Pub Date : 2023-07-04DOI: 10.1080/00325899.2023.2230688
Dong Hoon Lee, Seungheon Han, Manho Park, J. Yun, Myeongjun Ji, Young‐In Lee
ABSTRACT Today, microfiltration plays the most significant role in removing fine particulate impurities in gas streams used in high-tech industries. However, the current SS316L gas filter has a limitation in enhancing performance due to the trade-off relationship between filterability and permeability. This limitation can be overcome by the geometrical effect of the gas filter that maximises inertial impaction and diffusion interception due to complex flow channels using small flake particles. However, since the smaller the particle size, the yield strength higher, there are few reports of preparing the small flake particles by plastic deformation. This study used a high-energy ball milling process to demonstrate the preparation method for small stainless steel 316L flake particles. Furthermore, the process parameters are systematically optimised to fully transform the spherical particles into thin platelets without fracture and cold welding, and the transformation behaviour is discussed in detail.
{"title":"Morphology transformation of stainless steel 316L powder from spheres to flakes using high-energy ball milling and the investigation of transformation behaviour","authors":"Dong Hoon Lee, Seungheon Han, Manho Park, J. Yun, Myeongjun Ji, Young‐In Lee","doi":"10.1080/00325899.2023.2230688","DOIUrl":"https://doi.org/10.1080/00325899.2023.2230688","url":null,"abstract":"ABSTRACT Today, microfiltration plays the most significant role in removing fine particulate impurities in gas streams used in high-tech industries. However, the current SS316L gas filter has a limitation in enhancing performance due to the trade-off relationship between filterability and permeability. This limitation can be overcome by the geometrical effect of the gas filter that maximises inertial impaction and diffusion interception due to complex flow channels using small flake particles. However, since the smaller the particle size, the yield strength higher, there are few reports of preparing the small flake particles by plastic deformation. This study used a high-energy ball milling process to demonstrate the preparation method for small stainless steel 316L flake particles. Furthermore, the process parameters are systematically optimised to fully transform the spherical particles into thin platelets without fracture and cold welding, and the transformation behaviour is discussed in detail.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48400949","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}
Pub Date : 2023-07-04DOI: 10.1080/00325899.2023.2230693
Dinh Van Cong, Dong-Wan Lee, Su-Gwan Lee, Jin-Woo Kim, hwi-Jun KiM, Joong-Gyeong Lim, T. Yoon, Jin-Chun Kim
ABSTRACT The present study investigates the properties and microstructure evolution of MA 6000, a nickel-based alloy produced by mechanical alloying and spark plasma sintering (SPS), a powder processing technique in metallurgy. This study aims to explore the potential of MA 6000 as a high-temperature material for industrial applications. Modified MA 6000 samples of different powder sizes were sintered in a high-vacuum environment at temperatures ranging from 800 to 1100°C. At 800°C, the cohesion between powder particles was not significant, resulting in low-density samples. However, at 1000°C, the samples consisted of many fully sintered regions related to finer powder particles, while no specific morphology was observed at 1050°C. The image quality and inverse pole figure (IQ-IPF) map indicated that the grains were distributed randomly in all sintered samples, and the average distribution of grain size of samples sintered at 1050°C was larger than that of those sintered at 1000°C.
{"title":"The effects of powder size and sintering temperature on the microstructure and properties of modified MA6000 alloy produced by spark plasma sintering","authors":"Dinh Van Cong, Dong-Wan Lee, Su-Gwan Lee, Jin-Woo Kim, hwi-Jun KiM, Joong-Gyeong Lim, T. Yoon, Jin-Chun Kim","doi":"10.1080/00325899.2023.2230693","DOIUrl":"https://doi.org/10.1080/00325899.2023.2230693","url":null,"abstract":"ABSTRACT\u0000 The present study investigates the properties and microstructure evolution of MA 6000, a nickel-based alloy produced by mechanical alloying and spark plasma sintering (SPS), a powder processing technique in metallurgy. This study aims to explore the potential of MA 6000 as a high-temperature material for industrial applications. Modified MA 6000 samples of different powder sizes were sintered in a high-vacuum environment at temperatures ranging from 800 to 1100°C. At 800°C, the cohesion between powder particles was not significant, resulting in low-density samples. However, at 1000°C, the samples consisted of many fully sintered regions related to finer powder particles, while no specific morphology was observed at 1050°C. The image quality and inverse pole figure (IQ-IPF) map indicated that the grains were distributed randomly in all sintered samples, and the average distribution of grain size of samples sintered at 1050°C was larger than that of those sintered at 1000°C.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48528763","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}
Pub Date : 2023-06-26DOI: 10.1080/00325899.2023.2228093
V. Opini, J. B. Fogagnolo, V. A. Borrás, R. Caram, J. Soyama
ABSTRACT Near β Ti alloys typically show high specific strength and provide a wide spectrum of mechanical properties with different heat treatments. In this work, a commercial near β Ti alloy Ti-5553 (Ti-5Al-5V-5Mo-3Cr-0.5Fe) was prepared through powder metallurgy using the blended elemental powder approach. Additionally, alloy modifications with 6 wt.% Nb (Ti-6Nb-5Al-2.5V-5Mo-3Cr-0.5Fe) and 12 wt.% Nb (Ti-12Nb-5Al-5Mo-3Cr-0.5Fe) were investigated. Specimens were prepared by uniaxial cold compaction of blended powders at room temperature with sintering conducted at 1300°C for 2 h under Ar atmosphere. Microstructure investigation revealed reasonable homogenisation of alloying elements and colony sizes in the order of 80-100 μm with porosity below 10%. Moreover, the bending strength of as-sintered Ti-12Nb-5Al-5Mo-3Cr-0.5Fe was about 850 MPa and the micro-Vickers hardness was approximately 370 HV. The alloy modifications with Nb increased strength without loss in flexural strain.
