Javier Cárcel Carrasco, F. Salas Vicente, Aurora Martínez Corral, Manuel Pascual Guillamón
This paper analyzes the corrosion resistance and the mechanical and microstructural properties of a welded joint of ductile cast iron using AISI316L stainless steel as filler material and three different heat treatments: preheating at 250 and 450 ºC and a post-weld annealing treatment. The results show the presence of ledeburite at the interface between the weld bead and the heat affected zone and at the root pass, along with a loss of strength and ductility when the welding coupons are preheated. An annealing does not eliminate the presence of ledeburite and leads to a massive precipitation of chromium carbides at the areas of the weld bead where dilution is higher. Corrosion rate was lower for the annealed coupon, but in that case, the corrosion of the weld bead increases due to the precipitation of chromium carbides.
{"title":"Weldability of ductile cast iron using AISI-316L stainless steel ER rod","authors":"Javier Cárcel Carrasco, F. Salas Vicente, Aurora Martínez Corral, Manuel Pascual Guillamón","doi":"10.3989/revmetalm.224","DOIUrl":"https://doi.org/10.3989/revmetalm.224","url":null,"abstract":"This paper analyzes the corrosion resistance and the mechanical and microstructural properties of a welded joint of ductile cast iron using AISI316L stainless steel as filler material and three different heat treatments: preheating at 250 and 450 ºC and a post-weld annealing treatment. The results show the presence of ledeburite at the interface between the weld bead and the heat affected zone and at the root pass, along with a loss of strength and ductility when the welding coupons are preheated. An annealing does not eliminate the presence of ledeburite and leads to a massive precipitation of chromium carbides at the areas of the weld bead where dilution is higher. Corrosion rate was lower for the annealed coupon, but in that case, the corrosion of the weld bead increases due to the precipitation of chromium carbides.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44084012","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}
The performance of anionic exchange resin Dowex 1x8 in the removal of arsenic(V) from aqueous solutions was investigated. Batch experimentation was carried out under different variables, including, the stirring speed applied on the system, the pH of the aqueous solution, resin dosage and temperature. Due to the characteristic speciation of arsenic(V) in aqueous phases, the removal of this element from the solution is negligible at highly acidic or alkaline pH values, but it is possible at the aqueous pH range of 4-9, thus, both HAsO42- and H2AsO4- species are loaded onto the resin. At the above pH range, arsenic(V) uptake is exothermic. Different models are fitted to the experimental values in order to gain knowledge about this ion exchange system: rate law, kinetics and solute loading onto the resin. This loading is compared against the yielded using non-functionalized multiwalled carbon nanotubes. The elution step is investigated using acidic solutions (HCl medium) as eluent, from the eluted solutions, arsenic(V) can be efficiently stabilized as ferric or calcium arsenates.
{"title":"The removal of toxic metals from liquid effluents by ion exchange resins. Part XVII: Arsenic(V)/H+/Dowex 1x8","authors":"Francisco José Alguacil, E. Escudero","doi":"10.3989/revmetalm.221","DOIUrl":"https://doi.org/10.3989/revmetalm.221","url":null,"abstract":"The performance of anionic exchange resin Dowex 1x8 in the removal of arsenic(V) from aqueous solutions was investigated. Batch experimentation was carried out under different variables, including, the stirring speed applied on the system, the pH of the aqueous solution, resin dosage and temperature. Due to the characteristic speciation of arsenic(V) in aqueous phases, the removal of this element from the solution is negligible at highly acidic or alkaline pH values, but it is possible at the aqueous pH range of 4-9, thus, both HAsO42- and H2AsO4- species are loaded onto the resin. At the above pH range, arsenic(V) uptake is exothermic. Different models are fitted to the experimental values in order to gain knowledge about this ion exchange system: rate law, kinetics and solute loading onto the resin. This loading is compared against the yielded using non-functionalized multiwalled carbon nanotubes. The elution step is investigated using acidic solutions (HCl medium) as eluent, from the eluted solutions, arsenic(V) can be efficiently stabilized as ferric or calcium arsenates.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48200485","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}
In this research, the effect of the shielded metal arc welding (SMAW) process heat input upon the microstructure and development of the heat-affected zone in the dissimilar joint of API 5L X80/DS5 2205 steels was investigated by recording the thermal cycles with thermocouple implantation in the perpendicular direction of the weld line. The filler metal used (electrode) is DSS 2209. The microstructure of the base and weld metals and their interfaces at different heat inputs were investigated using the scanning electron microscopy/energy-dispersive spectroscopy analysis technique (SEM/EDS) and optical microscopy (OM). The results indicated that the interface between the base metals and the weld metal has excellent consistency and that there is no evidence of cracks at different heat inputs. By increasing the heat input, it was determined that the amount of secondary austenite in the weld metal and heat-affected zone of 2205 steel had been increased. There occurred an epitaxial growth at the interface of 2209/2205, and there were a fine transition zone and Type II boundaries at the interface of 2209/ API 5L X80. The areas containing coarse, fine, and partially fine grains were detected in the heat-affected zone of the X80 steel. The thermal cycle results determined that the temperature peak in the areas away from the fusion line had increased by increasing the heat input and that the heat-affected zone of the two base metals, particularly the X80 steel, had been extended further.
