Pub Date : 2024-06-11DOI: 10.24425/afe.2024.149279
J.S. Zych
The paper presents the results of the analysis of cooling curves of cast iron with approximately eutectic composition rasterized at different rates of cooling and ingot crystallization. The test samples were in the form of rods with a diameter of 30,0.mm and a coagulation modulus M = 0.75 cm. They were cast in a sand mould made of furan mass placed on a chill in the form of a cast-iron plate, with which one of the front surfaces of the rod casting was in contact. In this way, a differentiated cooling rate along the rod was achieved. At selected distances from the chiller (5, 15, 25, 25 and 45 mm) thermocouple moulds were placed in the cavity to record the cooling curves used in thermal (AT) and derivation (ATD) analysis. The solidification time of the ingot in the part farthest from the chiller was about 200s, which corresponds to the solidification time in the test cup AT. An analysis of the recorded cooling curves was performed in order to determine the values of characteristic points on the AT curve (Tsol. Tliq, ΔTrecal., τclot, etc.). Relationships between cooling time and rate and characteristic points on AT and ATD curves were developed. For example, Tsol min changes in the range of 1115 - 1145 for the range of cast iron solidification times in the selected ingot zone from ~ 70 to ~ 200 s, which corresponds to the process speed from 0.0047 to 0.014 [1/s]. The work also includes an analysis of other characteristic points on the AT and ATD curves as functions of the solidification rate of cast iron of the same composition.
本文介绍了对近似共晶成分的铸铁在不同冷却速度和铸锭结晶情况下的冷却曲线的分析结果。测试样品为棒状，直径为 30.0 毫米，凝固模量 M = 0.75 厘米。它们被浇铸在呋喃砂模中，砂模放置在铸铁板状的冷却器上，棒铸件的一个前表面与铸铁板接触。通过这种方式，可以实现沿棒的不同冷却速度。在与冷却器的选定距离（5、15、25、25 和 45 毫米）处，在型腔中放置热电偶模具，以记录用于热分析（AT）和推导分析（ATD）的冷却曲线。在离冷却器最远的部分，钢锭的凝固时间约为 200 秒，与试验杯 AT 的凝固时间一致。对记录的冷却曲线进行了分析，以确定 AT 曲线上特征点的值 (Tsol. Tliq, ΔTrecal., τclot 等)。冷却时间和冷却速率与 AT 和 ATD 曲线上的特征点之间的关系已经形成。例如，在所选铸锭区的铸铁凝固时间范围从 ~ 70 到 ~ 200 s（相当于 0.0047 到 0.014 [1/s]的工艺速度）内，Tsol min 的变化范围为 1115 - 1145。工作还包括分析 AT 和 ATD 曲线上的其他特征点作为相同成分铸铁凝固速率的函数。
{"title":"Influence of the Rate of Cooling/Solidification on the Location of Characteristic Points on the AT and ADT Curves of Cast Iron","authors":"J.S. Zych","doi":"10.24425/afe.2024.149279","DOIUrl":"https://doi.org/10.24425/afe.2024.149279","url":null,"abstract":"The paper presents the results of the analysis of cooling curves of cast iron with approximately eutectic composition rasterized at different rates of cooling and ingot crystallization. The test samples were in the form of rods with a diameter of 30,0.mm and a coagulation modulus M = 0.75 cm. They were cast in a sand mould made of furan mass placed on a chill in the form of a cast-iron plate, with which one of the front surfaces of the rod casting was in contact. In this way, a differentiated cooling rate along the rod was achieved. At selected distances from the chiller (5, 15, 25, 25 and 45 mm) thermocouple moulds were placed in the cavity to record the cooling curves used in thermal (AT) and derivation (ATD) analysis. The solidification time of the ingot in the part farthest from the chiller was about 200s, which corresponds to the solidification time in the test cup AT. An analysis of the recorded cooling curves was performed in order to determine the values of characteristic points on the AT curve (Tsol. Tliq, ΔTrecal., τclot, etc.). Relationships between cooling time and rate and characteristic points on AT and ATD curves were developed. For example, Tsol min changes in the range of 1115 - 1145 for the range of cast iron solidification times in the selected ingot zone from ~ 70 to ~ 200 s, which corresponds to the process speed from 0.0047 to 0.014 [1/s]. The work also includes an analysis of other characteristic points on the AT and ATD curves as functions of the solidification rate of cast iron of the same composition.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141356778","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 : 2024-06-11DOI: 10.24425/afe.2024.149275
M. Skrzyński, R. Dańko, G. Dajczer