{"title":"Powder metallurgy processing of Nb-modified near β titanium alloys prepared with elemental powders","authors":"V. Opini, J. B. Fogagnolo, V. A. Borrás, R. Caram, J. Soyama","doi":"10.1080/00325899.2023.2228093","DOIUrl":"https://doi.org/10.1080/00325899.2023.2228093","url":null,"abstract":"ABSTRACT Near β Ti alloys typically show high specific strength and provide a wide spectrum of mechanical properties with different heat treatments. In this work, a commercial near β Ti alloy Ti-5553 (Ti-5Al-5V-5Mo-3Cr-0.5Fe) was prepared through powder metallurgy using the blended elemental powder approach. Additionally, alloy modifications with 6 wt.% Nb (Ti-6Nb-5Al-2.5V-5Mo-3Cr-0.5Fe) and 12 wt.% Nb (Ti-12Nb-5Al-5Mo-3Cr-0.5Fe) were investigated. Specimens were prepared by uniaxial cold compaction of blended powders at room temperature with sintering conducted at 1300°C for 2 h under Ar atmosphere. Microstructure investigation revealed reasonable homogenisation of alloying elements and colony sizes in the order of 80-100 μm with porosity below 10%. Moreover, the bending strength of as-sintered Ti-12Nb-5Al-5Mo-3Cr-0.5Fe was about 850 MPa and the micro-Vickers hardness was approximately 370 HV. The alloy modifications with Nb increased strength without loss in flexural strain.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42000989","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}
Pub Date : 2023-06-23DOI: 10.1080/00325899.2023.2226961
Ji Young Kim, Eui Seon Lee, Youn-Ji Heo, Young‐In Lee, Jong-Hoon Byun, Sung-Tag Oh
ABSTRACT The effect of powder characteristics on the sintering behaviour and microstructure of densified W by spark plasma sintering and post-hot isostatic pressing was investigated. W powder was prepared by ultrasonic spray pyrolysis of a W precursor and hydrogen reduction, and a commercially available powder was used for comparison. The synthesised W powders were present in the form of large agglomerates composed of nano-sized particles. The densified specimens prepared by ultrasonic spray pyrolysis showed lower relative density and larger grain size than when commercial powder was sintered under the same conditions. Microstructural observation for the specimen sintered using the powder of ultrasonic spray pyrolysis revealed that the relatively large pores are present along the grain boundaries. The observed microstructural features were discussed by sintering behaviour based on the effect of intra-agglomerate and inter-agglomerate pores in the initial powder on densification and grain growth.