通过记录垂直焊缝方向热电偶注入的热循环，研究了保护金属电弧焊(SMAW)工艺热输入对API 5L X80/DS5 2205钢异种接头显微组织和热影响区发展的影响。所使用的填充金属(电极)是dss2209。采用扫描电镜/能谱分析技术(SEM/EDS)和光学显微镜(OM)研究了不同热输入下母材和焊缝金属及其界面的显微组织。结果表明，母材与焊缝金属之间的界面具有良好的一致性，在不同的热输入下均未出现裂纹。通过增加热输入，2205钢焊缝金属和热影响区的二次奥氏体数量增加。2209/2205的界面处出现了外延生长，2209/ API 5L X80的界面处出现了细小的过渡区和II型边界。在X80钢的热影响区检测到含有粗、细和部分细晶粒的区域。热循环结果表明，随着热输入的增加，远离熔合线区域的温度峰值有所增加，两种贱金属，特别是X80钢的热影响区进一步扩大。
{"title":"The effect of heat input on microstructure and HAZ expansion in dissimilar joints between API5L X80 / DSS 2205 steels using thermal cycles","authors":"Seyed Meisam Zahraei, R. Dehmolaei, A. Ashrafi","doi":"10.3989/revmetalm.222","DOIUrl":"https://doi.org/10.3989/revmetalm.222","url":null,"abstract":"In this research, the effect of the shielded metal arc welding (SMAW) process heat input upon the microstructure and development of the heat-affected zone in the dissimilar joint of API 5L X80/DS5 2205 steels was investigated by recording the thermal cycles with thermocouple implantation in the perpendicular direction of the weld line. The filler metal used (electrode) is DSS 2209. The microstructure of the base and weld metals and their interfaces at different heat inputs were investigated using the scanning electron microscopy/energy-dispersive spectroscopy analysis technique (SEM/EDS) and optical microscopy (OM). The results indicated that the interface between the base metals and the weld metal has excellent consistency and that there is no evidence of cracks at different heat inputs. By increasing the heat input, it was determined that the amount of secondary austenite in the weld metal and heat-affected zone of 2205 steel had been increased. There occurred an epitaxial growth at the interface of 2209/2205, and there were a fine transition zone and Type II boundaries at the interface of 2209/ API 5L X80. The areas containing coarse, fine, and partially fine grains were detected in the heat-affected zone of the X80 steel. The thermal cycle results determined that the temperature peak in the areas away from the fusion line had increased by increasing the heat input and that the heat-affected zone of the two base metals, particularly the X80 steel, had been extended further.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48929562","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}
C. Cruz-Gónzalez, B. Vargas-Arista, I. León-Méndez, I. Guzmán-Flores
The effectivity of the forming limit diagrams in manufacturing wheelbarrow by deep-drawing is shown because of the high material scrap rate which reduces productivity. Several chemical, mechanical testing and microstructural analysis were performed to examine sheet quality and their impact on these diagrams. Chemical analysis revealed that Steel 1 and Steel 3 sheets fulfilled the specification without assuring adequate forming process. However, the higher titanium content of Steel 2 improved its formability since it promoted the formation of fine precipitates, thus refining the grain size. This steel had the highest ASTM grain size number G (9.11), which is the lowest average grain size (13 µm) compared to the other steels, which had G values in the range 8.7 to 9.11. Moreover, Steel 2 sheets had the greatest plastic strain ratio (rm = 1.80), the highest strain-hardening exponent (n = 0.250), the lowest anisotropy ∆r = 0.31), yielding better results in deep-drawing strain distribution, the highest forming limit strain (28%) and the highest uniform elongation zone, favoring that failure sites did not occur.
