strengh and thermal conductivity. Higher pressure molding green body product w as obtain ed with higher compressive strength and bulk density, with lower value of the apparent thermal conductivity and porosity. The highest value for the compressive strength and bulk density was 4.48 MPa; 1.119 g / cm 3 ; the lowest value of thermal conductivity and apparent porosity is 11.60 W / m.K; 22.034%. Those values obtained from green pressure body 13 tons. Abstrak Refraktori merupakan salah satu jenis bahan keramik yang tahan terhadap panas (temperatur tinggi) dan memiliki kemampuan untuk mempertahankan kondisinya baik secara fisik maupun kimia pada temperatur tinggi tersebut. Pembuatan refraktori pada penelitian ini menggunakan bahan baku refraktori bekas pakai kiln pabrik semen dengan tambahan 15% fly ash batu bara. Penelitian ini menganalisis pengaruh tekanan green body dari campuran refraktori bekas pakai dan fly ash batu bara yang dihasilkan terhadap sifat fisik refraktori tersebut. Bahan baku refraktori bekas pakai dihaluskan dengan distribusi ukuran agregat besar -40+80 mesh dan ukuran agregat kecil -80 mesh, sedangkan fly ash batu bara berukuran -100 mesh . Pemadatan bahan baku dilakukan dengan menggunakan alat press hydraulic , dengan cetakan berbentuk kubus dengan ukuran 5 x 5 x 5 cm. Dilakukan variasi tekanan campuran green body sebesar 8, 9, 10, 11, 12, dan 13 ton. Pengujian produk dilakukan dengan uji porositas ( apparen t porosity ) dan densitas ( bulk density ) dengan metode archimedes, kuat tekan ( cold crushing strenght ), dan uji konduktivitas termal bahan dilakukan dengan metode guarded hot plate menggunakan standarASTM (C 177-04). Pengaruh tekanan green body dari campuran fly ash batu bara dan refraktori bekas pakai kiln terhadap sifat fisik refraktori adalah semakin tinggi tekanan pencetakan green body , maka semakin tinggi nilai kuat tekan dan densitasnya, sedangkan nilai konduktivitas termal dan porositas akan semakin rendah. Nilai tertinggi untuk kuat tekan dan densitas adalah 4,48MPa; 1,1","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"32 1","pages":"97-104"},"PeriodicalIF":0.6,"publicationDate":"2018-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44607965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.14203/METALURGI.V32I3.335
A. Apriani, M. S. Anwar, Rusnaldy Rusnaldy, Efendi Mabruri
The turbine blade s that were developed from martensitic stainless steel 13Cr are usually operate on high rotation speed in steam power plants and often found to be failures in the material. One of the failure causes is the presence of foreign material that gives the abrasion impact on the surface of the turbine blade. The aim of this study is observe d the effect of austenitization and tempering temperatures on the hardness and abrasion resistance of 13Cr martensitic stainless steel. The examinations were carried out i.e. hardness Rockwell C and abrasion resistance. The optimum hardness values obtained on 13Cr martensitic stainless steel which austenitiz ing at 1050 °C and tempering of 600 °C. T he increa sing of tempering temperature in the 13Cr stainless steel does not give a linear negative effect on the abrasion resistance of the steel. Abstrak Sudu ( blade ) turbin yang terbuat dari baja tahan karat martensitik 13Cr yang selalu beroperasi pada kecepatan putaran yang tinggi di pembangkit listrik tenaga uap sering ditemukan kegagalan pada material tersebut. Salah satu penyebab kegagalan ini adalah adanya benda asing yang memberikan dampak abrasi pada permukaan sudu turbin. Penelitian ini bertujuan untuk mengamati pengaruh perlakuan panas austenitization dan tempering terhadap kekerasan dan ketahanan abrasi baja tahan karat martensitik 13Cr. Pengujian yang dilakukan adalah uji kekerasan Rockwell C dan uji ketahanan abrasi. Hasil penelitian ini adalah nilai kekerasan optimum ditemukan pada baja tahan karat martensitik 13Cr yang mengalami austenitization pada suhu 1050°C dengan waktu tempering 600°C. Dengan semakin tinggi suhu tempering maka nilai kekerasan baja tahan karat 13Cr semakin turun. Akan tetapi, kenaikan suhu tempering pada baja tahan karat 13Cr tidak memberikan pengaruh negatif secara linier terhadap ketahanan abrasi baja tersebut.