{"title":"Influence of the initial powder characteristic on the densified tungsten microstructure by spark plasma sintering and hot isostatic pressing","authors":"Ji Young Kim, Eui Seon Lee, Youn-Ji Heo, Young‐In Lee, Jong-Hoon Byun, Sung-Tag Oh","doi":"10.1080/00325899.2023.2226961","DOIUrl":"https://doi.org/10.1080/00325899.2023.2226961","url":null,"abstract":"ABSTRACT The effect of powder characteristics on the sintering behaviour and microstructure of densified W by spark plasma sintering and post-hot isostatic pressing was investigated. W powder was prepared by ultrasonic spray pyrolysis of a W precursor and hydrogen reduction, and a commercially available powder was used for comparison. The synthesised W powders were present in the form of large agglomerates composed of nano-sized particles. The densified specimens prepared by ultrasonic spray pyrolysis showed lower relative density and larger grain size than when commercial powder was sintered under the same conditions. Microstructural observation for the specimen sintered using the powder of ultrasonic spray pyrolysis revealed that the relatively large pores are present along the grain boundaries. The observed microstructural features were discussed by sintering behaviour based on the effect of intra-agglomerate and inter-agglomerate pores in the initial powder on densification and grain growth.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43523921","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}
Pub Date : 2023-06-23DOI: 10.1080/00325899.2023.2226944
A. P. Gómez, G. Urretavizcaya, A. Baruj, M. T. Malachevsky
ABSTRACT A method to manufacture a porous Cu–Al–Ni shape memory alloy by powder metallurgy using space holders is presented. Two aluminium powders with different particle morphologies were employed to investigate their influence on phase formation, microstructure and mechanical properties. The variation of the relative amount of space holders in the mixture allows to obtain different porosities. Samples prepared with irregular-shaped aluminium powder include both 18R and 2H martensitic phases and exhibit the shape memory effect and pseudoelastic behaviour under uniaxial compression tests. In contrast, the samples made with aluminium flakes present the α phase accompanying the 18R martensitic phase, and do not exhibit the shape memory effect. Both the aluminium flakes flat shape and the higher proportion of aluminium oxide associated with its larger surface area to volume ratio hindered the interdiffusion of the metals, resulting in an aluminium-depleted martensitic phase surrounded by an aluminium oxide-rich layered structure.
{"title":"Consolidation and properties of porous Cu–Al–Ni shape memory alloys manufactured by powder metallurgy","authors":"A. P. Gómez, G. Urretavizcaya, A. Baruj, M. T. Malachevsky","doi":"10.1080/00325899.2023.2226944","DOIUrl":"https://doi.org/10.1080/00325899.2023.2226944","url":null,"abstract":"ABSTRACT A method to manufacture a porous Cu–Al–Ni shape memory alloy by powder metallurgy using space holders is presented. Two aluminium powders with different particle morphologies were employed to investigate their influence on phase formation, microstructure and mechanical properties. The variation of the relative amount of space holders in the mixture allows to obtain different porosities. Samples prepared with irregular-shaped aluminium powder include both 18R and 2H martensitic phases and exhibit the shape memory effect and pseudoelastic behaviour under uniaxial compression tests. In contrast, the samples made with aluminium flakes present the α phase accompanying the 18R martensitic phase, and do not exhibit the shape memory effect. Both the aluminium flakes flat shape and the higher proportion of aluminium oxide associated with its larger surface area to volume ratio hindered the interdiffusion of the metals, resulting in an aluminium-depleted martensitic phase surrounded by an aluminium oxide-rich layered structure.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42155860","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}
Pub Date : 2023-06-21DOI: 10.1080/00325899.2023.2225284
Hansung Lee, Ashutosh Sharma, Minsu Kim, B. Ahn
ABSTRACT In this study, the effects of Cu addition on AlFeMnTiSi0.75Cu x (x = 0, 0.25, 0.5, 0.75, 1.00; in molar ratios) high entropy alloys (HEAs) prepared via mechanical alloying and spark plasma sintering were investigated. The structure, phase, morphology and composition of HEA powders were analysed and the results revealed that the AlFeMnTiSi0.75Cu x HEAs exhibited a multiphase structure. Additionally, after sintering at 900 °C, the formation of BCC, µ and L21 phases in the densified HEAs was enhanced. The investigation of the hardness, nanoindentation and compressive properties revealed that the microstructural and mechanical properties of AlFeMnTiSi0.75Cu x HEAs were improved at the optimal Cu fraction (0.25 molar ratio). The nanoindentation results revealed that the AlFeMnTiSi0.75Cu x HEAs exhibited the highest hardness and elastic modulus (HIT = 19.2 GPa, EIT = 336 GPa). These results improve the current understanding of multiphase HEAs and may pave way for the development of advanced HEAs with superior mechanical properties.
