Magnesium and its alloys display a non-usual relationship between flow stress and grain size at room temperature. Breaks in the Hall-Petch relationship have been reported in the literature. Inverse Hall-Petch behavior in which flow stress reduces with grain size decreasing has also been reported in pure magnesium and magnesium alloys with ultrafine and nanocrystalline structures. The present overview discusses these effects in terms of controlling deformation mechanisms. The distinct strength observed in pure magnesium and magnesium alloys with ultrafine grained structure is also discussed. It is shown that experimental data for fine and ultrafine grained magnesium alloys agree with a model suggested recently based on the mechanism of grain boundary sliding. It is also exhibited that the stability of the grain structure might control the strength of ultrafine grained samples.
{"title":"Breaks in Hall-Petch Relationship in Magnesium","authors":"Amanda P. Carvalho, R. Figueiredo","doi":"10.4028/p-8qxhof","DOIUrl":"https://doi.org/10.4028/p-8qxhof","url":null,"abstract":"Magnesium and its alloys display a non-usual relationship between flow stress and grain size at room temperature. Breaks in the Hall-Petch relationship have been reported in the literature. Inverse Hall-Petch behavior in which flow stress reduces with grain size decreasing has also been reported in pure magnesium and magnesium alloys with ultrafine and nanocrystalline structures. The present overview discusses these effects in terms of controlling deformation mechanisms. The distinct strength observed in pure magnesium and magnesium alloys with ultrafine grained structure is also discussed. It is shown that experimental data for fine and ultrafine grained magnesium alloys agree with a model suggested recently based on the mechanism of grain boundary sliding. It is also exhibited that the stability of the grain structure might control the strength of ultrafine grained samples.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"121 31","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138599643","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}
A novel procedure for material quality assessment developed for castings like ductile irons and Al alloys, is based on the analysis of tensile strain hardening through dislocation-density-related constitutive equation, and consists of plotting the Voce equation parameters found through modeling the tensile flow curves with the Voce constitutive equation. In sound materials the Voce parameters have a regular trend, consistent with the physical meaning of the dislocation-density-related Voce constitutive equation. The Voce parameters identify a regular trend also in defective materials, even if defects and metallurgical discontinuities might be expected to add a random and unpredictable component to the plastic behavior. This unexpected regular behavior in defective materials has been called as Defects-Driven Plasticity (DDP), and its rationalization seems to be possible by coupling the concepts of Notch Strengthening (NS) of defects, and stable ductile fracture propagation of the Continuous Damage Mechanics (CDM). The rationalization of DDP and the experimental findings to support, are here reported in high Silicon strengthened ductile irons.
{"title":"Defects-Driven Plasticity: Rationalization Based on Notch Strengthening and Continuous Damage Mechanics","authors":"G. Angella, F. Zanardi","doi":"10.4028/p-de4q1j","DOIUrl":"https://doi.org/10.4028/p-de4q1j","url":null,"abstract":"A novel procedure for material quality assessment developed for castings like ductile irons and Al alloys, is based on the analysis of tensile strain hardening through dislocation-density-related constitutive equation, and consists of plotting the Voce equation parameters found through modeling the tensile flow curves with the Voce constitutive equation. In sound materials the Voce parameters have a regular trend, consistent with the physical meaning of the dislocation-density-related Voce constitutive equation. The Voce parameters identify a regular trend also in defective materials, even if defects and metallurgical discontinuities might be expected to add a random and unpredictable component to the plastic behavior. This unexpected regular behavior in defective materials has been called as Defects-Driven Plasticity (DDP), and its rationalization seems to be possible by coupling the concepts of Notch Strengthening (NS) of defects, and stable ductile fracture propagation of the Continuous Damage Mechanics (CDM). The rationalization of DDP and the experimental findings to support, are here reported in high Silicon strengthened ductile irons.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"111 24","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138599734","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}
Abhijit Cholkar, Suman Chatterjee, David Kinahan, D. Brabazon
Aluminium alloy 6061 has a versatile application within industrial heat exchangers, heat sinks, chemical equipment, and frames of aircraft and ships. Its physical and mechanical properties such as lightweight, high strength, corrosion resistance, and thermal and electrical conductivity make it a suitable material choice for these applications. Within thermal and micro-electromechanical applications, such as heat exchanges, radiators, and heat sinks used in microelectronics, the dissipation of heat plays an important role. For optimum heat dissipation, a higher surface area is required. This can be achieved by modifying the surface by fabricating microchannels. A number of processing techniques are used for fabricating microchannels on different materials. A laser is a flexible non-contact machining tool that may be used to create any profile or contour on practically any material. In recent times due to the advancement in laser technology, the use of ultrafast laser material processing is one potential route toward further extending the fabrication of high-quality microchannels without defects caused due to heat-affected zones and in a sustainable manner. In this paper, we present an experimental work of fabrication of microchannels on an aluminium alloy 6061 surfaces by using a low power (<4 W) 400 fs laser system. The dimensional accuracy of the fabricated microchannels is assessed using scanning electron microscopy and 3D profilometry. Furthermore, as processing speed and scale is of importance in industrial laser processes, the use of scanning optics is examined as a means of developing a rapid and scalable ultrafast laser process.