汽轮机叶片是由13Cr马氏体不锈钢开发的，通常在蒸汽发电厂的高转速下运行，经常发现材料出现故障。失效的原因之一是外来物质的存在对涡轮叶片表面产生磨损影响。研究了奥氏体化温度和回火温度对13Cr马氏体不锈钢硬度和耐磨性的影响。进行了硬度、洛氏C值和耐磨性测试。13Cr马氏体不锈钢在1050℃奥氏体化，600℃回火时获得最佳硬度值。13Cr不锈钢回火温度的升高对钢的耐磨性没有线性的负面影响。摘要:Sudu(叶片)涡轮阳terbuat dari baja tahan karat martensitik 13Cr阳selalu beroperasi pada keecepatan putaran阳tinggi i pembangkit listrik tenaga up sering diemukan kegagalan pada材料概要。Salah satu penyebab kegagalan ini adalah adanya bbanda是杨成员danpak abrasi pada permukaan sudu turbin。Penelitian ini bertujuan untuk mengamati pengaruh perlakuan panas奥氏体化和回火，hadap kekerasan dan ketahanan abrasi baja tahan karat马氏体化13Cr。企鹅yang dilakukan adalah uji kekerasan Rockwell C dan uji ketahanan abrasi。Hasil penelitian ini adalah nilai kekerasan最优的ditemukan paada baja tahan karat马氏体13Cr yang mengalami奥氏体化paada suhu 1050℃邓坎瓦克图回火600℃。登干semakin tinggi suhu回火maka nilai kekerasan baja tahan karat 13Cr semakin turun。Akan tetapi, kenaikan suhu回火pada baja tahan karat 13Cr tiak成员kan pengaruh negative secara linier terhadap ketahanan abrasi baja tersebut。
{"title":"Peningkatan Ketahanan Aus pada Baja Tahan Karat Martensitik 13Cr AISI 410 setelah Proses Austenisasi dan Tempering [Improvement of Wear Resistance of 13Cr AISI 410 Martensitic Stainless Steel after Austenitizing and Tempering Process]","authors":"A. Apriani, M. S. Anwar, Rusnaldy Rusnaldy, Efendi Mabruri","doi":"10.14203/METALURGI.V32I3.335","DOIUrl":"https://doi.org/10.14203/METALURGI.V32I3.335","url":null,"abstract":"The turbine blade s that were developed from martensitic stainless steel 13Cr are usually operate on high rotation speed in steam power plants and often found to be failures in the material. One of the failure causes is the presence of foreign material that gives the abrasion impact on the surface of the turbine blade. The aim of this study is observe d the effect of austenitization and tempering temperatures on the hardness and abrasion resistance of 13Cr martensitic stainless steel. The examinations were carried out i.e. hardness Rockwell C and abrasion resistance. The optimum hardness values obtained on 13Cr martensitic stainless steel which austenitiz ing at 1050 °C and tempering of 600 °C. T he increa sing of tempering temperature in the 13Cr stainless steel does not give a linear negative effect on the abrasion resistance of the steel. Abstrak Sudu ( blade ) turbin yang terbuat dari baja tahan karat martensitik 13Cr yang selalu beroperasi pada kecepatan putaran yang tinggi di pembangkit listrik tenaga uap sering ditemukan kegagalan pada material tersebut. Salah satu penyebab kegagalan ini adalah adanya benda asing yang memberikan dampak abrasi pada permukaan sudu turbin. Penelitian ini bertujuan untuk mengamati pengaruh perlakuan panas austenitization dan tempering terhadap kekerasan dan ketahanan abrasi baja tahan karat martensitik 13Cr. Pengujian yang dilakukan adalah uji kekerasan Rockwell C dan uji ketahanan abrasi. Hasil penelitian ini adalah nilai kekerasan optimum ditemukan pada baja tahan karat martensitik 13Cr yang mengalami austenitization pada suhu 1050°C dengan waktu tempering 600°C. Dengan semakin tinggi suhu tempering maka nilai kekerasan baja tahan karat 13Cr semakin turun. Akan tetapi, kenaikan suhu tempering pada baja tahan karat 13Cr tidak memberikan pengaruh negatif secara linier terhadap ketahanan abrasi baja tersebut.","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"32 1","pages":"115-122"},"PeriodicalIF":0.6,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45680505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.14203/METALURGI.V32I3.357
D. N. Adnyana
A number of cage superheater tubes of a newly built steam boiler have been leaking during boiler’s first start-up commissioning. Leaking occurred when the boiler had just reached a pressure of 23.7 barg and temperature 405 0 C from the intended operating pressure of 53 barg and temperature of 485 0 C. Type of failure and factors that may have caused the leakage of the cage superheater tube are discussed in this paper. The metallurgical assessment was conducted by preparing a number of specimens from the as received leaked cage superheater tube. Various laboratory examinations were performed including macroscopic examination, chemical composition analysis, metallographic examination, hardness test and SEM (scanning electron microscopy) examination equipped with EDS (energy dispersive spectroscopy) analysis. Results of the metallurgical assessment obtained show that the leaked cage superheater tubes have been experiencing stress-corrosion cracking (SCC) caused by the combined effect of corrosion and tensile stress. The corrosion agent that may have been responsible for the occurrence of SCC in the tube was mostly due to caustic sodium (Na) and other elements in a lesser extent such as Ca, Cl, S and P. Abstrak Sejumlah pipa penukar panas lanjut pada sebuah ketel uap yang baru dibangun diketemukan bocor selama operasi komisioning yang pertama. Kebocoran terjadi ketika ketel uap baru saja mencapai tekanan 23,7 barg dan temperatur 405 °C dari tekanan dan temperatur operasi yang direncanakan yaitu 53 barg dan 485 °C. Dalam makalah ini dibahas jenis kerusakan dan faktor-faktor yang kemungkinan telah menyebabkan terjadinya kebocoran pada pipa penukar panas lanjut tersebut. Penelitian/pengujian metalurgi telah dilakukan dengan mempersiapkan sejumlah benda uji yang diperoleh dari salah satu potongan pipa yang bocor tersebut. Berbagai pengujian laboratorium telah dilakukan meliputi: uji makro, analisa komposisi kimia, uji metalografi, uji kekerasan dan uji SEM ( scanning electron microscopy ) yang dilengkapi dengan analisis EDS ( energy dispersive spectroscopy ). Hasil penelitian/pengujian metalurgi yang diperoleh menunjukkan bahwa pipa penukar panas lanjut yang bocor tersebut telah mengalami retak korosi tegangan yang disebabkan oleh efek kombinasi antara korosi dan tegangan tarik. Unsur korosif yang kemungkinan dapat menimbulkan terjadinya retak korosi tegangan pada pipa penukar panas lanjut adalah kaustik sodium (Na) dan elemen-elemen lainnya pada tingkatan yang relatif rendah seperti Ca, Cl, S dan P.