{"title":"On the application of the forming limit diagrams for quality control of blanks for wheelbarrow of ASTM A1008 carbon steel","authors":"C. Cruz-Gónzalez, B. Vargas-Arista, I. León-Méndez, I. Guzmán-Flores","doi":"10.3989/revmetalm.218","DOIUrl":"https://doi.org/10.3989/revmetalm.218","url":null,"abstract":"The effectivity of the forming limit diagrams in manufacturing wheelbarrow by deep-drawing is shown because of the high material scrap rate which reduces productivity. Several chemical, mechanical testing and microstructural analysis were performed to examine sheet quality and their impact on these diagrams. Chemical analysis revealed that Steel 1 and Steel 3 sheets fulfilled the specification without assuring adequate forming process. However, the higher titanium content of Steel 2 improved its formability since it promoted the formation of fine precipitates, thus refining the grain size. This steel had the highest ASTM grain size number G (9.11), which is the lowest average grain size (13 µm) compared to the other steels, which had G values in the range 8.7 to 9.11. Moreover, Steel 2 sheets had the greatest plastic strain ratio (rm = 1.80), the highest strain-hardening exponent (n = 0.250), the lowest anisotropy ∆r = 0.31), yielding better results in deep-drawing strain distribution, the highest forming limit strain (28%) and the highest uniform elongation zone, favoring that failure sites did not occur.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43402287","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}
The Differential Speed Rolling (DSR) process is a severe plastic deformation method used in the production of microstructured materials with both high deformation and superior mechanical properties. This study has focused on determining the springback behavior and formability of the materials obtained by using the DSR method after the V bending process. Rolling processes were carried out at 4 different rolling speed ratios (1.0, 1.33, 1.66, and 2.0), 25% thickness reduction ratio, and 2 different rolling temperatures (room temperature and 580 °C). Then, the rolled sheet materials were bent using 3 different bending die angles (60°, 90°, 120°). As a result of this study, the greatest plastic deformation was reached at a speed ratio of 2.0 at 580 °C. Again, the lowest springback was obtained at 580 °C. As the die angle increased, the springback decreased. Springback has occurred in the bending process of all sheet materials obtained by rolling. In the bending process of the unrolled sheet material, both spring-forward and springback events were observed depending on the die angle.
