Pub Date : 2022-11-02DOI: 10.1080/00325899.2022.2141095
Yang Zhou, Fang Yang, Cun-guang Chen, Zhimeng Guo
ABSTRACT High oxygen Ti6Al4V alloys are fabricated by vacuum sintering and hot rolling using hydrogenation-dehydrogenation Ti6Al4V powder and ZrO2 powder as raw materials. The complete dissolution of oxygen and zirconium atoms results in an increase in lattice constant and strength. As-rolled Ti64-ZrO2 sample exhibits a bimodal structure with a fine acicular α phase of around 1 μm. Ti64-0.75 ZrO2 alloy with equivalent oxygen content close to 0.6 wt.-% presents a good combination of the high tensile strength (1180.2 MPa) and sufficient elongation (7.3%). Therefore, the critical oxygen content for the ductile-to-brittle transition of powder metallurgy Ti6Al4V alloy can be improved by suitable preparation methods. The formation of a fine β transformation structure may be one of the reasons for maintaining sufficient ductility.
{"title":"Microstructure evolution and mechanical property of powder metallurgy Ti6Al4V alloy with high oxygen concentrations","authors":"Yang Zhou, Fang Yang, Cun-guang Chen, Zhimeng Guo","doi":"10.1080/00325899.2022.2141095","DOIUrl":"https://doi.org/10.1080/00325899.2022.2141095","url":null,"abstract":"ABSTRACT High oxygen Ti6Al4V alloys are fabricated by vacuum sintering and hot rolling using hydrogenation-dehydrogenation Ti6Al4V powder and ZrO2 powder as raw materials. The complete dissolution of oxygen and zirconium atoms results in an increase in lattice constant and strength. As-rolled Ti64-ZrO2 sample exhibits a bimodal structure with a fine acicular α phase of around 1 μm. Ti64-0.75 ZrO2 alloy with equivalent oxygen content close to 0.6 wt.-% presents a good combination of the high tensile strength (1180.2 MPa) and sufficient elongation (7.3%). Therefore, the critical oxygen content for the ductile-to-brittle transition of powder metallurgy Ti6Al4V alloy can be improved by suitable preparation methods. The formation of a fine β transformation structure may be one of the reasons for maintaining sufficient ductility.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49307137","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 : 2022-10-28DOI: 10.1080/00325899.2022.2138171
P. Scholzen, A. Rajaei, J. Brimmers, B. Hallstedt, T. Bergs, C. Broeckmann
ABSTRACT The powder metallurgical manufacturing of gears offers a promising opportunity in terms of reducing the noise emission and increasing the power density. Sintered gears weigh less than conventional gears and potentially have a better noise-vibration-harshness behaviour, due to the remaining porosity. However, the potential of sintered gears for highly loaded applications is not fully utilised yet. Six variants of surface densified and case-hardened sintered gears from Astaloy Mo85 are tested to analyse the impact of the densification and case hardening depths on both the tooth root and flank load bearing capacities. Experimental investigations including metallography and computer tomography are carried out to characterise the microstructure. Furthermore, a simulation model is developed to quantitatively describe the residual stress and hardness profiles after the heat treatment. The load bearing capacity was improved by increasing the densification and case hardening depths, where the effect of the case hardening was identified to be predominant.
{"title":"Influence of heat treatment and densification on the load capacity of sintered gears","authors":"P. Scholzen, A. Rajaei, J. Brimmers, B. Hallstedt, T. Bergs, C. Broeckmann","doi":"10.1080/00325899.2022.2138171","DOIUrl":"https://doi.org/10.1080/00325899.2022.2138171","url":null,"abstract":"ABSTRACT\u0000 The powder metallurgical manufacturing of gears offers a promising opportunity in terms of reducing the noise emission and increasing the power density. Sintered gears weigh less than conventional gears and potentially have a better noise-vibration-harshness behaviour, due to the remaining porosity. However, the potential of sintered gears for highly loaded applications is not fully utilised yet. Six variants of surface densified and case-hardened sintered gears from Astaloy Mo85 are tested to analyse the impact of the densification and case hardening depths on both the tooth root and flank load bearing capacities. Experimental investigations including metallography and computer tomography are carried out to characterise the microstructure. Furthermore, a simulation model is developed to quantitatively describe the residual stress and hardness profiles after the heat treatment. The load bearing capacity was improved by increasing the densification and case hardening depths, where the effect of the case hardening was identified to be predominant.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45263024","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 : 2022-10-18DOI: 10.1080/00325899.2022.2133357
L. Cordova, C. Sithole, Eric Macía Rodríguez, I. Gibson, M. Campos
ABSTRACT In powder bed fusion laser beam (PBF-LB), powder reusability remains key to keeping cost-effectivity as well as sustainability. In this study, highly sensitive Ti6Al4V ELI powder typically used for medical and aerospace applications is studied. Powder properties of new and reused powders after 10 build cycles subjected to variations such as morphology, particle size distribution (PSD), chemical composition and flowability were analysed. The flow rate using Carney flowmeter increased from 6.8 s to 12 s. Oxygen content slightly increased from 0.11% to 0.12%. The dimensional deviations are measured in six builds of eight samples spread through the build plate. The density of the cubes does not show relevant differences in density (from 99.6% to 99.9%), only the last batch exhibits slightly lower density than the previous builds. Studied properties for the powder and builds are maintained throughout the experiment, demonstrating repeatability of industrial production of metal parts.