{"title":"Ultrafast Laser Fabrication of Microchannels on Aluminium Alloy Substrate","authors":"Abhijit Cholkar, Suman Chatterjee, David Kinahan, D. Brabazon","doi":"10.4028/p-rjfpy3","DOIUrl":"https://doi.org/10.4028/p-rjfpy3","url":null,"abstract":"Aluminium alloy 6061 has a versatile application within industrial heat exchangers, heat sinks, chemical equipment, and frames of aircraft and ships. Its physical and mechanical properties such as lightweight, high strength, corrosion resistance, and thermal and electrical conductivity make it a suitable material choice for these applications. Within thermal and micro-electromechanical applications, such as heat exchanges, radiators, and heat sinks used in microelectronics, the dissipation of heat plays an important role. For optimum heat dissipation, a higher surface area is required. This can be achieved by modifying the surface by fabricating microchannels. A number of processing techniques are used for fabricating microchannels on different materials. A laser is a flexible non-contact machining tool that may be used to create any profile or contour on practically any material. In recent times due to the advancement in laser technology, the use of ultrafast laser material processing is one potential route toward further extending the fabrication of high-quality microchannels without defects caused due to heat-affected zones and in a sustainable manner. In this paper, we present an experimental work of fabrication of microchannels on an aluminium alloy 6061 surfaces by using a low power (<4 W) 400 fs laser system. The dimensional accuracy of the fabricated microchannels is assessed using scanning electron microscopy and 3D profilometry. Furthermore, as processing speed and scale is of importance in industrial laser processes, the use of scanning optics is examined as a means of developing a rapid and scalable ultrafast laser process.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"31 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138600997","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}
Hiroyuki Y. Yasuda, Masaki Horiguchi, Ken Cho, Takahiro Masuda, Takeshi Nagase
In Cr-rich CoCrFeMnNi alloys, the precipitation of the σ phase at grain boundaries during recrystallization is so fast that ultrafine-grained structure is formed due to the pinning effect of the precipitates. The average grain size of the fcc parent phase is found to be consistent with modified Zener-Smith model. If conventional alloys come to equilibrium, volume fraction of precipitates should approach a saturation value. However, it is interesting to note that the volume fraction of the σ phase in Cr-rich CoCrFeMnNi alloys is inversely proportional to the average grain size of the fcc parent phase. For instance, in Co20Cr25Fe20Ni15Mn20 alloys, the volume fraction changes from 6.5% to 1.2% with increasing average gran size from 14 μm to 210 μm even after annealing at 1273 K for 100 h. It is well known that heterogeneous nucleation of precipitates at grain boundary is energetically favorable and fast diffusion through grain boundary can assist the precipitation. However, they cannot account for the grain size dependence of the volume fraction after reaching equilibrium. Based on stereology, the reciprocal of grain size is proportional to grain boundary area. Thus, chemical fluctuation at grain boundaries (e.g. segregation) is considered to be related to the unusual precipitation at the grain boundaries.