{"title":"Finite element analysis of the springback behavior after V bending process of sheet materials obtained by Differential Speed Rolling (DSR) method","authors":"Vedat Taşdemir","doi":"10.3989/revmetalm.219","DOIUrl":"https://doi.org/10.3989/revmetalm.219","url":null,"abstract":"The Differential Speed Rolling (DSR) process is a severe plastic deformation method used in the production of microstructured materials with both high deformation and superior mechanical properties. This study has focused on determining the springback behavior and formability of the materials obtained by using the DSR method after the V bending process. Rolling processes were carried out at 4 different rolling speed ratios (1.0, 1.33, 1.66, and 2.0), 25% thickness reduction ratio, and 2 different rolling temperatures (room temperature and 580 °C). Then, the rolled sheet materials were bent using 3 different bending die angles (60°, 90°, 120°). As a result of this study, the greatest plastic deformation was reached at a speed ratio of 2.0 at 580 °C. Again, the lowest springback was obtained at 580 °C. As the die angle increased, the springback decreased. Springback has occurred in the bending process of all sheet materials obtained by rolling. In the bending process of the unrolled sheet material, both spring-forward and springback events were observed depending on the die angle.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44414859","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 Fahad Riaz, M. Samiuddin, M. Farooq, Intizar Ali Shah
It is an attributed fact that magnesium, in normal conditions, behaves as active or anodic material and steel as a noble or cathodic material in a galvanic cell. In the current study, various experiments have been conducted to investigate the electrochemical behavior of magnesium and mild steel galvanic couples in tap water and 0.1M NaHCO3 corrosive environments at different temperatures (40 ℃ to 80 ℃). The potentiodynamic results have confirmed that in tap water, magnesium acts as an anode as it corrodes itself and protects steel surfaces under the influence of galvanic action at selected temperatures. However, magnesium became passive under 0.1M NaHCO3 making steel anodic, which deteriorates aggressively at higher temperatures in 0.1M NaHCO3. The polarity reversal phenomenon was also observed in the magnesium-steel couple when exposed to this environment. The microstructural examination has shown that passivation occurred due to the formation of an oxide layer that grew towards the steel side in the galvanic couple as the temperature increased. Thus, the study revealed that the magnesium would be more damaging to steel in a NaHCO3 environment if utilized in the temperature range of 60 ℃to 80 ℃.
{"title":"Analysis of Tafel polarization scans of Magnesium-Steel galvanic couple under different corrosive environments at various temperatures","authors":"Muhammad Fahad Riaz, M. Samiuddin, M. Farooq, Intizar Ali Shah","doi":"10.3989/revmetalm.220","DOIUrl":"https://doi.org/10.3989/revmetalm.220","url":null,"abstract":"It is an attributed fact that magnesium, in normal conditions, behaves as active or anodic material and steel as a noble or cathodic material in a galvanic cell. In the current study, various experiments have been conducted to investigate the electrochemical behavior of magnesium and mild steel galvanic couples in tap water and 0.1M NaHCO3 corrosive environments at different temperatures (40 ℃ to 80 ℃). The potentiodynamic results have confirmed that in tap water, magnesium acts as an anode as it corrodes itself and protects steel surfaces under the influence of galvanic action at selected temperatures. However, magnesium became passive under 0.1M NaHCO3 making steel anodic, which deteriorates aggressively at higher temperatures in 0.1M NaHCO3. The polarity reversal phenomenon was also observed in the magnesium-steel couple when exposed to this environment. The microstructural examination has shown that passivation occurred due to the formation of an oxide layer that grew towards the steel side in the galvanic couple as the temperature increased. Thus, the study revealed that the magnesium would be more damaging to steel in a NaHCO3 environment if utilized in the temperature range of 60 ℃to 80 ℃.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43575551","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}
A. Niklas, M. Arenas, S. Méndez, A. Conde, R. González-Martínez, J. D. de Damborenea, J. Sertucha
The corrosion control of ductile cast irons becomes a technological challenge when supplying castings to customers due to the high reactivity of this alloy in contact with air. An interesting alternative to the protective systems such as coatings or corrosion inhibitors included in packaging processes is the chemical modification of the cast alloys by means of alloying elements addition which are able to improve the corrosion resistance of ductile cast irons. Ni, Cr and Al added to the cast alloys significantly affect their structure and properties, among them their corrosion response, when exposed to air. It has been observed that Ni and Al improve the corrosion behaviour while Cr additionally promoted pearlite and carbides formation. The results from the corrosion tests performed on ductile cast iron alloys which contain these three elements are discussed in the present work.