The publication presents a new shooting technique with reduced pressure in venting system for manufacturing foundry cores using inorganic sand mixture with Cordis binder. Traditional technologies for producing casting cores using blowing methods, despite their undeniable advantages, including the ability to produce cores in series, also come with some disadvantages. The primary drawbacks of the process involve uneven compaction structure of the cores, with denser areas primarily located under the blow holes, and under-shooting defects, which often occur in regions away from the blow hole or in increased core cross-sectional areas. In an effort to improve core quality, a concept was developed that involves incorporating a reduced pressure in the core box venting system to support the basic overpressure process. The solutions proposed in the publication with a vacuum method of filling the cavities of multi-chamber core boxes solve a number of technical problems occurring in conventional blowing technologies. It eliminates difficulties associated with evacuating the sand from the chamber to the shooting head and into technological cavity and increases the uniform distribution and initial degree of compacting of grains in the cavity. The additive role of this “underpressure” support is to enhance corebox venting by eliminating 'air cushions' in crevices and structural elements that obstruct the flow of evacuated air. The publication presents the results of studies on core manufacturing using blowing methods conducted in three variants: classic overpressure, utilizing the core box filling phenomenon by reducing pressure, and an integrated approach combining both these methods.
{"title":"The Technique of Inorganic Core Sand Shooting with Reduced Pressure in Venting System","authors":"M. Skrzyński, R. Dańko, G. Dajczer","doi":"10.24425/afe.2024.149275","DOIUrl":"https://doi.org/10.24425/afe.2024.149275","url":null,"abstract":"The publication presents a new shooting technique with reduced pressure in venting system for manufacturing foundry cores using inorganic sand mixture with Cordis binder. Traditional technologies for producing casting cores using blowing methods, despite their undeniable advantages, including the ability to produce cores in series, also come with some disadvantages. The primary drawbacks of the process involve uneven compaction structure of the cores, with denser areas primarily located under the blow holes, and under-shooting defects, which often occur in regions away from the blow hole or in increased core cross-sectional areas. In an effort to improve core quality, a concept was developed that involves incorporating a reduced pressure in the core box venting system to support the basic overpressure process. The solutions proposed in the publication with a vacuum method of filling the cavities of multi-chamber core boxes solve a number of technical problems occurring in conventional blowing technologies. It eliminates difficulties associated with evacuating the sand from the chamber to the shooting head and into technological cavity and increases the uniform distribution and initial degree of compacting of grains in the cavity. The additive role of this “underpressure” support is to enhance corebox venting by eliminating 'air cushions' in crevices and structural elements that obstruct the flow of evacuated air. The publication presents the results of studies on core manufacturing using blowing methods conducted in three variants: classic overpressure, utilizing the core box filling phenomenon by reducing pressure, and an integrated approach combining both these methods.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141358404","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 : 2024-06-11DOI: 10.24425/afe.2024.149280
J. Marosz, S. Sobula
A method for fabrication of a composite layer on the surface of a steel casting using coating containing TiC substrates was presented. The reaction of the synthesis of the ceramic phase was based on the SHS method (Self-propagating High-temperature Synthesis) and was triggered by the heat of molten steel. High hardness titanium carbide ceramic phases were obtained, which strengthened the base material improving its performance properties presented in this article. Microstructural examinations carried out by light microscopy (LM) on the in-situ produced composite layers showed that the layers were the products of reaction of the TiC synthesis – the phenomenon called “fragmentation” by the authors of study. The examinations carried out by scanning electron microscopy (SEM) have revealed the presence of spheroidal precipitated and free of impurities. The presence of titanium carbide was twofold increase in hardness in the area of the composite layer as compared to the base alloy which was carbon cast steel.