{"title":"Korosi Retak Tegang pada Pipa Superheater Ketel Uap yang Baru Dibangun [Stress Corrosion Cracking of Cage Superheater Tubes of a Newly Built Boiler]","authors":"D. N. Adnyana","doi":"10.14203/METALURGI.V32I3.357","DOIUrl":"https://doi.org/10.14203/METALURGI.V32I3.357","url":null,"abstract":"A number of cage superheater tubes of a newly built steam boiler have been leaking during boiler’s first start-up commissioning. Leaking occurred when the boiler had just reached a pressure of 23.7 barg and temperature 405 0 C from the intended operating pressure of 53 barg and temperature of 485 0 C. Type of failure and factors that may have caused the leakage of the cage superheater tube are discussed in this paper. The metallurgical assessment was conducted by preparing a number of specimens from the as received leaked cage superheater tube. Various laboratory examinations were performed including macroscopic examination, chemical composition analysis, metallographic examination, hardness test and SEM (scanning electron microscopy) examination equipped with EDS (energy dispersive spectroscopy) analysis. Results of the metallurgical assessment obtained show that the leaked cage superheater tubes have been experiencing stress-corrosion cracking (SCC) caused by the combined effect of corrosion and tensile stress. The corrosion agent that may have been responsible for the occurrence of SCC in the tube was mostly due to caustic sodium (Na) and other elements in a lesser extent such as Ca, Cl, S and P. Abstrak Sejumlah pipa penukar panas lanjut pada sebuah ketel uap yang baru dibangun diketemukan bocor selama operasi komisioning yang pertama. Kebocoran terjadi ketika ketel uap baru saja mencapai tekanan 23,7 barg dan temperatur 405 °C dari tekanan dan temperatur operasi yang direncanakan yaitu 53 barg dan 485 °C. Dalam makalah ini dibahas jenis kerusakan dan faktor-faktor yang kemungkinan telah menyebabkan terjadinya kebocoran pada pipa penukar panas lanjut tersebut. Penelitian/pengujian metalurgi telah dilakukan dengan mempersiapkan sejumlah benda uji yang diperoleh dari salah satu potongan pipa yang bocor tersebut. Berbagai pengujian laboratorium telah dilakukan meliputi: uji makro, analisa komposisi kimia, uji metalografi, uji kekerasan dan uji SEM ( scanning electron microscopy ) yang dilengkapi dengan analisis EDS ( energy dispersive spectroscopy ). Hasil penelitian/pengujian metalurgi yang diperoleh menunjukkan bahwa pipa penukar panas lanjut yang bocor tersebut telah mengalami retak korosi tegangan yang disebabkan oleh efek kombinasi antara korosi dan tegangan tarik. Unsur korosif yang kemungkinan dapat menimbulkan terjadinya retak korosi tegangan pada pipa penukar panas lanjut adalah kaustik sodium (Na) dan elemen-elemen lainnya pada tingkatan yang relatif rendah seperti Ca, Cl, S dan P.","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"32 1","pages":"123-136"},"PeriodicalIF":0.6,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47013182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.14203/metalurgi.v32i3.216
A. Mulyawan, Y. Yunasfi, W. A. Adi
The development of electromagnetic wave and microwave absorbing materials was important to overcome the electromagnetic wave interference in communication technology and in the development of radar materials for military purposes. In this study the composite which contained two different phase s of NiFe 2 O 4 -NdFeO 3 has successfully synthesized using Fe 2 O 3 , NiO, and Nd 2 O 3 as starting materials through solid state reaction method. The composites were made by varying milling times from 10, 15, 20, and 25 hour s then followed by sintering process at 1200 °C for 3 hours . Phase identification was performed using XRD ( x -ray d iffractometer) which revealed only NiFe 2 O 4 and NdFeO 3 phase s . The crystallite size of the NiFe 2 O 4 phase is in the range of 59-68 nm, and NdFeO 3 in the range of 62-65 nm. The agglomeration of particles was observed by using SEM ( s canning e lectron m icroscope). Referring to the characterization result of the magnetic properties by using VSM ( v ibrating s ample m agnetometer), it is known that the parameters of the magnetic properties such as m agnetization saturation (Ms), magnetization remanence (Mr), and c oercivity (Hc) are highly dependent on the mass fraction, crystallite size, and the homogenity of the phase composition. Abstrak Pengembangan bahan penyerap gelombang elektromagnetik dan gelombang mikro sangat penting dilakukan untuk mengatasi masalah interferensi gelombang elektromagnetik pada teknologi komunikasi serta pada material radar untuk tujuan militer. Pada penelitian ini berhasil dilakukan pembuatan material penyerap gelombang elektromagnetik komposit fasa NiFe 2 O 4 -NdFeO 3 dengan menggunakan Fe 2 O 3 , NiO, dan Nd 2 O 3 melalui reaksi padatan. Sampel komposit di milling dengan variasi waktu 10, 15, 20, dan 25 jam dan selanjutnya disinter pada suhu 1200 o C selama 3 jam. Identifikasi fasa dilakukan dengan X-ray Diffractometer (XRD) menunjukan bahwa komposit hanya terdiri dari fasa NiFe 2 O 4 dan NdFeO 3 . Ukuran kristalit fasa NiFe 2 O 4 berada pada kisaran 59-68 nm, sedangkan fasa NdFeO 3 pada kisaran 62-65 nm. Pengamatan morfologi permukaan dilakukan menggunakan Scanning Electron Microscope (SEM). Berdasarkan nilai parameter sifat magnetik yang dihasilkan menggunakan Vibrating Sample Magnetometer (VSM) seperti magnetisasi saturasi(Ms), magnetisasi remanen (Mr), dan koesivitas (Hc) sangat bergantung pada fraksi massa, ukuran kristalit, dan homogenitas fasa yang terbentuk.