{"title":"Effect of alloying with Ni, Cr and Al on the atmospheric and electrochemical corrosion resistance of ferritic ductile cast irons","authors":"A. Niklas, M. Arenas, S. Méndez, A. Conde, R. González-Martínez, J. D. de Damborenea, J. Sertucha","doi":"10.3989/revmetalm.216","DOIUrl":"https://doi.org/10.3989/revmetalm.216","url":null,"abstract":"The corrosion control of ductile cast irons becomes a technological challenge when supplying castings to customers due to the high reactivity of this alloy in contact with air. An interesting alternative to the protective systems such as coatings or corrosion inhibitors included in packaging processes is the chemical modification of the cast alloys by means of alloying elements addition which are able to improve the corrosion resistance of ductile cast irons. Ni, Cr and Al added to the cast alloys significantly affect their structure and properties, among them their corrosion response, when exposed to air. It has been observed that Ni and Al improve the corrosion behaviour while Cr additionally promoted pearlite and carbides formation. The results from the corrosion tests performed on ductile cast iron alloys which contain these three elements are discussed in the present work.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44021365","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}
Se ha investigado los efectos de diferentes parámetros de tratamiento térmico y criogénico como la temperatura y el tiempo de mantenimiento sobre la microestructura (cantidad de austenita retenida) y la dureza de moldes de extrusión producidos a partir de los aceros 21NiCrMo2 y 100Cr6. La matriz de extrusión del acero 21NiCrMo2 se cementó durante 22,5 h en una atmósfera de gas (25% CO, 35% N2, 40% H2) a 920 °C. Al final del proceso de cementación, la temperatura se mantuvo a 850 °C, que es la temperatura de austenización, durante 2 h, seguido de enfriamiento en aceite a 80 °C, permaneciendo en aceite durante 45 minutos. No se realizó este proceso de cementación para los moldes de extrusión fabricados con el acero 100Cr6. En este acero solo se llevó a cabo el tratamiento de austenización a la temperatura de 850 °C (manteniendo durante 2 h). Los moldes de acero que se fabricaron con aceros los 21NiCrMo2 y 100Cr6 se trataron posteriormente de manera criogénica a -120 °C durante 2 h y, posteriormente, se templaron a 150 °C durante 1,5 h. Como resultado del tratamiento criogénico, la dureza del acero 21NiCrMo2 aumentó hasta los 840 Hv y mejoró la resistencia al desgaste de la superficie de la matriz de extrusión. La cantidad de austenita residual disminuyó del 20% al 6% después del tratamiento criogénico. Por efecto del proceso criogénico, la dureza superficial de la muestra de acero 100Cr6 aumentó a ~870 Hv, lo que supone un incremento del 4,5%, debido a la transformación de la austenita residual a martensita. La pérdida de masa durante el ensayo de desgaste de las matrices de extrusión endurecidas se redujo de 0,1420 mg a 0,0221 mg. El valor de resistencia al impacto medido en esta condición fue de 20 J. El acero 100Cr6 después del tratamiento criogénico se usó para extruir 12 toneladas de aleación de Al en una prensa industrial. Esta cantidad de material es un 30% inferior a la del acero para herramientas para trabajo en caliente. Por otro lado, el acero 100Cr6 es más económico y el tratamiento térmico es más práctico. El rendimiento durante el proceso de extrusión del acero 21NiCrMo2 fue un 50% inferior al del acero para herramientas de trabajo en caliente.