{"title":"Analysis of Fragmentation Phenomenon of Composite Layers of Fe-TiC Type Obtained “in situ” in Steel Casting","authors":"J. Marosz, S. Sobula","doi":"10.24425/afe.2024.149280","DOIUrl":"https://doi.org/10.24425/afe.2024.149280","url":null,"abstract":"A method for fabrication of a composite layer on the surface of a steel casting using coating containing TiC substrates was presented. The reaction of the synthesis of the ceramic phase was based on the SHS method (Self-propagating High-temperature Synthesis) and was triggered by the heat of molten steel. High hardness titanium carbide ceramic phases were obtained, which strengthened the base material improving its performance properties presented in this article. Microstructural examinations carried out by light microscopy (LM) on the in-situ produced composite layers showed that the layers were the products of reaction of the TiC synthesis – the phenomenon called “fragmentation” by the authors of study. The examinations carried out by scanning electron microscopy (SEM) have revealed the presence of spheroidal precipitated and free of impurities. The presence of titanium carbide was twofold increase in hardness in the area of the composite layer as compared to the base alloy which was carbon cast steel.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141357753","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 : 2024-06-11DOI: 10.24425/afe.2024.149277
Jialiu Lei, Yongjun Fu, Li Xiong
As an alloying element in steel, manganese can considerably enhance the mechanical properties of structural steel. However, the Mn volatilisation loss in vacuum melting is severe because of the high saturated vapour pressure, resulting in an unstable Mn yield and Mn content fluctuation. Therefore, a systematic study of the volatilisation behaviour of Mn in vacuum melting is required to obtain a suitable Mn control process to achieve precise control of Mn composition, thereby providing a theoretical basis for industrial melting of high-Mn steel. In order to explore the Mn volatilization behavior, the volatilization thermodynamics and volatilisation rate of Mn, as well as the influence factors are discussed in this study. The results shows that Mn is extremely volatilised into the vapour phase under vacuum, the equilibrium partial pressure is closely related to Mn content and temperature. With an increase in the Mn content, a higher C content has a more obvious inhibitory effect on the equilibrium partial pressure of Mn. The maximum theoretical volatilisation rate of Mn shows a linear upward trend with an increase in Mn content. However, a higher C content has a more obvious effect on the reduction of the maximum theoretical volatilisation rate with the increase of Mn content. This study provides an improved understanding of Mn volatilisation behaviour as well as a theoretical foundation for consistent Mn yield control during the vacuum melting process of high-Mn steel.
作为钢中的一种合金元素，锰能大大提高结构钢的机械性能。然而，由于饱和蒸汽压较高，真空熔炼中的锰挥发损失严重，导致锰收得率和锰含量波动不稳定。因此，需要对真空熔炼中锰的挥发行为进行系统研究，以获得合适的锰控制流程，实现对锰成分的精确控制，从而为高锰钢的工业熔炼提供理论依据。为了探索锰的挥发行为，本研究讨论了锰的挥发热力学和挥发速率以及影响因素。结果表明，锰在真空条件下极易挥发到气相中，其平衡分压与锰含量和温度密切相关。随着锰含量的增加，较高的 C 含量对锰的平衡分压有更明显的抑制作用。随着锰含量的增加，锰的最大理论挥发率呈线性上升趋势。然而，随着锰含量的增加，较高的 C 含量对最大理论挥发率的降低有更明显的影响。这项研究加深了对锰挥发行为的理解，并为在高锰钢真空熔炼过程中实现一致的锰屈服控制奠定了理论基础。
{"title":"Study on Mn Volatilization Behavior During Vacuum Melting of High-manganese Steel","authors":"Jialiu Lei, Yongjun Fu, Li Xiong","doi":"10.24425/afe.2024.149277","DOIUrl":"https://doi.org/10.24425/afe.2024.149277","url":null,"abstract":"As an alloying element in steel, manganese can considerably enhance the mechanical properties of structural steel. However, the Mn volatilisation loss in vacuum melting is severe because of the high saturated vapour pressure, resulting in an unstable Mn yield and Mn content fluctuation. Therefore, a systematic study of the volatilisation behaviour of Mn in vacuum melting is required to obtain a suitable Mn control process to achieve precise control of Mn composition, thereby providing a theoretical basis for industrial melting of high-Mn steel. In order to explore the Mn volatilization behavior, the volatilization thermodynamics and volatilisation rate of Mn, as well as the influence factors are discussed in this study. The results shows that Mn is extremely volatilised into the vapour phase under vacuum, the equilibrium partial pressure is closely related to Mn content and temperature. With an increase in the Mn content, a higher C content has a more obvious inhibitory effect on the equilibrium partial pressure of Mn. The maximum theoretical volatilisation rate of Mn shows a linear upward trend with an increase in Mn content. However, a higher C content has a more obvious effect on the reduction of the maximum theoretical volatilisation rate with the increase of Mn content. This study provides an improved understanding of Mn volatilisation behaviour as well as a theoretical foundation for consistent Mn yield control during the vacuum melting process of high-Mn steel.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141360153","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 : 2024-06-11DOI: 10.24425/afe.2024.149281
