Amirthaiah Amala Mithin Minther Singh, Panimayam Arul Franco, Joseph Selvi Binoj, Amirthaiah Arul Shemin
The automated boat’s deckhouse is made of deforested wood and glass fiber, harming producers, fishermen, and marine life. In context, researchers are attempting to make composites from waste and replace synthetic materials with natural composites. In the present work, a Carbon/Mg/Si/polyester hybrid composite is developed as a potential replacement for wood in marine deckhouse construction. Impact, tensile, flexural, Rockwell and Brinell hardness were tested using ASTM standards, as well as weight absorption in fresh and seawater. Scanning electron microscopy (SEM), microanalysis (EDAX), Fourier-transform infrared spectroscopy (FTIR) and Raman Spectroscopy techniques were used to identify microstructure, elements, and functional groups. Thermogravimetric analysis and differential scanning calorimetry (DSC) are used to determine the thermal stability and heat intake/rejection of the hybrid composite. Novel hybrid composites with Mg-Si fillers improve the mechanical strength, adhesion, corrosion resistance, and deckhouse life span in marine environments.
{"title":"Mechanical, morphological and water intake behavior of Mg-Si integrated carbon hybrid composite for marine deckhouse","authors":"Amirthaiah Amala Mithin Minther Singh, Panimayam Arul Franco, Joseph Selvi Binoj, Amirthaiah Arul Shemin","doi":"10.3989/revmetalm.246","DOIUrl":"https://doi.org/10.3989/revmetalm.246","url":null,"abstract":"The automated boat’s deckhouse is made of deforested wood and glass fiber, harming producers, fishermen, and marine life. In context, researchers are attempting to make composites from waste and replace synthetic materials with natural composites. In the present work, a Carbon/Mg/Si/polyester hybrid composite is developed as a potential replacement for wood in marine deckhouse construction. Impact, tensile, flexural, Rockwell and Brinell hardness were tested using ASTM standards, as well as weight absorption in fresh and seawater. Scanning electron microscopy (SEM), microanalysis (EDAX), Fourier-transform infrared spectroscopy (FTIR) and Raman Spectroscopy techniques were used to identify microstructure, elements, and functional groups. Thermogravimetric analysis and differential scanning calorimetry (DSC) are used to determine the thermal stability and heat intake/rejection of the hybrid composite. Novel hybrid composites with Mg-Si fillers improve the mechanical strength, adhesion, corrosion resistance, and deckhouse life span in marine environments.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"45 26","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139451893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mathusoothana Perumal Ezhilan, L. Emmanual, S. Alagarsamy, M. Meignanamoorthy
Aluminium matrix composite (AMC) materials play an important role in the field of automobile and aerospace industries due to their excellent properties. In this research, aluminium alloy (AA7075) was reinforced with alumina (Al2O3) particles to improve their hardness and tribological behaviour of the base alloy. Four composites were prepared by varying the content (4, 8 and 12 wt.%) of Al2O3 particles through the stir casting technique. The surface morphology of the proposed composites ensured the uniform distribution of Al2O3 particles into the matrix alloy. The hardness of the composite was measured using a Brinell hardness tester and the maximum value of hardness was found in the AA7075 - 8 wt.% Al2O3 composite. Hence, a tribological investigation was carried out on this AA7075 - 8 wt.% Al2O3 composite. Load (P), sliding speed (V) and sliding velocity (D) were taken as the wear parameters for conducting the experiments. A Technique for Order Preference by Similarity to Ideal Preferred Solution (TOPSIS) approach has been applied to find out the optimal conditions of parameters to obtain the lowest wear rate (WR) and the co-efficient of friction (COF). The results showed that the lowest WR and COF was obtained at ‘P’ of 15 N, ‘V’ of 1 m•s-1 and ‘D’ of 1000 m•s-1. ANOVA results revealed that ‘P’ is the factor with the most significant contribution (38.36%), followed by ‘D’ (28.32%). The worn surface morphology of the confirmation experiment specimen was investigated by SEM and the wear mechanism was reported.