{"title":"Pengaruh Waktu Milling Terhadap Mikrostruktur dan Sifat Magnetik Komposit NiFe2O4-NdFeO3 [Influence Of Milling Time on Microstructure and Magnetic Properties of NiFe2O4-NdFeO3 Composite]","authors":"A. Mulyawan, Y. Yunasfi, W. A. Adi","doi":"10.14203/metalurgi.v32i3.216","DOIUrl":"https://doi.org/10.14203/metalurgi.v32i3.216","url":null,"abstract":"The development of electromagnetic wave and microwave absorbing materials was important to overcome the electromagnetic wave interference in communication technology and in the development of radar materials for military purposes. In this study the composite which contained two different phase s of NiFe 2 O 4 -NdFeO 3 has successfully synthesized using Fe 2 O 3 , NiO, and Nd 2 O 3 as starting materials through solid state reaction method. The composites were made by varying milling times from 10, 15, 20, and 25 hour s then followed by sintering process at 1200 °C for 3 hours . Phase identification was performed using XRD ( x -ray d iffractometer) which revealed only NiFe 2 O 4 and NdFeO 3 phase s . The crystallite size of the NiFe 2 O 4 phase is in the range of 59-68 nm, and NdFeO 3 in the range of 62-65 nm. The agglomeration of particles was observed by using SEM ( s canning e lectron m icroscope). Referring to the characterization result of the magnetic properties by using VSM ( v ibrating s ample m agnetometer), it is known that the parameters of the magnetic properties such as m agnetization saturation (Ms), magnetization remanence (Mr), and c oercivity (Hc) are highly dependent on the mass fraction, crystallite size, and the homogenity of the phase composition. Abstrak Pengembangan bahan penyerap gelombang elektromagnetik dan gelombang mikro sangat penting dilakukan untuk mengatasi masalah interferensi gelombang elektromagnetik pada teknologi komunikasi serta pada material radar untuk tujuan militer. Pada penelitian ini berhasil dilakukan pembuatan material penyerap gelombang elektromagnetik komposit fasa NiFe 2 O 4 -NdFeO 3 dengan menggunakan Fe 2 O 3 , NiO, dan Nd 2 O 3 melalui reaksi padatan. Sampel komposit di milling dengan variasi waktu 10, 15, 20, dan 25 jam dan selanjutnya disinter pada suhu 1200 o C selama 3 jam. Identifikasi fasa dilakukan dengan X-ray Diffractometer (XRD) menunjukan bahwa komposit hanya terdiri dari fasa NiFe 2 O 4 dan NdFeO 3 . Ukuran kristalit fasa NiFe 2 O 4 berada pada kisaran 59-68 nm, sedangkan fasa NdFeO 3 pada kisaran 62-65 nm. Pengamatan morfologi permukaan dilakukan menggunakan Scanning Electron Microscope (SEM). Berdasarkan nilai parameter sifat magnetik yang dihasilkan menggunakan Vibrating Sample Magnetometer (VSM) seperti magnetisasi saturasi(Ms), magnetisasi remanen (Mr), dan koesivitas (Hc) sangat bergantung pada fraksi massa, ukuran kristalit, dan homogenitas fasa yang terbentuk.","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"32 1","pages":"105-114"},"PeriodicalIF":0.6,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46853799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-09-30DOI: 10.14203/METALURGI.V32I2.320
D. Aryanto, N. Husniya, T. Sudiro, E. Hastuti
{"title":"Perlakuan Panas Ganda pada Fabrikasi Film Tipis AZO Nanokristal dengan Teknik Spray : Studi XRD [Double Heat Treatments On The Fabrication Of Nanocrystalline Azo Thin Films By Spray Technique: XRD Studies]","authors":"D. Aryanto, N. Husniya, T. Sudiro, E. Hastuti","doi":"10.14203/METALURGI.V32I2.320","DOIUrl":"https://doi.org/10.14203/METALURGI.V32I2.320","url":null,"abstract":"","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"32 1","pages":"45-52"},"PeriodicalIF":0.6,"publicationDate":"2017-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48633545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-09-30DOI: 10.14203/METALURGI.V27I2.348
Siska Prifiharni, Denni Ahmad, Andini Juniarsih, Efendi Mabruri
{"title":"STRUKTURMIKRO, KEKERASAN, DAN KETAHANAN KOROSI BAJA TAHAN KARAT MARTENSITIK 13Cr3Mo3Ni HASIL QUENCH-TEMPER DENGAN VARIASI TEMPERATUR DAN WAKTU AUSTENISASI","authors":"Siska Prifiharni, Denni Ahmad, Andini Juniarsih, Efendi Mabruri","doi":"10.14203/METALURGI.V27I2.348","DOIUrl":"https://doi.org/10.14203/METALURGI.V27I2.348","url":null,"abstract":"","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"27 1","pages":"83-90"},"PeriodicalIF":0.6,"publicationDate":"2017-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47675125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-09-30DOI: 10.14203/METALURGI.V32I2.326
Siska Prifiharni, Denni Ahmad, Andini Juniarsih, Efendi Mabruri