V.V. Ramalingam, K.V. Shankar, B. Shankar, R. Abhinandan, A. Dineshkumar, P.A. Adhithyan, K. Velusamy, A. Kapilan, N. Sudheer
This research investigates the microstructural evolution and mechanical properties of LM25 (Al-Si-Mg) alloy and Cr-modified LM25-Cr (Al-Si-Mg-Cr) alloy. Microstructural analysis reveals distinctive ε-Si phase morphologies, with Cr addition refining dendritic structures and reducing secondary dendrite arm spacing in the as-cast condition. Cr modification results in smaller-sized grains and a modified ε-Si phase, enhancing nucleation sites and reducing ε-Si size. Microhardness studies demonstrate significant increases in hardness for both alloys after solutionising and aging treatments. Cr-enriched alloy exhibits superior hardness due to solid solution strengthening, and prolonged aging further influences ε-Si particle size and distribution. The concurrent rise in microhardness, attributed to refined dendritic structures and unique ε-Si morphology, underscores the crucial role of Cr modification in tailoring the mechanical properties of aluminium alloys for specific applications.
{"title":"Impact of Aging Time on the Metallurgical Properties and Hardness Characteristics of an Al-Si-Mg-Cr Hypoeutectic Alloy Intended for Automotive Applications","authors":"V.V. Ramalingam, K.V. Shankar, B. Shankar, R. Abhinandan, A. Dineshkumar, P.A. Adhithyan, K. Velusamy, A. Kapilan, N. Sudheer","doi":"10.24425/afe.2024.149281","DOIUrl":"https://doi.org/10.24425/afe.2024.149281","url":null,"abstract":"This research investigates the microstructural evolution and mechanical properties of LM25 (Al-Si-Mg) alloy and Cr-modified LM25-Cr (Al-Si-Mg-Cr) alloy. Microstructural analysis reveals distinctive ε-Si phase morphologies, with Cr addition refining dendritic structures and reducing secondary dendrite arm spacing in the as-cast condition. Cr modification results in smaller-sized grains and a modified ε-Si phase, enhancing nucleation sites and reducing ε-Si size. Microhardness studies demonstrate significant increases in hardness for both alloys after solutionising and aging treatments. Cr-enriched alloy exhibits superior hardness due to solid solution strengthening, and prolonged aging further influences ε-Si particle size and distribution. The concurrent rise in microhardness, attributed to refined dendritic structures and unique ε-Si morphology, underscores the crucial role of Cr modification in tailoring the mechanical properties of aluminium alloys for specific applications.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141357143","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 : 2024-03-26DOI: 10.24425/afe.2024.149264
Chengmin Wang, Anatoly Politov, Xiuhui Wang, Jinlong Yang
In view of the increasing scarcity of bauxite resources in China, the high energy consumption and high pollution of electrolytic aluminum, and the requirements for energy conservation and environmental protection, aluminum recycling and high-value utilization of its derivatives have evolved into a crucial development requirement for the aluminum industry in the future. As an important part of the development of recycled aluminum resources, the high-value application of scrap aluminum cans has always been a hot research topic in various recycled aluminum processing enterprises and scientific research units. The traditional regeneration system of waste cans includes a series of complex technological processes such as pretreatment, paint removal, smelting system and casting system, which is difficult to control in the middle of the process. Most of the recycled scrap aluminum cans are cast and downgraded for later use, except for a part of them used as alloy materials for new cans. In this paper, combined with the research on the preparation of metal aluminum alkoxide, combined with recrystallization heat conduction to further study the effective dissolution or adsorption how to remove impurity elements to obtain high-purity aluminum alcohol salt mechanism research, and thermal effect of alcohols with different carbon chains on the synthesis of high-purity aluminum alkoxide was further investigated. Moreover, the changes in morphology and pore size distribution of hydrolyzed alumina precursor materials under different hydrothermal temperature conditions were discussed by means of the alkoxide hydrolysis-sol-gel process. Eventually, the aluminum alkoxide was obtained by the reaction of waste cans with isopropanol and heavy crystal thermal conductivity, and the high-purity aluminum alkoxide was purified by vacuum distillation. Under the hydrothermal condition of 160°C, the high-purity alumina material with a purity of 99.99% and an original crystal size of 200nm was prepared.