{"title":"Investigations on microstructure, hardness and tribological behaviour of AA7075-Al2O3 composites synthesized via stir casting route","authors":"Mathusoothana Perumal Ezhilan, L. Emmanual, S. Alagarsamy, M. Meignanamoorthy","doi":"10.3989/revmetalm.253","DOIUrl":"https://doi.org/10.3989/revmetalm.253","url":null,"abstract":"Aluminium matrix composite (AMC) materials play an important role in the field of automobile and aerospace industries due to their excellent properties. In this research, aluminium alloy (AA7075) was reinforced with alumina (Al2O3) particles to improve their hardness and tribological behaviour of the base alloy. Four composites were prepared by varying the content (4, 8 and 12 wt.%) of Al2O3 particles through the stir casting technique. The surface morphology of the proposed composites ensured the uniform distribution of Al2O3 particles into the matrix alloy. The hardness of the composite was measured using a Brinell hardness tester and the maximum value of hardness was found in the AA7075 - 8 wt.% Al2O3 composite. Hence, a tribological investigation was carried out on this AA7075 - 8 wt.% Al2O3 composite. Load (P), sliding speed (V) and sliding velocity (D) were taken as the wear parameters for conducting the experiments. A Technique for Order Preference by Similarity to Ideal Preferred Solution (TOPSIS) approach has been applied to find out the optimal conditions of parameters to obtain the lowest wear rate (WR) and the co-efficient of friction (COF). The results showed that the lowest WR and COF was obtained at ‘P’ of 15 N, ‘V’ of 1 m•s-1 and ‘D’ of 1000 m•s-1. ANOVA results revealed that ‘P’ is the factor with the most significant contribution (38.36%), followed by ‘D’ (28.32%). The worn surface morphology of the confirmation experiment specimen was investigated by SEM and the wear mechanism was reported.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"135 42","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139387603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study is concerned with the characterization of iron nuggets obtained from the reduction of an iron oxide concentrate in a microwave oven using a biomass-based reducing agent. In the experiments, the concentrate of iron ore consisting of hematite and magnetite minerals supplied from Elazig region and containing 67.29% Fe after enrichment, and as a reducing agent, tea plant wastes containing 94.68% C and 0.03% S after carbonization was used. Carbon required for the reduction of iron oxides to iron was stoichiometrically added to the concentrate with a grain size of -45 µm after its basicity ratio was adjusted. The composite pellets produced after the addition of reducing agent and flux (CaO) were subjected to reduction in a household microwave oven at different times. After the process, optimum (Fe3O4+Fe2O3)/C=1/4, basicity ratio (CaO+MgO)/(SiO2+Al2O3) =1.2 results were obtained. It was seen that the metallic part contained 96.6% Fe, 2.4% C after being separated from the slag and that the metallic phase was separated from the slag very easily. As a result of the microstructure investigations, it was found that the product obtained had similar properties to white cast iron properties.
本研究涉及使用生物质还原剂在微波炉中还原氧化铁精矿所得到的铁块的特征。在实验中，使用了来自埃拉泽格地区的由赤铁矿和磁铁矿矿物组成的铁矿精矿，富集后含铁 67.29%；作为还原剂，使用了碳化后含 C 94.68% 和 S 0.03% 的茶树废料。将铁氧化物还原成铁所需的碳按比例添加到粒度为 -45 µm 的浓缩物中，然后调整其碱度比。添加还原剂和助熔剂（氧化钙）后产生的复合球团在家用微波炉中进行不同时间的还原。经过这一过程后，得到了最佳（Fe3O4+Fe2O3）/C=1/4，碱度比（CaO+MgO）/（SiO2+Al2O3）=1.2 的结果。结果表明，从炉渣中分离出来的金属部分含有 96.6% 的 Fe 和 2.4% 的 C，而且金属相很容易从炉渣中分离出来。微观结构研究结果表明，获得的产品具有与白口铸铁相似的特性。
{"title":"Characterization of iron nugget produced from iron ore concentrate in a microwave oven using a biomass-based reductant","authors":"M. Boyrazlı, Elif Aranci Öztürk, Yunus Emre Benkli, Canan Aksu Canbay","doi":"10.3989/revmetalm.250","DOIUrl":"https://doi.org/10.3989/revmetalm.250","url":null,"abstract":"This study is concerned with the characterization of iron nuggets obtained from the reduction of an iron oxide concentrate in a microwave oven using a biomass-based reducing agent. In the experiments, the concentrate of iron ore consisting of hematite and magnetite minerals supplied from Elazig region and containing 67.29% Fe after enrichment, and as a reducing agent, tea plant wastes containing 94.68% C and 0.03% S after carbonization was used. Carbon required for the reduction of iron oxides to iron was stoichiometrically added to the concentrate with a grain size of -45 µm after its basicity ratio was adjusted. The composite pellets produced after the addition of reducing agent and flux (CaO) were subjected to reduction in a household microwave oven at different times. After the process, optimum (Fe3O4+Fe2O3)/C=1/4, basicity ratio (CaO+MgO)/(SiO2+Al2O3) =1.2 results were obtained. It was seen that the metallic part contained 96.6% Fe, 2.4% C after being separated from the slag and that the metallic phase was separated from the slag very easily. As a result of the microstructure investigations, it was found that the product obtained had similar properties to white cast iron properties.