{"title":"Correlation between the nanomechanical characteristic and the phase transformation of BCC-based high entropy alloys produced via powder metallurgy","authors":"Hansung Lee, Ashutosh Sharma, Minsu Kim, B. Ahn","doi":"10.1080/00325899.2023.2225284","DOIUrl":"https://doi.org/10.1080/00325899.2023.2225284","url":null,"abstract":"ABSTRACT In this study, the effects of Cu addition on AlFeMnTiSi0.75Cu x (x = 0, 0.25, 0.5, 0.75, 1.00; in molar ratios) high entropy alloys (HEAs) prepared via mechanical alloying and spark plasma sintering were investigated. The structure, phase, morphology and composition of HEA powders were analysed and the results revealed that the AlFeMnTiSi0.75Cu x HEAs exhibited a multiphase structure. Additionally, after sintering at 900 °C, the formation of BCC, µ and L21 phases in the densified HEAs was enhanced. The investigation of the hardness, nanoindentation and compressive properties revealed that the microstructural and mechanical properties of AlFeMnTiSi0.75Cu x HEAs were improved at the optimal Cu fraction (0.25 molar ratio). The nanoindentation results revealed that the AlFeMnTiSi0.75Cu x HEAs exhibited the highest hardness and elastic modulus (HIT = 19.2 GPa, EIT = 336 GPa). These results improve the current understanding of multiphase HEAs and may pave way for the development of advanced HEAs with superior mechanical properties.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42611270","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}
Pub Date : 2023-06-20DOI: 10.1080/00325899.2023.2225953
Jiangtao Zhang, Peng Liu
ABSTRACT The powder spreading process is usually performed at preheating temperature in powder-bed-based additive manufacturing (AM). Thus, the powder flowability characterisation at preheating temperature is important for powder spreading processes. However, devices for traditional powder flowability characterising methods are mainly designed for specific conditions at room temperature and cannot consider the effect of temperature on powder flowability. In this work, an experimental platform with a heated rotating drum was set up and a high-speed camera was used to record powder avalanche processes in a heated rotating drum for the powder flowability characterisation at preheating temperature. Nylon and stainless steel powder flowability at different temperatures was assessed by the statistical analysis of avalanche angle, avalanche time, arithmetic mean deviation and surface linearity of powder surface profile. Four parameters provide a good characterisation of powder flowability. The results can provide guidance for the powder flowability characterisation method at preheating temperature in AM.
{"title":"Powder flowability characterisation at preheating temperature in additive manufacturing","authors":"Jiangtao Zhang, Peng Liu","doi":"10.1080/00325899.2023.2225953","DOIUrl":"https://doi.org/10.1080/00325899.2023.2225953","url":null,"abstract":"ABSTRACT The powder spreading process is usually performed at preheating temperature in powder-bed-based additive manufacturing (AM). Thus, the powder flowability characterisation at preheating temperature is important for powder spreading processes. However, devices for traditional powder flowability characterising methods are mainly designed for specific conditions at room temperature and cannot consider the effect of temperature on powder flowability. In this work, an experimental platform with a heated rotating drum was set up and a high-speed camera was used to record powder avalanche processes in a heated rotating drum for the powder flowability characterisation at preheating temperature. Nylon and stainless steel powder flowability at different temperatures was assessed by the statistical analysis of avalanche angle, avalanche time, arithmetic mean deviation and surface linearity of powder surface profile. Four parameters provide a good characterisation of powder flowability. The results can provide guidance for the powder flowability characterisation method at preheating temperature in AM.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47894205","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}
Pub Date : 2023-06-18DOI: 10.1080/00325899.2023.2223794
Y. Chun, Seunghyeok Chung, C. Rhee, H. Ryu
ABSTRACT This work proposes a new neutron absorber, Cu–B composites, with excellent thermal conductivity and good neutron absorbing capability. Mixtures of elemental Cu and B powders with the B contents varying between 10 and 40 at.-% were consolidated into round bars by hot extrusion. The addition of B significantly refined the grain structure, which is related to the suppression of dynamic recrystallisation during hot extrusion and extended recovery during subsequent annealing. Such fine-grained structure in Cu–B composites together with dispersion hardening by B particles contributed to the higher hardness of Cu–B composites. The thermal conductivity of Cu–B composites, being roughly two times higher than that of Al–B4C MMC, decreases with increasing the B contents, which is mainly due to higher volume fraction B particles with lower thermal conductivity, and partly to texture randomisation and refined grain structure in the Cu–B composites.