{"title":"Study on Preparation Technology and Heat Conduction Mechanism of High-Purity & Ultra-Fine Alumina Powder from Scrap Aluminum Cans","authors":"Chengmin Wang, Anatoly Politov, Xiuhui Wang, Jinlong Yang","doi":"10.24425/afe.2024.149264","DOIUrl":"https://doi.org/10.24425/afe.2024.149264","url":null,"abstract":"In view of the increasing scarcity of bauxite resources in China, the high energy consumption and high pollution of electrolytic aluminum, and the requirements for energy conservation and environmental protection, aluminum recycling and high-value utilization of its derivatives have evolved into a crucial development requirement for the aluminum industry in the future. As an important part of the development of recycled aluminum resources, the high-value application of scrap aluminum cans has always been a hot research topic in various recycled aluminum processing enterprises and scientific research units. The traditional regeneration system of waste cans includes a series of complex technological processes such as pretreatment, paint removal, smelting system and casting system, which is difficult to control in the middle of the process. Most of the recycled scrap aluminum cans are cast and downgraded for later use, except for a part of them used as alloy materials for new cans. In this paper, combined with the research on the preparation of metal aluminum alkoxide, combined with recrystallization heat conduction to further study the effective dissolution or adsorption how to remove impurity elements to obtain high-purity aluminum alcohol salt mechanism research, and thermal effect of alcohols with different carbon chains on the synthesis of high-purity aluminum alkoxide was further investigated. Moreover, the changes in morphology and pore size distribution of hydrolyzed alumina precursor materials under different hydrothermal temperature conditions were discussed by means of the alkoxide hydrolysis-sol-gel process. Eventually, the aluminum alkoxide was obtained by the reaction of waste cans with isopropanol and heavy crystal thermal conductivity, and the high-purity aluminum alkoxide was purified by vacuum distillation. Under the hydrothermal condition of 160°C, the high-purity alumina material with a purity of 99.99% and an original crystal size of 200nm was prepared.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140378169","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 : 2024-01-04DOI: 10.24425/afe.2024.149250
Kardo Rajagukguk, S. Suyitno, H. Saptoadi, I. Kusumaningtyas, B. Arifvianto, M. Mahardika
An as-cast aluminum billet with a diameter of 100 mm has been successfully prepared from aluminum scrap by using direct chill (DC) casting method. This study aims to investigate the microstructure and mechanical properties of such as-cast billets. Four locations along a cross-section of the as-cast billet radius were evaluated. The results show that the structures of the as-cast billet are a thin layer of coarse columnar grains at the solidified shell, feathery grains at the half radius of the billet, and coarse equiaxed grains at the billet center. The grain size tends to decrease from the center to the surface of the as-cast billet. The ultimate tensile strength (UTS) and the hardness values obtained from this research slightly increase from the center to the surface of the as-cast billet. The distribution of Mg, Fe, and Si elements over the cross-section of the as-cast billet is inhomogeneous. The segregation analysis shows that Si has negative segregation towards the surface, positive segregation at the middle, and negative segregation at the center of the as-cast billet. On the other hand, the Mg element is distributed uniformly in small quantities in the cross-section of the as-cast billet.