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"37 20","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139452061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nodular cast irons are used in many industrial applications such as machine frames and body, rollers and engine blocks due to their higher strengths and ductility with good machinability comparable to grey cast irons. In this study, the outer surface of nodular cast irons (GGG-60) was coated with WC/Co using electro spark deposition (ESD). The aim of the study is to improve both the surface quality and wear behaviour with the coatings formed on the surface of the plastic deformation rollers, whose wear resistance decreases over the time due to high stress working conditions. Heat treatment at 950 ºC for 2 h was applied to the GGG60 specimen rollers and half of the rollers were uncoated and the other half was coated with WC-Co electrodes. The wear behaviour of the heat treated and coated surfaces was measured by ball-on-disc wear method using Al2O3 ball bearing with a diameter of 6 mm for a sliding distance of 250 m at a sliding rate of 6.5 m·s-1 under a dry condition, and using a load of 40 N. WC/Co coatings were successfully applied to rollers. In the SEM/EDS images, the presence of W, Fe, C, Co and Al elements in the coated part of the rollers and Fe, C and Al elements in the uncoated region were detected. It was concluded that Coating and heat treatment increased the wear resistance by nearly 5 times and decreased the friction coefficient by 2.13 times.
{"title":"Wear performance of GGG60 ductile iron rollers coated with WC-Co by electro spark deposition","authors":"M. Buğday, Mehmet Karalı, Ş. Talaş","doi":"10.3989/revmetalm.249","DOIUrl":"https://doi.org/10.3989/revmetalm.249","url":null,"abstract":"Nodular cast irons are used in many industrial applications such as machine frames and body, rollers and engine blocks due to their higher strengths and ductility with good machinability comparable to grey cast irons. In this study, the outer surface of nodular cast irons (GGG-60) was coated with WC/Co using electro spark deposition (ESD). The aim of the study is to improve both the surface quality and wear behaviour with the coatings formed on the surface of the plastic deformation rollers, whose wear resistance decreases over the time due to high stress working conditions. Heat treatment at 950 ºC for 2 h was applied to the GGG60 specimen rollers and half of the rollers were uncoated and the other half was coated with WC-Co electrodes. The wear behaviour of the heat treated and coated surfaces was measured by ball-on-disc wear method using Al2O3 ball bearing with a diameter of 6 mm for a sliding distance of 250 m at a sliding rate of 6.5 m·s-1 under a dry condition, and using a load of 40 N. WC/Co coatings were successfully applied to rollers. In the SEM/EDS images, the presence of W, Fe, C, Co and Al elements in the coated part of the rollers and Fe, C and Al elements in the uncoated region were detected. It was concluded that Coating and heat treatment increased the wear resistance by nearly 5 times and decreased the friction coefficient by 2.13 times.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"79 10","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139388190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Prabu Rajendran, Velmurugan Duraisamy, Ashok Raj Rajendran, Raja Velur Loganathan
The need to optimize the process parameters in Electrical Discharge Machining (EDM) for aged AA7075 Metal Matrix Composites (AAMMCs) is evident as it impacts various aspects such as mechanical properties, tool wear, surface finish, integrity, precision, accuracy, process stability, process consistency, and cost-effectiveness. In this study, aluminium alloy AA7075 was chosen as the matrix material because of the need to enhance its mechanical properties. Titanium Carbide (TiC) was chosen as the reinforcing material owing to its superior mechanical properties. Therefore, TiC holds the capability to improve the mechanical attributes of AA7075. The selection of the stir cast method for the manufacturing of AA7075/TiC (0, 4, 8, 12, and 16 wt.%) was based on its ease of fabrication, ability to achieve a uniform distribution of reinforcements, reduced susceptibility to oxidation and porosity, and improved control over the microstructure. This AA7075/12wt.