Martensitic stainless steel type 410 have been extensively used for turbine blade in steam turbine system. Their properties can be improved in various ways, such as modification element and heat treatment. The modified stainless steel in this case is martensitic stainless steel 13Cr-3Mo-3Ni were hot forged then annealed. Afterwards, martensitic stainless steel 13Cr-3Mo-3Ni were prepared and heat treated. Martensitic stainless steel 13Cr-3Mo-3Ni were austenized at temperature 950, 1000, 1050, dan 1100 °C for 1 and 3 hour followed by quench in oil. After quenching, material were tempered at 650°C for 1 hour. Several examinations were carried out on the material such as of hardness test with rockwell C, metallographic using optical microscope, and corrosion test using CMS ( c orrosion m easurement s ystem). The results show that martensitic stainless steel 13Cr3Mo3Ni at austenitizing temperature of 950 °C for 1 hour and tempering at 650 °C for 1 hour has the lowest hardness value with hardness value was 33 . 5 HRC and the lowest corrosion rate 0 . 02 mpy, whereas at austenitizing temperature of 1100 °C for 3 hours and tempering at 650 °C for 1 hour has the highest hardness value with hardness value was 46 . 2 HRC and the highest corrosion rate 1 . 62 mpy. The microstructures formed are martensite, carbide, and ferrite delta phases. Increased hardness at austenitizing temperature 1100 °C is due to an increase in carbide content in the martensite phase. However, carbide precipitation formed during quenching process can decrease corrosion resistance as Cr and Mo levels decrease in carbides . Abstrak Baja tahan karat martensitik tipe 410 biasa digunakan untuk aplikasi sudu turbin pada steam turbine. Perilaku baja tahan karat jenis ini dapat diperbaiki dengan berbagai cara, salah satunya yaitu dengan cara memodifikasi unsur baja tahan karat tipe 410 tersebut dan perlakuan panas. Baja tahan karat yang telah dimodifikasi dilakukan proses hot forging kemudian dianil. Sampel kemudian dipreparasi dan dilakukan proses perlakuan panas. Proses perlakuan panas yang dilakukan yaitu austenitisasi pada variasi suhu 950, 1000, 1050, dan 1100⁰C selama 1 dan 3 jam dan didinginkan dengan menggunakan media oli. Sampel yang telah diaustenitiasi dilakukan proses temper pada suhu 650⁰C selama 1 jam. Sampel tersebut kemudian dilakukan uji kekerasan, strukturmikro, dan ketahanan korosi yang terjadi setelah melalui proses perlakuan panas. Hasil menunjukkan bahwa nilai kekerasan dan laju korosi yang paling rendah pada suhu austenitisasi 950⁰C selama 1 jam dan paling tinggi pada suhu austenitisasi 1100⁰C selama 3 jam. Hal ini dapat terjadi karena adanya perubahan struktur martensit yang menjadi lebih kasar pada suhu austenitisasi yang lebih tinggi.
{"title":"Strukturmikro, Kekerasan, dan Ketahanan Korosi Baja Tahan Karat Martensitik 13Cr3Mo3Ni Hasil Quench-Temper dengan Variasi Temperatur dan Waktu Austenisasi [Microstructure, Hardness, and Corrosion Resistant of Martensitic Stainless Steel 13Cr3Mo3Ni after Quench-Temper with Various Austenization Tempe","authors":"Siska Prifiharni, Denni Ahmad, Andini Juniarsih, Efendi Mabruri","doi":"10.14203/METALURGI.V32I2.326","DOIUrl":"https://doi.org/10.14203/METALURGI.V32I2.326","url":null,"abstract":"Martensitic stainless steel type 410 have been extensively used for turbine blade in steam turbine system. Their properties can be improved in various ways, such as modification element and heat treatment. The modified stainless steel in this case is martensitic stainless steel 13Cr-3Mo-3Ni were hot forged then annealed. Afterwards, martensitic stainless steel 13Cr-3Mo-3Ni were prepared and heat treated. Martensitic stainless steel 13Cr-3Mo-3Ni were austenized at temperature 950, 1000, 1050, dan 1100 °C for 1 and 3 hour followed by quench in oil. After quenching, material were tempered at 650°C for 1 hour. Several examinations were carried out on the material such as of hardness test with rockwell C, metallographic using optical microscope, and corrosion test using CMS ( c orrosion m easurement s ystem). The results show that martensitic stainless steel 13Cr3Mo3Ni at austenitizing temperature of 950 °C for 1 hour and tempering at 650 °C for 1 hour has the lowest hardness value with hardness value was 33 . 5 HRC and the lowest corrosion rate 0 . 02 mpy, whereas at austenitizing temperature of 1100 °C for 3 hours and tempering at 650 °C for 1 hour has the highest hardness value with hardness value was 46 . 2 HRC and the highest corrosion rate 1 . 62 mpy. The microstructures formed are martensite, carbide, and ferrite delta phases. Increased hardness at austenitizing temperature 1100 °C is due to an increase in carbide content in the martensite phase. However, carbide precipitation formed during quenching process can decrease corrosion resistance as Cr and Mo levels decrease in carbides . Abstrak Baja tahan karat martensitik tipe 410 biasa digunakan untuk aplikasi sudu turbin pada steam turbine. Perilaku baja tahan karat jenis ini dapat diperbaiki dengan berbagai cara, salah satunya yaitu dengan cara memodifikasi unsur baja tahan karat tipe 410 tersebut dan perlakuan panas. Baja tahan karat yang telah dimodifikasi dilakukan proses hot forging kemudian dianil. Sampel kemudian dipreparasi dan dilakukan proses perlakuan panas. Proses perlakuan panas yang dilakukan yaitu austenitisasi pada variasi suhu 950, 1000, 1050, dan 1100⁰C selama 1 dan 3 jam dan didinginkan dengan menggunakan media oli. Sampel yang telah diaustenitiasi dilakukan proses temper pada suhu 650⁰C selama 1 jam. Sampel tersebut kemudian dilakukan uji kekerasan, strukturmikro, dan ketahanan korosi yang terjadi setelah melalui proses perlakuan panas. Hasil menunjukkan bahwa nilai kekerasan dan laju korosi yang paling rendah pada suhu austenitisasi 950⁰C selama 1 jam dan paling tinggi pada suhu austenitisasi 1100⁰C selama 3 jam. Hal ini dapat terjadi karena adanya perubahan struktur martensit yang menjadi lebih kasar pada suhu austenitisasi yang lebih tinggi.","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"32 1","pages":"83-90"},"PeriodicalIF":0.6,"publicationDate":"2017-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42422599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-09-30DOI: 10.14203/metalurgi.v32i2.319