{"title":"Remelting of Aluminum Scrap Into Billets Using Direct Chill Casting","authors":"Kardo Rajagukguk, S. Suyitno, H. Saptoadi, I. Kusumaningtyas, B. Arifvianto, M. Mahardika","doi":"10.24425/afe.2024.149250","DOIUrl":"https://doi.org/10.24425/afe.2024.149250","url":null,"abstract":"An as-cast aluminum billet with a diameter of 100 mm has been successfully prepared from aluminum scrap by using direct chill (DC) casting method. This study aims to investigate the microstructure and mechanical properties of such as-cast billets. Four locations along a cross-section of the as-cast billet radius were evaluated. The results show that the structures of the as-cast billet are a thin layer of coarse columnar grains at the solidified shell, feathery grains at the half radius of the billet, and coarse equiaxed grains at the billet center. The grain size tends to decrease from the center to the surface of the as-cast billet. The ultimate tensile strength (UTS) and the hardness values obtained from this research slightly increase from the center to the surface of the as-cast billet. The distribution of Mg, Fe, and Si elements over the cross-section of the as-cast billet is inhomogeneous. The segregation analysis shows that Si has negative segregation towards the surface, positive segregation at the middle, and negative segregation at the center of the as-cast billet. On the other hand, the Mg element is distributed uniformly in small quantities in the cross-section of the as-cast billet.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140513888","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 : 2023-12-28DOI: 10.24425/afe.2023.146690
M. Mróz, S. Olszewska, P. Rąb
This paper presents the possibility of improving the scratch resistance of the AZ91 magnesium alloy by applying a WCCoCr coating using the Air Plasma Spraying (APS) method. The coating thickness ranged from 140 to 160 m. Microstructural studies of the AZ91 magnesium alloy were performed. The chemical composition of the WCCoCr powder was investigated. The quality of the bond at the substrate–coating interface was assessed and a microanalysis of the chemical composition of the coating was conducted. The scratch resistance of the AZ91 alloy and the WCCoCr coating was determined. The scratch resistance of the WCCoCr powder-based coating is much higher than the AZ91 alloy, as confirmed by scratch geometry measurements. The scratch width in the coating was almost three times smaller compared to the scratch in the substrate. Observations of the substrate–coating interface in the scratch area indicate no discontinuities. The absence of microcracks and delamination at the transition of the scratch from the substrate to the coating indicates good adhesion. On the basis of the study, it was found that there was great potential to use the WCCoCr powder coating to improve the abrasion resistance of castings made from the AZ91 alloy.
{"title":"Evaluation of the Possibility to Improve the Scratch Resistance of the AZ91 Alloy by Applying a Coating","authors":"M. Mróz, S. Olszewska, P. Rąb","doi":"10.24425/afe.2023.146690","DOIUrl":"https://doi.org/10.24425/afe.2023.146690","url":null,"abstract":"This paper presents the possibility of improving the scratch resistance of the AZ91 magnesium alloy by applying a WCCoCr coating using the Air Plasma Spraying (APS) method. The coating thickness ranged from 140 to 160 m. Microstructural studies of the AZ91 magnesium alloy were performed. The chemical composition of the WCCoCr powder was investigated. The quality of the bond at the substrate–coating interface was assessed and a microanalysis of the chemical composition of the coating was conducted. The scratch resistance of the AZ91 alloy and the WCCoCr coating was determined. The scratch resistance of the WCCoCr powder-based coating is much higher than the AZ91 alloy, as confirmed by scratch geometry measurements. The scratch width in the coating was almost three times smaller compared to the scratch in the substrate. Observations of the substrate–coating interface in the scratch area indicate no discontinuities. The absence of microcracks and delamination at the transition of the scratch from the substrate to the coating indicates good adhesion. On the basis of the study, it was found that there was great potential to use the WCCoCr powder coating to improve the abrasion resistance of castings made from the AZ91 alloy.","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139149326","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 : 2023-12-28DOI: 10.24425/afe.2023.148961
G. Tęcza