%TiC MMC underwent an aging process at 520 °C for 180 min and was subsequently cooled within the furnace environment. The density of the aged and non-aged AA7075/TiC-based composites was determined through a density test using the Archimedes’ principle. Microhardness testing was conducted on the non-aged and aged AA7075-based MMCs employing a Vickers microhardness tester. Tensile strength and compressive strength of the aged and non-aged AA7075-based MMCs were determined by the usage of a universal testing machine (UTM) and a compression testing machine (CTM). The optimal combination of the manufactured AA7075/TiC MMCs was determined based on their mechanical properties. The most effective combination was identified as AA7075/12wt.%TiC MMC due to its superior values in hardness, tensile strength, compressive strength, and density compared to other combinations. The aging process aimed to enhance the mechanical properties without the need for additional reinforcements. EDAX and X-ray Diffraction Analysis (XRD) tests were employed to determine the weight percentage of the matrix and reinforcements and to identify the formation of precipitates in the AA7075/12wt.%TiC composites. The SEM equipment was utilized to verify the uniform distribution of titanium carbide in the matrix material AA7075. Optimization of EDM process parameters for aged AA7075/12wt.%TiC composite was carried out using Taguchi design-based Grey Relational Analysis (GRA). The selected input parameters for the optimization included the chromium concentration (g×l-1), current (amps) and pulse-on time (µs). The response parameters chosen for optimization were surface roughness (SR) and tool wear rate (TWR). The sequence of influencing EDM input parameters is chromium concentration, pulse on time and current. The optimized EDM process parameters were 8 g×l-1 chromium concentration, 5 amps current and 240 µs pulse on time and the corresponding response were 0.198 TWR and 1.56 SR.
{"title":"Optimization on the electrical discharge machining (EDM) process parameters of aged AA7075/TiC metal matrix composites","authors":"Prabu Rajendran, Velmurugan Duraisamy, Ashok Raj Rajendran, Raja Velur Loganathan","doi":"10.3989/revmetalm.245","DOIUrl":"https://doi.org/10.3989/revmetalm.245","url":null,"abstract":"The need to optimize the process parameters in Electrical Discharge Machining (EDM) for aged AA7075 Metal Matrix Composites (AAMMCs) is evident as it impacts various aspects such as mechanical properties, tool wear, surface finish, integrity, precision, accuracy, process stability, process consistency, and cost-effectiveness. In this study, aluminium alloy AA7075 was chosen as the matrix material because of the need to enhance its mechanical properties. Titanium Carbide (TiC) was chosen as the reinforcing material owing to its superior mechanical properties. Therefore, TiC holds the capability to improve the mechanical attributes of AA7075. The selection of the stir cast method for the manufacturing of AA7075/TiC (0, 4, 8, 12, and 16 wt.%) was based on its ease of fabrication, ability to achieve a uniform distribution of reinforcements, reduced susceptibility to oxidation and porosity, and improved control over the microstructure. This AA7075/12wt.%TiC MMC underwent an aging process at 520 °C for 180 min and was subsequently cooled within the furnace environment. The density of the aged and non-aged AA7075/TiC-based composites was determined through a density test using the Archimedes’ principle. Microhardness testing was conducted on the non-aged and aged AA7075-based MMCs employing a Vickers microhardness tester. Tensile strength and compressive strength of the aged and non-aged AA7075-based MMCs were determined by the usage of a universal testing machine (UTM) and a compression testing machine (CTM). The optimal combination of the manufactured AA7075/TiC MMCs was determined based on their mechanical properties. The most effective combination was identified as AA7075/12wt.%TiC MMC due to its superior values in hardness, tensile strength, compressive strength, and density compared to other combinations. The aging process aimed to enhance the mechanical properties without the need for additional reinforcements. EDAX and X-ray Diffraction Analysis (XRD) tests were employed to determine the weight percentage of the matrix and reinforcements and to identify the formation of precipitates in the AA7075/12wt.%TiC composites. The SEM equipment was utilized to verify the uniform distribution of titanium carbide in the matrix material AA7075. Optimization of EDM process parameters for aged AA7075/12wt.