{"title":"Impact of powder reusability on batch repeatability of Ti6Al4V ELI for PBF-LB industrial production","authors":"L. Cordova, C. Sithole, Eric Macía Rodríguez, I. Gibson, M. Campos","doi":"10.1080/00325899.2022.2133357","DOIUrl":"https://doi.org/10.1080/00325899.2022.2133357","url":null,"abstract":"ABSTRACT In powder bed fusion laser beam (PBF-LB), powder reusability remains key to keeping cost-effectivity as well as sustainability. In this study, highly sensitive Ti6Al4V ELI powder typically used for medical and aerospace applications is studied. Powder properties of new and reused powders after 10 build cycles subjected to variations such as morphology, particle size distribution (PSD), chemical composition and flowability were analysed. The flow rate using Carney flowmeter increased from 6.8 s to 12 s. Oxygen content slightly increased from 0.11% to 0.12%. The dimensional deviations are measured in six builds of eight samples spread through the build plate. The density of the cubes does not show relevant differences in density (from 99.6% to 99.9%), only the last batch exhibits slightly lower density than the previous builds. Studied properties for the powder and builds are maintained throughout the experiment, demonstrating repeatability of industrial production of metal parts.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42916621","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 : 2022-10-17DOI: 10.1080/00325899.2022.2134083
W. Hearn, P. Harlin, E. Hryha
ABSTRACT This study focuses on process development and mechanical property evaluation of AISI 4140, 4340 and 8620 low-alloy steel produced by powder bed fusion – laser beam (PBF-LB). Process development found that increasing the build plate preheating temperature to 180°C improved processability, as it mitigated lack of fusion and cold cracking defects. Subsequent mechanical testing found that the low-alloy steels achieved a high ultimate tensile strength (4140:∼1400 MPa, 4340:∼1500 MPa, 8620:∼1100 MPa), impact toughness (4140:∼90–100 J, 4340:∼60–70 J, 8620:∼150–175 J) and elongation (4140:∼14%, 4340:∼14%, 8620:∼14–15%) that met or exceeded the ASTM standards. Mechanical testing also revealed limited directional anisotropy that was attributed to low levels of internal defects (< 0.1%), small grains with weak crystallographic texture and improved tempering due to build plate preheating and post PBF-LB stress relief. This indicates that with adequate process development, low-alloy steels produced by PBF-LB can meet or exceed the performance of conventionally produced alloys.
{"title":"Development of powder bed fusion – laser beam process for AISI 4140, 4340 and 8620 low-alloy steel","authors":"W. Hearn, P. Harlin, E. Hryha","doi":"10.1080/00325899.2022.2134083","DOIUrl":"https://doi.org/10.1080/00325899.2022.2134083","url":null,"abstract":"ABSTRACT This study focuses on process development and mechanical property evaluation of AISI 4140, 4340 and 8620 low-alloy steel produced by powder bed fusion – laser beam (PBF-LB). Process development found that increasing the build plate preheating temperature to 180°C improved processability, as it mitigated lack of fusion and cold cracking defects. Subsequent mechanical testing found that the low-alloy steels achieved a high ultimate tensile strength (4140:∼1400 MPa, 4340:∼1500 MPa, 8620:∼1100 MPa), impact toughness (4140:∼90–100 J, 4340:∼60–70 J, 8620:∼150–175 J) and elongation (4140:∼14%, 4340:∼14%, 8620:∼14–15%) that met or exceeded the ASTM standards. Mechanical testing also revealed limited directional anisotropy that was attributed to low levels of internal defects (< 0.1%), small grains with weak crystallographic texture and improved tempering due to build plate preheating and post PBF-LB stress relief. This indicates that with adequate process development, low-alloy steels produced by PBF-LB can meet or exceed the performance of conventionally produced alloys.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41305555","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 : 2022-08-30DOI: 10.1080/00325899.2022.2116401
G. Bagliuk, S. Kyryliuk
ABSTRACT Comparative results of numerical simulation of the process of hot forging of porous preforms with an axial hole for two deformation schemes are presented: in a die with a flash groove on the inner surface of the forged workpiece cavity and in a closed die. A significant difference in the nature of the evolution of the distribution of deformations and density over the cross-section of the workpiece for the two considered schemes is noted. It is shown that forging in a die with an open volume provides significantly higher degrees of material deformation during forging compared to closed forging, which should lead to an increase in the quality of the structure and final properties of the forged material.