{"title":"Unusual Precipitation at Grain Boundaries in Non-Equiatomic CoCrFeMnNi High Entropy Alloys","authors":"Hiroyuki Y. Yasuda, Masaki Horiguchi, Ken Cho, Takahiro Masuda, Takeshi Nagase","doi":"10.4028/p-4knuld","DOIUrl":"https://doi.org/10.4028/p-4knuld","url":null,"abstract":"In Cr-rich CoCrFeMnNi alloys, the precipitation of the σ phase at grain boundaries during recrystallization is so fast that ultrafine-grained structure is formed due to the pinning effect of the precipitates. The average grain size of the fcc parent phase is found to be consistent with modified Zener-Smith model. If conventional alloys come to equilibrium, volume fraction of precipitates should approach a saturation value. However, it is interesting to note that the volume fraction of the σ phase in Cr-rich CoCrFeMnNi alloys is inversely proportional to the average grain size of the fcc parent phase. For instance, in Co20Cr25Fe20Ni15Mn20 alloys, the volume fraction changes from 6.5% to 1.2% with increasing average gran size from 14 μm to 210 μm even after annealing at 1273 K for 100 h. It is well known that heterogeneous nucleation of precipitates at grain boundary is energetically favorable and fast diffusion through grain boundary can assist the precipitation. However, they cannot account for the grain size dependence of the volume fraction after reaching equilibrium. Based on stereology, the reciprocal of grain size is proportional to grain boundary area. Thus, chemical fluctuation at grain boundaries (e.g. segregation) is considered to be related to the unusual precipitation at the grain boundaries.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"121 39","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138599637","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}
Magnesium alloys have the advantages being lightweight and high recyclability. On the other hands, it is thought that magnesium has the disadvantage of poor plastic workability at room temperature due to its crystal structure. Especially, in pipe materials, winkles occur on the compressed side during bending. We aim to improve the bending workability in magnesium alloy pipe by torsion and back-torsion. In this study, tensile and compressive tests using specimens of pipes processed by torsion and back-torsion showed reduction the difference of yield stress. Microstructural observation of processed pipes revealed reducing crystal grain size and forming deformation twinning. Vickers hardness tests shows increasing hardness by torsion and back-torsion. Moreover, bending tests showed decreasing flatting ratio by torsion and back-torsion. These results demonstrated that torsion and back-torsion have effect of improvement in bending workability for magnesium alloy pipes.
{"title":"Factor for Improvement of Plastic Workability in Magnesium Alloy Pipes through Processing by Torsion and Back-Torsion","authors":"Hayata Okazaki, T. Kato, M. Furui","doi":"10.4028/p-dtd09z","DOIUrl":"https://doi.org/10.4028/p-dtd09z","url":null,"abstract":"Magnesium alloys have the advantages being lightweight and high recyclability. On the other hands, it is thought that magnesium has the disadvantage of poor plastic workability at room temperature due to its crystal structure. Especially, in pipe materials, winkles occur on the compressed side during bending. We aim to improve the bending workability in magnesium alloy pipe by torsion and back-torsion. In this study, tensile and compressive tests using specimens of pipes processed by torsion and back-torsion showed reduction the difference of yield stress. Microstructural observation of processed pipes revealed reducing crystal grain size and forming deformation twinning. Vickers hardness tests shows increasing hardness by torsion and back-torsion. Moreover, bending tests showed decreasing flatting ratio by torsion and back-torsion. These results demonstrated that torsion and back-torsion have effect of improvement in bending workability for magnesium alloy pipes.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"82 13","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138600196","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}
Titanium and its alloys are the 5th most common metallic materials used world wide but the markets volume of titanium materials, is difficult to expand due to associated production costs, and the decrease of those costs are critical in order to expand their markets. A possible option is the alloy design, i.e. using low price alloying element, such as iron, chromium, manganese and oxygen, and the selection of other raw materials, i.e. grade of sponge titanium. In beta titanium alloy, Ti-Mo system alloy using ferro-molybdeum was developed by USA company or Ti-Cr-Fe-Al beta alloy were also developed by Japan company. In this paper, those developed alloys were explained. Furthermore, substitution of Ti-10V-2Fe-3Al near beta alloy, presenters are studying about Ti-Mn-Fe-Al alloy.