D. N. Adnyana
Light vehicle is a potentially useful and efficient mode of transportation to be utilized in supporting the coal mine operation. However, due to the harsh road condition at the mine site, many light vehicles presently used are frequently experiencing a number of incidents caused by loose wheel. The occurrence of this loose wheel is very much related with some broken or damaged wheel studs and/or nuts of the vehicle. Type of failure and factors that may have caused the damage of the wheel studs and/or nuts of the vehicles are discussed in this paper. The metallurgical assessment was conducted by preparing a number of specimens from the damaged and undamaged wheel studs and nuts of the vehicles. Various laboratory examinations were performed including macroscopic examination, chemical composition analysis, metallographic examination, hardness test and SEM (scanning electron microscopy) examination equipped with EDS (energy dispersive spectroscopy) analysis. In addition, torsion test was also conducted on several new studs and nuts to measure the relationship between the torque and angular displacement. Results of the metallurgical assessment obtained show that the damaged wheel studs have experienced fatigue crack or fracture that was caused by load cycling under unidirectional bending at a low nominal stress. Most of the fatigue cracks were originated from the common fatigue initiation sites at the thread root of the stud. There are four possible factors that may have contributed to the acceleration of fatigue failure on the wheel studs or nuts of the light vehicles, either singly or in combination, including improper use of the vehicle, improper material of the wheel stud, improper material of the wheel and/or incorrect installation of the stud and wheel joint. Abstrak Kendaraan ringan merupakan moda transportasi yang potensial dan efisien digunakan dalam mendukung operasi tambang batubara. Akan tetapi, karena kondisi jalan yang sangat buruk pada lokasi pertambangan, banyak kendaraan ringan yang saat ini digunakan sering mengalami kecelakaan akibat terjadi kelonggaran pada roda. Terjadinya kelonggaran pada roda tersebut sangat terkait dengan patahnya atau rusaknya baut dan/atau mur roda kendaraan tersebut. Dalam makalah ini dibahas jenis kerusakan dan faktor-faktor yang kemungkinan telah menyebabkan terjadinya kerusakan pada baut dan/atau mur roda kendaraan. Penelitian/pengujian metalurgi telah dilakukan dengan menggunakan sejumlah benda uji yang diambil dari baut dan mur roda kendaraan, baik yang telah rusak maupun yang tidak rusak. Berbagai pengujian laboratorium telah dilakukan meliputi: uji makro, analisa komposisi kimia, uji metalografi, uji kekerasan dan uji SEM (scanning electron microscopy) yang dilengkapi dengan analisis EDS (energy dispersive spectroscopy) . Disamping itu, uji torsi juga telah dilakukan pada beberapa baut dan mur yang baru untuk mengukur hubungan antara momen torsi dan sudut torsi. Hasil dari penelitian/pengujian metalu
轻型汽车是一种潜在的、有用的、高效的运输方式，可用于煤矿的辅助作业。然而，由于矿区道路条件恶劣，目前使用的许多轻型车辆经常发生车轮松动的事故。这种松动车轮的发生与车辆的一些车轮螺柱和/或螺母断裂或损坏有很大关系。本文讨论了车辆车轮螺柱和/或螺母损坏的类型和可能造成损坏的因素。通过从车辆的损坏和未损坏的车轮螺柱和螺母中制备一些样品，进行了冶金评估。进行了各种实验室检查，包括宏观检查，化学成分分析，金相检查，硬度测试和SEM(扫描电子显微镜)检查，并配有EDS(能量色散光谱)分析。此外，还对几种新的螺柱和螺母进行了扭转试验，测量了扭矩与角位移的关系。金相评价结果表明，在低标称应力下单向弯曲载荷循环引起的疲劳裂纹或断裂。大多数疲劳裂纹起源于螺柱螺纹根部的常见疲劳起裂部位。有四种可能的因素可能导致轻型车辆的车轮螺柱或螺母加速疲劳失效，无论是单独的还是组合的，包括车辆使用不当，车轮螺柱材料不当，车轮材料不当和/或螺柱和车轮接头安装不当。【摘要】肯达拉、林根、梅鲁帕坎、公路、公路、公路、公路、公路、公路、公路、公路、公路、公路、公路、公路、公路、公路、公路、公路、公路等。阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶，阿甘茶。Terjadinya kelonggaran padroda tersebut sangat terkait dengan patahnya atau rusaknya baut dan/atau mur roda kendaraan tersebut。Dalam makalah ini dibahas jenis kerusakan dan factor - factor for yang kemungkinan telah menyebabkan terjadinya kerusakan paada baut dan/atau mur roda kendaraan。Penelitian/ penguian metalurgi telah dilakukan dengan menggunakan sejumlah benduji yang diambil dari baut danmur roda kendaraan, baik yang telah rusak maupun yang tidak rusak。Berbagai实验室:uji makro, analisa komposisi kimia, uji金相学，uji kekerasan, uji SEM(扫描电子显微镜)，yang dilengkapi dengan分析EDS(能量色散光谱)。Disamping itu, uji torsi juga telah dilakukan paada beberapa baut danmur yang baru untuk mengukur hubungan antara力矩torsi dansudut torsi。企鹅金属学，企鹅金属学，企鹅金属学，企鹅金属学，企鹅金属学，企鹅金属学，企鹅金属学，企鹅金属学，企鹅金属学