%TiC composite was carried out using Taguchi design-based Grey Relational Analysis (GRA). The selected input parameters for the optimization included the chromium concentration (g×l-1), current (amps) and pulse-on time (µs). The response parameters chosen for optimization were surface roughness (SR) and tool wear rate (TWR). The sequence of influencing EDM input parameters is chromium concentration, pulse on time and current. The optimized EDM process parameters were 8 g×l-1 chromium concentration, 5 amps current and 240 µs pulse on time and the corresponding response were 0.198 TWR and 1.56 SR.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"128 31","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139387553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study evaluates the performance of a user-defined combined hardening modeling method for advanced high-strength steels (AHSS) under monotonic and reversal loading conditions. The plastic behavior of TWIP980 and TRIP980 AHSS sheet metals is investigated using a cyclic plasticity modeling approach. The model incorporates an isotropic von Mises yield criterion and a single-term Chaboche nonlinear kinematic hardening rule. Monotonic and reversal loading stress-strain curves are predicted and compared with experimental results. The model accurately captured the Bauschinger effect for both materials, but it needs help to effectively model the permanent softening behavior observed in TWIP980 steel. Overall, the proposed modeling method agrees well with experimental results for monotonic loading and accurately represents the Bauschinger effect and transient behavior during reversal loading. However, better improvements are needed to capture the permanent softening behavior of TWIP980 steel.
{"title":"Characterizing the mechanical deformation response of AHSS steels: A comparative study of cyclic plasticity models under monotonic and reversal loading","authors":"Toros Arda Akşen, E. Esener, M. Firat","doi":"10.3989/revmetalm.251","DOIUrl":"https://doi.org/10.3989/revmetalm.251","url":null,"abstract":"This study evaluates the performance of a user-defined combined hardening modeling method for advanced high-strength steels (AHSS) under monotonic and reversal loading conditions. The plastic behavior of TWIP980 and TRIP980 AHSS sheet metals is investigated using a cyclic plasticity modeling approach. The model incorporates an isotropic von Mises yield criterion and a single-term Chaboche nonlinear kinematic hardening rule. Monotonic and reversal loading stress-strain curves are predicted and compared with experimental results. The model accurately captured the Bauschinger effect for both materials, but it needs help to effectively model the permanent softening behavior observed in TWIP980 steel. Overall, the proposed modeling method agrees well with experimental results for monotonic loading and accurately represents the Bauschinger effect and transient behavior during reversal loading. However, better improvements are needed to capture the permanent softening behavior of TWIP980 steel.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"21 3","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139388521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nickel-based Hastelloy C-2000 is widely used in the aerospace, chemical, and medicinal sectors. Investigating the potential efficacy of the spin arc welding process on Hastelloy C-2000 was the main focus of this study. In spin arc welding the centrifugal force has been obtained in the fusion zone, thus the weldbead quality increases. Weld current, rotating speed, and spin diameter are all separate parameters used in the welding procedure. The microstructural investigation was carried out using optical microscopy, X-Ray Diffraction (XRD), and field emission scanning electron microscopy (FESEM). The mechanical characteristics of the welded specimens were examined closely. Spin Arc Welding ultimate tensile strength (UTS), hardness value (HV), and impact experiments were compared to those of the Multi-pass Pulsed Current Gas Tungsten Arc welding method (MPCGTAW). In 27 tests, increasing the current and rotating speed resulted in greater penetration depth and weld height. The width of the weld was found to be a little high, with a spinning diameter of 2 mm. In comparison, samples 5 and 15 were found to have better hardness, tensile strength, and toughness, especially with suitable welding parameters such as current (120 I and 140 I), speed (1800 rpm), and spin diameter (2 mm and 3 mm). A microstructural study showed no grain segregation, contributing to the material’s increased hardness and tensile strength. The novel findings of the present study suggest that spin arc welding might be superior for various Hastelloy C-2000 connections that might have great applications in industries.