{"title":"Developments of Cost Affordable Titanium Alloys in Japan","authors":"Masahiko Ikeda, Masato Ueda, Yusuke Yamanishi","doi":"10.4028/p-n1iiyw","DOIUrl":"https://doi.org/10.4028/p-n1iiyw","url":null,"abstract":"Titanium and its alloys are the 5th most common metallic materials used world wide but the markets volume of titanium materials, is difficult to expand due to associated production costs, and the decrease of those costs are critical in order to expand their markets. A possible option is the alloy design, i.e. using low price alloying element, such as iron, chromium, manganese and oxygen, and the selection of other raw materials, i.e. grade of sponge titanium. In beta titanium alloy, Ti-Mo system alloy using ferro-molybdeum was developed by USA company or Ti-Cr-Fe-Al beta alloy were also developed by Japan company. In this paper, those developed alloys were explained. Furthermore, substitution of Ti-10V-2Fe-3Al near beta alloy, presenters are studying about Ti-Mn-Fe-Al alloy.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"28 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138601101","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}
Jong Min Kim, Tae Kyu Ha, Beom Suck Han, Young Jig Kim
Open-cell type aluminum foam possesses unique structural characteristics comprising numerous interconnected pores within. This intriguing structure facilitates the passage of fluids (gas or liquid) through the interior of the open-cell type aluminum foams, enabling easy transfer to the exterior. The objective of this study is to manufacture open-cell type aluminum foams with varying pore sizes using the replication casting process and to evaluate their thermal properties. The equipment designed for the production of open-cell type aluminum foams consists of a chamber and an inner container. The chamber is connected to a vacuum line and an Ar gas line, with the container positioned inside. The aluminum alloys utilized for the foams were A356 and ADC12, and Na2CO3 served as the space holder. As a result of manufacturing the foams, there was no significant difference of porosity with space holder size and alloy types, the porosity averaged around 62%. To investigate the thermal properties of open-cell type aluminum foams in relation to pore size and alloy types, temperature variations were measured during sample heating via the hot plate method. Consequently, it was confirmed that the thermal properties of the foams were influenced by the structural conditions and alloy types.
{"title":"Manufacturing Method and Thermal Properties of Open-Cell Type Aluminum Foam by Replication Casting Process","authors":"Jong Min Kim, Tae Kyu Ha, Beom Suck Han, Young Jig Kim","doi":"10.4028/p-g8exke","DOIUrl":"https://doi.org/10.4028/p-g8exke","url":null,"abstract":"Open-cell type aluminum foam possesses unique structural characteristics comprising numerous interconnected pores within. This intriguing structure facilitates the passage of fluids (gas or liquid) through the interior of the open-cell type aluminum foams, enabling easy transfer to the exterior. The objective of this study is to manufacture open-cell type aluminum foams with varying pore sizes using the replication casting process and to evaluate their thermal properties. The equipment designed for the production of open-cell type aluminum foams consists of a chamber and an inner container. The chamber is connected to a vacuum line and an Ar gas line, with the container positioned inside. The aluminum alloys utilized for the foams were A356 and ADC12, and Na2CO3 served as the space holder. As a result of manufacturing the foams, there was no significant difference of porosity with space holder size and alloy types, the porosity averaged around 62%. To investigate the thermal properties of open-cell type aluminum foams in relation to pore size and alloy types, temperature variations were measured during sample heating via the hot plate method. Consequently, it was confirmed that the thermal properties of the foams were influenced by the structural conditions and alloy types.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"68 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138598239","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}
This contribution presents a study on the effect of heating rate maintained during annealing treatment on the final microstructure and mechanical properties of cold rolled Al1050 sheet. This study is focused on microstructure and texture evolution of Al1050 annealed at various heating rates, annealing temperatures, and holding times. It was observed that the longer exposure time for deformed microstructure affects the Vickers hardness values, grain size, and texture intensity. It seems that the crystallographic texture evolution is not affected by heating rate on quantitative level since the same set of orientations tended to evolve in all studied cases. The sample annealed at slow heating rate in a box-type furnace produced recrystallized microstructure with fine grain size, and comparatively lower texture intensity & hardness.