{"title":"Effects of B addition on microstructure and thermal conductivity of Cu–B composites produced by hot-extrusion of elemental powders","authors":"Y. Chun, Seunghyeok Chung, C. Rhee, H. Ryu","doi":"10.1080/00325899.2023.2223794","DOIUrl":"https://doi.org/10.1080/00325899.2023.2223794","url":null,"abstract":"ABSTRACT This work proposes a new neutron absorber, Cu–B composites, with excellent thermal conductivity and good neutron absorbing capability. Mixtures of elemental Cu and B powders with the B contents varying between 10 and 40 at.-% were consolidated into round bars by hot extrusion. The addition of B significantly refined the grain structure, which is related to the suppression of dynamic recrystallisation during hot extrusion and extended recovery during subsequent annealing. Such fine-grained structure in Cu–B composites together with dispersion hardening by B particles contributed to the higher hardness of Cu–B composites. The thermal conductivity of Cu–B composites, being roughly two times higher than that of Al–B4C MMC, decreases with increasing the B contents, which is mainly due to higher volume fraction B particles with lower thermal conductivity, and partly to texture randomisation and refined grain structure in the Cu–B composites.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43243424","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}
Pub Date : 2023-06-16DOI: 10.1080/00325899.2023.2223019
S. Dewangan, C. Nagarjuna, Hansung Lee, Ashutosh Sharma, B. Ahn
ABSTRACT A preliminary study has been performed to understand the effect of pressureless sintering on the surface morphology of the AlFeCoNi alloy by the addition of the Si element. This study aims to determine the possibility of achieving the densification of high entropy alloy using the conventional sintering technique. The results indicate that the HEAs have a single-phase BCC structure even with the addition of Si. The thermodynamic simulation (CALPHAD) was used to predict the phase formation. The variation of crystallite sizes and lattice strains caused by sintering temperatures was also discussed. In addition, densification mechanisms occurring with the different sintering temperatures have been discussed. The formation of porosity was observed, however, the density of HEAs improved with increasing sintering temperature. Ultimately, it was suggested that the present HEAs required higher sintering temperatures and a longer time to achieve high density.
{"title":"Surface morphology transformation and densification behaviour of conventionally sintered AlFeCoNiSi high entropy alloys","authors":"S. Dewangan, C. Nagarjuna, Hansung Lee, Ashutosh Sharma, B. Ahn","doi":"10.1080/00325899.2023.2223019","DOIUrl":"https://doi.org/10.1080/00325899.2023.2223019","url":null,"abstract":"ABSTRACT A preliminary study has been performed to understand the effect of pressureless sintering on the surface morphology of the AlFeCoNi alloy by the addition of the Si element. This study aims to determine the possibility of achieving the densification of high entropy alloy using the conventional sintering technique. The results indicate that the HEAs have a single-phase BCC structure even with the addition of Si. The thermodynamic simulation (CALPHAD) was used to predict the phase formation. The variation of crystallite sizes and lattice strains caused by sintering temperatures was also discussed. In addition, densification mechanisms occurring with the different sintering temperatures have been discussed. The formation of porosity was observed, however, the density of HEAs improved with increasing sintering temperature. Ultimately, it was suggested that the present HEAs required higher sintering temperatures and a longer time to achieve high density.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44395023","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}
Pub Date : 2023-06-15DOI: 10.1080/00325899.2023.2223015
Long Li, Lei Peng, Wei Zhao
ABSTRACT An apparatus was developed to study the effects of operating parameters on liquid spreading and particle size in centrifugal atomisation. Different areas of aluminium spreading on the surface of the rotary disc were observed, in which the diameter of the ‘Plane area’ showed a linear relationship with the rotational speed. The microscopic morphology of the aluminium powder samples was analysed by scanning electron microscopy (SEM). The variation of particle size distribution curve with rotational speed was explored, and the shape of the curve was changed from ‘Single-peak’ to ‘Double-peak’ when the rotating speed increased to a certain value. The effect of the fragmentation mode on the particle size distribution and median diameter was analysed. The variation of the median diameter of the powder with the rotating speed was obtained. The effect of different disc configurations on the particle size was obtained.
{"title":"Effects of process parameters on the spreading morphology of disc surface and aluminium powder produced by centrifugal atomisation","authors":"Long Li, Lei Peng, Wei Zhao","doi":"10.1080/00325899.2023.2223015","DOIUrl":"https://doi.org/10.1080/00325899.2023.2223015","url":null,"abstract":"ABSTRACT An apparatus was developed to study the effects of operating parameters on liquid spreading and particle size in centrifugal atomisation. Different areas of aluminium spreading on the surface of the rotary disc were observed, in which the diameter of the ‘Plane area’ showed a linear relationship with the rotational speed. The microscopic morphology of the aluminium powder samples was analysed by scanning electron microscopy (SEM). The variation of particle size distribution curve with rotational speed was explored, and the shape of the curve was changed from ‘Single-peak’ to ‘Double-peak’ when the rotating speed increased to a certain value. The effect of the fragmentation mode on the particle size distribution and median diameter was analysed. The variation of the median diameter of the powder with the rotating speed was obtained. The effect of different disc configurations on the particle size was obtained.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45574174","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}