{"title":"Resistencia al desgaste y rendimiento durante procesos de extrusión a escala industrial de los aceros 100Cr6 y 21NiCrMo2 sometidos a tratamientos criogénicos","authors":"Bahadır Karaca, Levent Cenk Kumruoğlu","doi":"10.3989/revmetalm.212","DOIUrl":"https://doi.org/10.3989/revmetalm.212","url":null,"abstract":" \u0000Se ha investigado los efectos de diferentes parámetros de tratamiento térmico y criogénico como la temperatura y el tiempo de mantenimiento sobre la microestructura (cantidad de austenita retenida) y la dureza de moldes de extrusión producidos a partir de los aceros 21NiCrMo2 y 100Cr6. La matriz de extrusión del acero 21NiCrMo2 se cementó durante 22,5 h en una atmósfera de gas (25% CO, 35% N2, 40% H2) a 920 °C. Al final del proceso de cementación, la temperatura se mantuvo a 850 °C, que es la temperatura de austenización, durante 2 h, seguido de enfriamiento en aceite a 80 °C, permaneciendo en aceite durante 45 minutos. No se realizó este proceso de cementación para los moldes de extrusión fabricados con el acero 100Cr6. En este acero solo se llevó a cabo el tratamiento de austenización a la temperatura de 850 °C (manteniendo durante 2 h). Los moldes de acero que se fabricaron con aceros los 21NiCrMo2 y 100Cr6 se trataron posteriormente de manera criogénica a -120 °C durante 2 h y, posteriormente, se templaron a 150 °C durante 1,5 h. Como resultado del tratamiento criogénico, la dureza del acero 21NiCrMo2 aumentó hasta los 840 Hv y mejoró la resistencia al desgaste de la superficie de la matriz de extrusión. La cantidad de austenita residual disminuyó del 20% al 6% después del tratamiento criogénico. Por efecto del proceso criogénico, la dureza superficial de la muestra de acero 100Cr6 aumentó a ~870 Hv, lo que supone un incremento del 4,5%, debido a la transformación de la austenita residual a martensita. La pérdida de masa durante el ensayo de desgaste de las matrices de extrusión endurecidas se redujo de 0,1420 mg a 0,0221 mg. El valor de resistencia al impacto medido en esta condición fue de 20 J. El acero 100Cr6 después del tratamiento criogénico se usó para extruir 12 toneladas de aleación de Al en una prensa industrial. Esta cantidad de material es un 30% inferior a la del acero para herramientas para trabajo en caliente. Por otro lado, el acero 100Cr6 es más económico y el tratamiento térmico es más práctico. El rendimiento durante el proceso de extrusión del acero 21NiCrMo2 fue un 50% inferior al del acero para herramientas de trabajo en caliente.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44526791","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}
Se ha estudiado el comportamiento tribológico de materiales compuestos de matriz metálica de aluminio (AA5083)/nano-Al2O3 con un porcentaje de refuerzo variable de 2, 4, 6 y 8% en peso de partículas de nano-Al2O3. Los compuestos Al/nano-Al2O3 se prepararon utilizando una ruta de colada por agitación. Las imágenes de microscopía electrónica de barrido (MEB) de los materiales sugirieron una dispersión casi uniforme de las nanopartículas en la matriz de Al. El comportamiento al desgaste por deslizamiento se estudió utilizando un banco de pruebas pin-on-disc. El plan de experimentos tuvo como referencia la matriz ortogonal L25 de Taguchi utilizando tres parámetros de proceso en cinco niveles, a saber, porcentaje en peso de refuerzo, carga aplicada y distancia de deslizamiento. Los resultados obtenidos revelan que los materiales compuestos reforzados con nanopartículas presentan una mejor resistencia al desgaste. Mientras que la gráfica de efectos principales sugirió que el desgaste aumenta con un aumento en la carga, la distancia de deslizamiento y disminuye con un aumento en el porcentaje de refuerzo. El análisis de varianza (ANOVA) ilustró que la distancia de deslizamiento fue el parámetro más significativo. La morfología de la superficie desgastada del espécimen probado, bajo la condición de carga más alta, reveló la ocurrencia de un fenómeno de desgaste abrasivo.