{"title":"Effect of Heating Rate on the Annealing Behavior of Aluminium Alloys","authors":"P. Chakravarty, J. J. Sidor","doi":"10.4028/p-31wxmv","DOIUrl":"https://doi.org/10.4028/p-31wxmv","url":null,"abstract":"This contribution presents a study on the effect of heating rate maintained during annealing treatment on the final microstructure and mechanical properties of cold rolled Al1050 sheet. This study is focused on microstructure and texture evolution of Al1050 annealed at various heating rates, annealing temperatures, and holding times. It was observed that the longer exposure time for deformed microstructure affects the Vickers hardness values, grain size, and texture intensity. It seems that the crystallographic texture evolution is not affected by heating rate on quantitative level since the same set of orientations tended to evolve in all studied cases. The sample annealed at slow heating rate in a box-type furnace produced recrystallized microstructure with fine grain size, and comparatively lower texture intensity & hardness.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"108 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138599741","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}
It is now well established that the grain size is the fundamental microstructural feature of all polycrystalline materials. In practice, a very wide range of grain sizes will be needed in order to fully evaluate the effect of grain size on the mechanical properties of metals. For many years this was a significant limitation because it was not possible to use conventional thermomechanical processing to produce materials with submicrometer or nanometer grain sizes. Recently, this problem has been addressed by developing alternative processing techniques based on the application of severe plastic deformation. This overview demonstrates that, although the flow stress increases with decreasing grain size at low temperatures and decreases with decreasing grain size at high temperatures, this clear dichotomy in behavior may be adequately explained by using a single theoretical flow mechanism based on the occurrence of grain boundary sliding.
{"title":"The Role of Grain Size in the Mechanical Properties of Metals","authors":"M. Kawasaki, R. Figueiredo, Terence G. Langdon","doi":"10.4028/p-d7em1c","DOIUrl":"https://doi.org/10.4028/p-d7em1c","url":null,"abstract":"It is now well established that the grain size is the fundamental microstructural feature of all polycrystalline materials. In practice, a very wide range of grain sizes will be needed in order to fully evaluate the effect of grain size on the mechanical properties of metals. For many years this was a significant limitation because it was not possible to use conventional thermomechanical processing to produce materials with submicrometer or nanometer grain sizes. Recently, this problem has been addressed by developing alternative processing techniques based on the application of severe plastic deformation. This overview demonstrates that, although the flow stress increases with decreasing grain size at low temperatures and decreases with decreasing grain size at high temperatures, this clear dichotomy in behavior may be adequately explained by using a single theoretical flow mechanism based on the occurrence of grain boundary sliding.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"110 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138599803","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}
In order to get the insights about microstructural changes that occurs under the thermo-mechanical processing conditions, the physics based modelling approach is very useful. Therefore, the flow curves of alloy 718 are theoretical simulated using a dislocation density dependent constitutive model for different conditions. Presented model considers the microstructural ingredients that are immobile dislocation density, effective grain size and dislocation cell size as the variables to address the creep. The simulated flow curves show a good agreement with the experimental flow curves. The magnitude of immobile dislocation density and dislocation cell size in between 3.87× 1014 - 3.87× 1014 m-2 and 8.29-8.45 μm, respectively, at the completion of the simulation. Furthermore, this approach also provides the possibility to quantify and depict the variation in each strengthening contributions.
{"title":"Microstructure Based Flow Stress Modelling of Superalloy 718","authors":"Nilesh Kumar, S. D. Yadav","doi":"10.4028/p-alg9hs","DOIUrl":"https://doi.org/10.4028/p-alg9hs","url":null,"abstract":"In order to get the insights about microstructural changes that occurs under the thermo-mechanical processing conditions, the physics based modelling approach is very useful. Therefore, the flow curves of alloy 718 are theoretical simulated using a dislocation density dependent constitutive model for different conditions. Presented model considers the microstructural ingredients that are immobile dislocation density, effective grain size and dislocation cell size as the variables to address the creep. The simulated flow curves show a good agreement with the experimental flow curves. The magnitude of immobile dislocation density and dislocation cell size in between 3.87× 1014 - 3.87× 1014 m-2 and 8.29-8.45 μm, respectively, at the completion of the simulation. Furthermore, this approach also provides the possibility to quantify and depict the variation in each strengthening contributions.","PeriodicalId":21754,"journal":{"name":"Solid State Phenomena","volume":"92 14","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138600173","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}