{"title":"Kerusakan Fatik pada Baut dan Mur Roda Kendaraan Ringan untuk Operasi Tambang Batubara [Fatigue Failure of Wheel Studs and Nuts of Light Vehicles Used in Coal Mine Operation]","authors":"D. N. Adnyana","doi":"10.14203/metalurgi.v32i2.319","DOIUrl":"https://doi.org/10.14203/metalurgi.v32i2.319","url":null,"abstract":"Light vehicle is a potentially useful and efficient mode of transportation to be utilized in supporting the coal mine operation. However, due to the harsh road condition at the mine site, many light vehicles presently used are frequently experiencing a number of incidents caused by loose wheel. The occurrence of this loose wheel is very much related with some broken or damaged wheel studs and/or nuts of the vehicle. Type of failure and factors that may have caused the damage of the wheel studs and/or nuts of the vehicles are discussed in this paper. The metallurgical assessment was conducted by preparing a number of specimens from the damaged and undamaged wheel studs and nuts of the vehicles. Various laboratory examinations were performed including macroscopic examination, chemical composition analysis, metallographic examination, hardness test and SEM (scanning electron microscopy) examination equipped with EDS (energy dispersive spectroscopy) analysis. In addition, torsion test was also conducted on several new studs and nuts to measure the relationship between the torque and angular displacement. Results of the metallurgical assessment obtained show that the damaged wheel studs have experienced fatigue crack or fracture that was caused by load cycling under unidirectional bending at a low nominal stress. Most of the fatigue cracks were originated from the common fatigue initiation sites at the thread root of the stud. There are four possible factors that may have contributed to the acceleration of fatigue failure on the wheel studs or nuts of the light vehicles, either singly or in combination, including improper use of the vehicle, improper material of the wheel stud, improper material of the wheel and/or incorrect installation of the stud and wheel joint. Abstrak Kendaraan ringan merupakan moda transportasi yang potensial dan efisien digunakan dalam mendukung operasi tambang batubara. Akan tetapi, karena kondisi jalan yang sangat buruk pada lokasi pertambangan, banyak kendaraan ringan yang saat ini digunakan sering mengalami kecelakaan akibat terjadi kelonggaran pada roda. Terjadinya kelonggaran pada roda tersebut sangat terkait dengan patahnya atau rusaknya baut dan/atau mur roda kendaraan tersebut. Dalam makalah ini dibahas jenis kerusakan dan faktor-faktor yang kemungkinan telah menyebabkan terjadinya kerusakan pada baut dan/atau mur roda kendaraan. Penelitian/pengujian metalurgi telah dilakukan dengan menggunakan sejumlah benda uji yang diambil dari baut dan mur roda kendaraan, baik yang telah rusak maupun yang tidak rusak. Berbagai pengujian laboratorium telah dilakukan meliputi: uji makro, analisa komposisi kimia, uji metalografi, uji kekerasan dan uji SEM (scanning electron microscopy) yang dilengkapi dengan analisis EDS (energy dispersive spectroscopy) . Disamping itu, uji torsi juga telah dilakukan pada beberapa baut dan mur yang baru untuk mengukur hubungan antara momen torsi dan sudut torsi. Hasil dari penelitian/pengujian metalu","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"32 1","pages":"53-66"},"PeriodicalIF":0.6,"publicationDate":"2017-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45118150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-09-30DOI: 10.14203/METALURGI.V32I2.309
R. D. Desiati, E. Sugiarti, E. Junianto, E. Martides, Budi Prawara
Micro structure and micro hardness characterizations have been done on NiCoCrAl coating sample deposited on different substrate, i..e, carbon steel, nickel chrome and hastealloy. NiCoCrAlY coating was deposited by high velocity oxy fuel (HVOF) thermal spraying technique. Characterization and measurents were applied on all cross section samples. Micro structural analysis was characterized by optical microscope with 40x magnification. Moreover, micro hardness tester was utilized to measure the hardness of the sample with 300 gf for 13 second. The hardness data was measure by calculating the average of 3 position of hardness measurement on substrate before coating, after coating and NiCoCrAl coating layer. According to micro structural analysis, it reveald that the thickness of NiCoCrAlYcoating layer was about 370.76 m m, 92 m m, dan 29 on carbon steel, nickel chrome and hastealloy substrate, respectively. Surface morfology showed that the coated layer was not flat and porous structure or void on the coated layer. The porosity of the coated layer might effect the mechanical properties of the sample where high procentase of porosity might reduce the hardness of the sample. The hardness of NiCoCrAlY coating was about 349.95 , 315.60 and 311.30 HV for carbon steel, nickel chrome and hastealloy substrate, respectively. The distance from interface between coating layer and substrate might effect hardness measurement where closer to interface could decrease hardness value and it might caused by interdiffusion of