{"title":"Investigación del comportamiento al desgaste por deslizamiento en seco de materiales compuestos de matriz metálica AA5083/NANO-Al2O3","authors":"R. Suresh, G. Joshi Ajith, N.G. Siddeshkumar","doi":"10.3989/revmetalm.213","DOIUrl":"https://doi.org/10.3989/revmetalm.213","url":null,"abstract":"Se ha estudiado el comportamiento tribológico de materiales compuestos de matriz metálica de aluminio (AA5083)/nano-Al2O3 con un porcentaje de refuerzo variable de 2, 4, 6 y 8% en peso de partículas de nano-Al2O3. Los compuestos Al/nano-Al2O3 se prepararon utilizando una ruta de colada por agitación. Las imágenes de microscopía electrónica de barrido (MEB) de los materiales sugirieron una dispersión casi uniforme de las nanopartículas en la matriz de Al. El comportamiento al desgaste por deslizamiento se estudió utilizando un banco de pruebas pin-on-disc. El plan de experimentos tuvo como referencia la matriz ortogonal L25 de Taguchi utilizando tres parámetros de proceso en cinco niveles, a saber, porcentaje en peso de refuerzo, carga aplicada y distancia de deslizamiento. Los resultados obtenidos revelan que los materiales compuestos reforzados con nanopartículas presentan una mejor resistencia al desgaste. Mientras que la gráfica de efectos principales sugirió que el desgaste aumenta con un aumento en la carga, la distancia de deslizamiento y disminuye con un aumento en el porcentaje de refuerzo. El análisis de varianza (ANOVA) ilustró que la distancia de deslizamiento fue el parámetro más significativo. La morfología de la superficie desgastada del espécimen probado, bajo la condición de carga más alta, reveló la ocurrencia de un fenómeno de desgaste abrasivo.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42051274","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}
El titanio (Ti) y sus aleaciones se encuentran entre los materiales más utilizados en aplicaciones biomédicas. Además de ser biocompatibles, estos materiales tienen una baja densidad, una alta resistencia a la corrosión y unas propiedades mecánicas notables. Es muy difícil producir piezas con geometría compleja utilizando métodos convencionales de pulvimetalurgia (PM) ya que este método se basa en dar forma a polvos bajo fuerzas uniaxiales utilizando moldes. La Inyección Aglutinante (Binder Jetting) es un tipo de técnica de fabricación aditiva que no necesita moldes para dar forma a los polvos. Este estudio se centra en comparar las propiedades de las piezas porosas de CP-Ti producidas con PM e Inyección Aglutinante. Las piezas se sinterizaron durante 120 min en una atmósfera de argón a 1200 °C. Después de la sinterización, se alcanzaron valores de densidad relativa de aproximadamente el 94% y el 92% en las muestras producidas por PM y con la impresora 3D, respectivamente. También se observó que la muestra producida con una presión de compactación de 25 MPa tiene una dureza de 317 ± 10 HV0.05 y un límite elástico bajo compresión de 928 MPa, mientras que la pieza producida con la impresora 3D tiene una dureza de 238 ± 8 HV0. 05 y un límite elástico bajo compresión de 342 MPa. Aunque la dureza y resistencia de las muestras producidas con la impresora 3D fueron menores que las de PM, sus propiedades son adecuadas para producir implantes que reemplacen las estructuras óseas.
{"title":"Caracterización de CP-Titanio producido mediante inyección aglutinante y pulvimetalurgia convencional","authors":"Osman İyibilgin, Engin Gepek","doi":"10.3989/revmetalm.205","DOIUrl":"https://doi.org/10.3989/revmetalm.205","url":null,"abstract":"El titanio (Ti) y sus aleaciones se encuentran entre los materiales más utilizados en aplicaciones biomédicas. Además de ser biocompatibles, estos materiales tienen una baja densidad, una alta resistencia a la corrosión y unas propiedades mecánicas notables. Es muy difícil producir piezas con geometría compleja utilizando métodos convencionales de pulvimetalurgia (PM) ya que este método se basa en dar forma a polvos bajo fuerzas uniaxiales utilizando moldes. La Inyección Aglutinante (Binder Jetting) es un tipo de técnica de fabricación aditiva que no necesita moldes para dar forma a los polvos. Este estudio se centra en comparar las propiedades de las piezas porosas de CP-Ti producidas con PM e Inyección Aglutinante. Las piezas se sinterizaron durante 120 min en una atmósfera de argón a 1200 °C. Después de la sinterización, se alcanzaron valores de densidad relativa de aproximadamente el 94% y el 92% en las muestras producidas por PM y con la impresora 3D, respectivamente. También se observó que la muestra producida con una presión de compactación de 25 MPa tiene una dureza de 317 ± 10 HV0.05 y un límite elástico bajo compresión de 928 MPa, mientras que la pieza producida con la impresora 3D tiene una dureza de 238 ± 8 HV0. 05 y un límite elástico bajo compresión de 342 MPa. Aunque la dureza y resistencia de las muestras producidas con la impresora 3D fueron menores que las de PM, sus propiedades son adecuadas para producir implantes que reemplacen las estructuras óseas.","PeriodicalId":21206,"journal":{"name":"Revista De Metalurgia","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42954999","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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