Cast martensitic alloy steel is used for the production of parts and components of machines operating under conditions of abrasive wear. One of the most popular grades is cast steel GX70CrMnSiNiMo2 steel, which is used in many industries, but primarily in the mining and material processing sectors for rings and balls operating in the grinding sets of coal mills. To improve the abrasion resistance of cast alloy tool steel, primary titanium carbides were produced in the metallurgical process by increasing the carbon content to 1.78 wt.% and adding 5.00 wt.% of titanium to test castings. After alloy solidification, the result was the formation of a microstructure consisting of a martensitic matrix with areas of residual austenite and primary titanium carbides evenly distributed in this matrix. The measured as-cast hardness of the samples was 660HV and it increased to as much as 800HV after heat treatment. The abrasion resistance of the sample hardened in a 15% polymer solution increased at least three times compared to the reference sample after quenching and
{"title":"Changes in the Microstructure and Abrasion Resistance of Tool Cast Steel after the Formation of Titanium Carbides in the Alloy Matrix","authors":"G. Tęcza","doi":"10.24425/afe.2023.148961","DOIUrl":"https://doi.org/10.24425/afe.2023.148961","url":null,"abstract":"Cast martensitic alloy steel is used for the production of parts and components of machines operating under conditions of abrasive wear. One of the most popular grades is cast steel GX70CrMnSiNiMo2 steel, which is used in many industries, but primarily in the mining and material processing sectors for rings and balls operating in the grinding sets of coal mills. To improve the abrasion resistance of cast alloy tool steel, primary titanium carbides were produced in the metallurgical process by increasing the carbon content to 1.78 wt.% and adding 5.00 wt.% of titanium to test castings. After alloy solidification, the result was the formation of a microstructure consisting of a martensitic matrix with areas of residual austenite and primary titanium carbides evenly distributed in this matrix. The measured as-cast hardness of the samples was 660HV and it increased to as much as 800HV after heat treatment. The abrasion resistance of the sample hardened in a 15% polymer solution increased at least three times compared to the reference sample after quenching and","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139149973","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 : 2023-12-28DOI: 10.24425/afe.2023.148960
K. Braszczyńska-malik
In this paper, an experimental Mg-Al-RE-type magnesium alloy, named AEZ951, is presented. The chemical composition of the investigated alloy was ca. 9 wt% Al, 5 wt% RE (rare earth elements), 0.7 wt% Zn and 3 wt% Mn. The experimental material was gravity cast into a cold steel mould. Microstructure analyses were carried out by light microscopy, along with X-ray phase analysis and scanning electron microscopy with an energy-dispersive X-ray spectrometer (SEM + EDX). Detailed investigations disclosed the presence of primary dendrites of an (Mg) solid solution and Al 11 RE 3 , and Al 10 RE 2 Mn 7 intermetallic compounds in the alloy microstructure. The volume fraction of the Al 11 RE 3 phase and + eutectic was also presented. The hardness, impact strength, tensile strength as well as the yield strength of the alloy were examined in tests at room temperature. The examined experimental Mg-Al-RE-type magnesium alloy exhibited higher mechanical properties than the commercial AZ91 alloy (cast in the same conditions).
本文介绍了一种名为 AEZ951 的实验性 Mg-Al-RE 型镁合金。所研究合金的化学成分约为 9 wt% Al、5 wt% RE（稀土元素）、0.7 wt% Zn 和 3 wt% Mn。实验材料被重力浇铸到冷钢模中。通过光学显微镜、X 射线相分析和扫描电子显微镜与能量色散 X 射线光谱仪（SEM + EDX）进行了微观结构分析。详细研究表明，合金微观结构中存在 (Mg) 固溶体的原生枝晶以及 Al 11 RE 3、 和 Al 10 RE 2 Mn 7 金属间化合物。此外，还介绍了 Al 11 RE 3 相和 + 共晶的体积分数。合金的硬度、冲击强度、拉伸强度和屈服强度在室温下的测试中进行了检验。与商用 AZ91 合金（在相同条件下铸造）相比，实验中的 Mg-Al-RE 型镁合金具有更高的机械性能。
{"title":"Microstructure and Properties of Experimental Mg-9Al-5RE-1Zn-Mn Magnesium Alloy","authors":"K. Braszczyńska-malik","doi":"10.24425/afe.2023.148960","DOIUrl":"https://doi.org/10.24425/afe.2023.148960","url":null,"abstract":"In this paper, an experimental Mg-Al-RE-type magnesium alloy, named AEZ951, is presented. The chemical composition of the investigated alloy was ca. 9 wt% Al, 5 wt% RE (rare earth elements), 0.7 wt% Zn and 3 wt% Mn. The experimental material was gravity cast into a cold steel mould. Microstructure analyses were carried out by light microscopy, along with X-ray phase analysis and scanning electron microscopy with an energy-dispersive X-ray spectrometer (SEM + EDX). Detailed investigations disclosed the presence of primary dendrites of an (Mg) solid solution and Al 11 RE 3 , and Al 10 RE 2 Mn 7 intermetallic compounds in the alloy microstructure. The volume fraction of the Al 11 RE 3 phase and + eutectic was also presented. The hardness, impact strength, tensile strength as well as the yield strength of the alloy were examined in tests at room temperature. The examined experimental Mg-Al-RE-type magnesium alloy exhibited higher mechanical properties than the commercial AZ91 alloy (cast in the same conditions).","PeriodicalId":8301,"journal":{"name":"Archives of Foundry Engineering","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139152653","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：