coating elements thus effect to its mechanical properties. Abstrak Telah dilakukan karakterisasi strukturmikro dan kekerasan mikro pada lapisan NiCoCrAlY yang dideposisikan di atas substrat yang berbeda yaitu baja karbon, nikel krom dan hastealloy. Lapisan NiCoCrAlY dideposisikan menggunakan teknik penyemprotan HVOF ( high velocity oxy fuel ) . Proses karakterisasi dan pengukuran dilakukan pada seluruh lapisan dengan irisan melintang. Karakterisasi strukturmikro diamati dengan menggunakan mikroskop optik dengan perbesaran 40x. Selanjutnya untuk pengukuran kekerasan menggunakan kekerasan mikro dengan beban 300 gf selama 13 detik. Data pengujian kekerasan diperoleh dengan mengukur nilai rata-rata dari 3 posisi uji kekerasan pada masing-masing bagian substrat sebelum dilapisi, setelah dilapisi dan lapisan NiCoCrAlY. Berdasarkan hasil karakterisasi strukturmikro diketahui bahwa lapisan NiCoCrAlY berhasil terdeposisi dengan ketebalan 370,76 mm, 92 mm, dan 115,73 mm masing-masing di atas substrat baja karbon, nikel krom dan hastealloy. Morfologi permukaan lapisan menunjukkan bahwa lapisan yang terdeposisi tidak begitu rata dan masih tampak adanya pori atau lubang di area lapisan NiCoCrAlY yang terbentuk. Porositas dari lapisan sangat berpengaruh pada sifat mekanik, semakin tinggi persentase porositas lapisan maka kekerasan akan menurun. Nilai kekerasan lapisan NiCoCrAlY pada substrat baja karbon adalah sebesar 349,95 HV, nikel krom sebesar 315,60
{"title":"Pengaruh Substrat Terhadap Kekerasan Lapisan NiCoCrAlY Yang Terdeposisi Dengan Teknik HVOF[Effect of Different Substrate on Hardness Properties of NiCoCrAlY Coatings Deposited by HVOF Technique]","authors":"R. D. Desiati, E. Sugiarti, E. Junianto, E. Martides, Budi Prawara","doi":"10.14203/METALURGI.V32I2.309","DOIUrl":"https://doi.org/10.14203/METALURGI.V32I2.309","url":null,"abstract":"Micro structure and micro hardness characterizations have been done on NiCoCrAl coating sample deposited on different substrate, i..e, carbon steel, nickel chrome and hastealloy. NiCoCrAlY coating was deposited by high velocity oxy fuel (HVOF) thermal spraying technique. Characterization and measurents were applied on all cross section samples. Micro structural analysis was characterized by optical microscope with 40x magnification. Moreover, micro hardness tester was utilized to measure the hardness of the sample with 300 gf for 13 second. The hardness data was measure by calculating the average of 3 position of hardness measurement on substrate before coating, after coating and NiCoCrAl coating layer. According to micro structural analysis, it reveald that the thickness of NiCoCrAlYcoating layer was about 370.76 m m, 92 m m, dan 29 on carbon steel, nickel chrome and hastealloy substrate, respectively. Surface morfology showed that the coated layer was not flat and porous structure or void on the coated layer. The porosity of the coated layer might effect the mechanical properties of the sample where high procentase of porosity might reduce the hardness of the sample. The hardness of NiCoCrAlY coating was about 349.95 , 315.60 and 311.30 HV for carbon steel, nickel chrome and hastealloy substrate, respectively. The distance from interface between coating layer and substrate might effect hardness measurement where closer to interface could decrease hardness value and it might caused by interdiffusion of coating elements thus effect to its mechanical properties. Abstrak Telah dilakukan karakterisasi strukturmikro dan kekerasan mikro pada lapisan NiCoCrAlY yang dideposisikan di atas substrat yang berbeda yaitu baja karbon, nikel krom dan hastealloy. Lapisan NiCoCrAlY dideposisikan menggunakan teknik penyemprotan HVOF ( high velocity oxy fuel ) . Proses karakterisasi dan pengukuran dilakukan pada seluruh lapisan dengan irisan melintang. Karakterisasi strukturmikro diamati dengan menggunakan mikroskop optik dengan perbesaran 40x. Selanjutnya untuk pengukuran kekerasan menggunakan kekerasan mikro dengan beban 300 gf selama 13 detik. Data pengujian kekerasan diperoleh dengan mengukur nilai rata-rata dari 3 posisi uji kekerasan pada masing-masing bagian substrat sebelum dilapisi, setelah dilapisi dan lapisan NiCoCrAlY. Berdasarkan hasil karakterisasi strukturmikro diketahui bahwa lapisan NiCoCrAlY berhasil terdeposisi dengan ketebalan 370,76 mm, 92 mm, dan 115,73 mm masing-masing di atas substrat baja karbon, nikel krom dan hastealloy. Morfologi permukaan lapisan menunjukkan bahwa lapisan yang terdeposisi tidak begitu rata dan masih tampak adanya pori atau lubang di area lapisan NiCoCrAlY yang terbentuk. Porositas dari lapisan sangat berpengaruh pada sifat mekanik, semakin tinggi persentase porositas lapisan maka kekerasan akan menurun. Nilai kekerasan lapisan NiCoCrAlY pada substrat baja karbon adalah sebesar 349,95 HV, nikel krom sebesar 315,60","PeriodicalId":18462,"journal":{"name":"Metalurgija","volume":"32 1","pages":"91-96"},"PeriodicalIF":0.6,"publicationDate":"2017-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48230140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：