{"title":"Study on mechanical and micro structural properties of spin arc welding in Hastelloy C-2000","authors":"Ilavarasan Karthic Subramaniyan, Poosari Kumaravel Srividhya, Jothi Kesavan","doi":"10.3989/revmetalm.252","DOIUrl":"https://doi.org/10.3989/revmetalm.252","url":null,"abstract":"Nickel-based Hastelloy C-2000 is widely used in the aerospace, chemical, and medicinal sectors. Investigating the potential efficacy of the spin arc welding process on Hastelloy C-2000 was the main focus of this study. In spin arc welding the centrifugal force has been obtained in the fusion zone, thus the weldbead quality increases. Weld current, rotating speed, and spin diameter are all separate parameters used in the welding procedure. The microstructural investigation was carried out using optical microscopy, X-Ray Diffraction (XRD), and field emission scanning electron microscopy (FESEM). The mechanical characteristics of the welded specimens were examined closely. Spin Arc Welding ultimate tensile strength (UTS), hardness value (HV), and impact experiments were compared to those of the Multi-pass Pulsed Current Gas Tungsten Arc welding method (MPCGTAW). In 27 tests, increasing the current and rotating speed resulted in greater penetration depth and weld height. The width of the weld was found to be a little high, with a spinning diameter of 2 mm. In comparison, samples 5 and 15 were found to have better hardness, tensile strength, and toughness, especially with suitable welding parameters such as current (120 I and 140 I), speed (1800 rpm), and spin diameter (2 mm and 3 mm). A microstructural study showed no grain segregation, contributing to the material’s increased hardness and tensile strength. The novel findings of the present study suggest that spin arc welding might be superior for various Hastelloy C-2000 connections that might have great applications in industries.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"45 12","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139389065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Because the growth behaviors of fatigue cracks are crucial for the safe assessment of structural components, the crack propagation behaviors of coarse-grained copper (CG Cu) subjected to cyclic torsion combined with different axial static stresses were studied. The crack bifurcation behavior is related to the strain amplitude applied. When the strain amplitude is lower, both the type and the magnitude of axial stress have no significant effect on the direction in which the primary crack branches, which is mainly determined by the position of the maximum normal plane. However, when the strain amplitude is higher, the bifurcated crack deviates visibly from the maximum normal plane, which can be attributed to the high degree of plastic deformation and microcracks caused by slip bands along longitudinal direction.
{"title":"Crack bifurcation behavior of coarse-grained copper under cyclic torsion combined with axial static loading","authors":"Jin Yue Liu, Rong Hua Li, Ji Chen","doi":"10.3989/revmetalm.248","DOIUrl":"https://doi.org/10.3989/revmetalm.248","url":null,"abstract":"Because the growth behaviors of fatigue cracks are crucial for the safe assessment of structural components, the crack propagation behaviors of coarse-grained copper (CG Cu) subjected to cyclic torsion combined with different axial static stresses were studied. The crack bifurcation behavior is related to the strain amplitude applied. When the strain amplitude is lower, both the type and the magnitude of axial stress have no significant effect on the direction in which the primary crack branches, which is mainly determined by the position of the maximum normal plane. However, when the strain amplitude is higher, the bifurcated crack deviates visibly from the maximum normal plane, which can be attributed to the high degree of plastic deformation and microcracks caused by slip bands along longitudinal direction.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"8 12","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138956777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cyanide is used in several industries but is widely used for gold extraction due to its ability to complex and stabilize gold ions. The waste generated from this process is of great volume because of low ore grades that requires more processing areas. Also, it is highly toxic due to cyanide being a contaminant of animal life and the environment. The mining sector can recycle the effluents generated in their processes, however, this can affect the gold extraction and treatment methods. There are legal laws that define cyanide levels in effluents for disposal in water bodies. Methodologies for reaching these levels include oxidation degradation processes, physical-chemical, biological processes, adsorption, photocatalysis, among others. In this present review, the use of cyanide in gold mining and some of these methodologies for removing cyanide in effluents generated by gold processing are evaluated.
{"title":"Impacts of cyanide in gold mining and cyanide removal methodologies in liquid waste from gold processing","authors":"Juliana Freitas, Daniela Horta","doi":"10.3989/revmetalm.247","DOIUrl":"https://doi.org/10.3989/revmetalm.247","url":null,"abstract":"Cyanide is used in several industries but is widely used for gold extraction due to its ability to complex and stabilize gold ions. The waste generated from this process is of great volume because of low ore grades that requires more processing areas. Also, it is highly toxic due to cyanide being a contaminant of animal life and the environment. The mining sector can recycle the effluents generated in their processes, however, this can affect the gold extraction and treatment methods. There are legal laws that define cyanide levels in effluents for disposal in water bodies. Methodologies for reaching these levels include oxidation degradation processes, physical-chemical, biological processes, adsorption, photocatalysis, among others. In this present review, the use of cyanide in gold mining and some of these methodologies for removing cyanide in effluents generated by gold processing are evaluated.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"127 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138953630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muhammad Samiuddin, Jinglong Li, Mudassir Farooq, J. Xiong
The study mainly focused on examining nanomechanical properties and corrosion behavior of the weld interface formed by diffusion welding of CoCrNi MEA and SUS 304 stainless steel. Three different bonding temperatures (i.e. 950 °C, 1000 °C, and 1050 °C) were utilized in producing diffusion welded joints. The influence of bonding temperatures on nanomechanical properties of the weld interface was characterized through Nanoindentation tests under various loads (i.e. 20 mN to 100 mN). Additionally, electrochemical properties of the weld interface were also examined using a 0.5 M HCl solution. Results clinched that with the increase of bonding temperature significant suppression in carbide formation occurred along with the weld interface. This instigated a reduction in nano hardness and elastic moduli which resulted in maximum elastic recovery along with the weld interface. The indentation size effect was also evident below 40 mN load after which nano hardness became stable while elastic moduli remained impervious to the change of indentation load. Furthermore, based upon electrochemical properties (i.e. Icorr, Ep, and Rp) samples welded at 1000 °C bonding temperature offered excellent corrosion resistance under 0.5M HCl environment.
该研究主要侧重于检测钴铬镍 MEA 和 SUS 304 不锈钢通过扩散焊接形成的焊接界面的纳米力学性能和腐蚀行为。在生产扩散焊接接头时采用了三种不同的焊接温度（即 950 ℃、1000 ℃ 和 1050 ℃）。通过在不同载荷（即 20 mN 至 100 mN）下进行纳米压痕测试，确定了接合温度对焊接界面纳米力学性能的影响。此外，还使用 0.5 M HCl 溶液检测了焊接界面的电化学特性。结果表明，随着焊接温度的升高，焊接界面的碳化物形成明显减少。这导致纳米硬度和弹性模量的降低，从而使焊接界面的弹性恢复最大。压痕大小效应在 40 毫牛顿载荷以下也很明显，之后纳米硬度变得稳定，而弹性模量则不受压痕载荷变化的影响。此外，根据电化学特性（即 Icorr、Ep 和 Rp），在 1000 °C 焊接温度下焊接的样品在 0.5M HCl 环境下具有优异的耐腐蚀性。
{"title":"Evaluation of nano mechanical properties and corrosion behavior of diffusion welded CoCrNi medium-entropy alloy (MEA) and SUS 304 stainless steel joints","authors":"Muhammad Samiuddin, Jinglong Li, Mudassir Farooq, J. Xiong","doi":"10.3989/revmetalm.244","DOIUrl":"https://doi.org/10.3989/revmetalm.244","url":null,"abstract":"The study mainly focused on examining nanomechanical properties and corrosion behavior of the weld interface formed by diffusion welding of CoCrNi MEA and SUS 304 stainless steel. Three different bonding temperatures (i.e. 950 °C, 1000 °C, and 1050 °C) were utilized in producing diffusion welded joints. The influence of bonding temperatures on nanomechanical properties of the weld interface was characterized through Nanoindentation tests under various loads (i.e. 20 mN to 100 mN). Additionally, electrochemical properties of the weld interface were also examined using a 0.5 M HCl solution. Results clinched that with the increase of bonding temperature significant suppression in carbide formation occurred along with the weld interface. This instigated a reduction in nano hardness and elastic moduli which resulted in maximum elastic recovery along with the weld interface. The indentation size effect was also evident below 40 mN load after which nano hardness became stable while elastic moduli remained impervious to the change of indentation load. Furthermore, based upon electrochemical properties (i.e. Icorr, Ep, and Rp) samples welded at 1000 °C bonding temperature offered excellent corrosion resistance under 0.5M HCl environment.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"18 4","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138974798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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