{"title":"Finite element simulation of different deformation modes for powder hot forging","authors":"G. Bagliuk, S. Kyryliuk","doi":"10.1080/00325899.2022.2116401","DOIUrl":"https://doi.org/10.1080/00325899.2022.2116401","url":null,"abstract":"ABSTRACT Comparative results of numerical simulation of the process of hot forging of porous preforms with an axial hole for two deformation schemes are presented: in a die with a flash groove on the inner surface of the forged workpiece cavity and in a closed die. A significant difference in the nature of the evolution of the distribution of deformations and density over the cross-section of the workpiece for the two considered schemes is noted. It is shown that forging in a die with an open volume provides significantly higher degrees of material deformation during forging compared to closed forging, which should lead to an increase in the quality of the structure and final properties of the forged material.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47386876","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}
ABSTRACT Powder bed fusion laser beam, as one of the most promising forming technologies, offers unmatched benefits over traditional processing, particularly in the production of Ti–6Al–4V. The influence of laser line energy density (LLED) on the forming surface, phase composition, micro-hardness, tensile characteristics and wear resistance of Ti–6Al–4V alloy were explored to disclose the evolution of mechanical and tribological properties. According to the findings, the LLED causes ‘depressions’ and ‘highlands’ between nearby scanning tracks. The phase composition did not alter appreciably as LLED increased. Micro-hardness and tensile characteristics increased initially, then declined, and the value of maximum micro-hardness and ultimate tensile strength were 388.17 HV0.2 and 1197.5 MPa, respectively. Furthermore, when the LLED is 0.24 J mm–1, the wear resistance is optimal under the aviation lubricant medium, with an average friction coefficient of 0.1505 and volume wear rate of 6.95∗10−8 mm2∗N−1, and a wear mechanism of mild furrow wear and adhesion wear.
{"title":"Study of mechanical and tribological properties of Ti–6Al–4V alloy fabricated by powder bed fusion laser beam","authors":"Xiaojie Shi, Peipei Lu, Xiu Ye, Shuai Ren, Yiyao Wang, Zi-hua Xie, Yiqing Ma, Xiaojin Miao, Meiping Wu","doi":"10.1080/00325899.2022.2116405","DOIUrl":"https://doi.org/10.1080/00325899.2022.2116405","url":null,"abstract":"ABSTRACT Powder bed fusion laser beam, as one of the most promising forming technologies, offers unmatched benefits over traditional processing, particularly in the production of Ti–6Al–4V. The influence of laser line energy density (LLED) on the forming surface, phase composition, micro-hardness, tensile characteristics and wear resistance of Ti–6Al–4V alloy were explored to disclose the evolution of mechanical and tribological properties. According to the findings, the LLED causes ‘depressions’ and ‘highlands’ between nearby scanning tracks. The phase composition did not alter appreciably as LLED increased. Micro-hardness and tensile characteristics increased initially, then declined, and the value of maximum micro-hardness and ultimate tensile strength were 388.17 HV0.2 and 1197.5 MPa, respectively. Furthermore, when the LLED is 0.24 J mm–1, the wear resistance is optimal under the aviation lubricant medium, with an average friction coefficient of 0.1505 and volume wear rate of 6.95∗10−8 mm2∗N−1, and a wear mechanism of mild furrow wear and adhesion wear.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49281926","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 : 2022-08-25DOI: 10.1080/00325899.2022.2115758
Xin Yang, Chenhao Sun, Fenghui Wang, Yang-lan Lai, S. Liu, Yingkang Wei, J. Yang, Hui-ping Tang
ABSTRACT The inconsistency of high material cost and powder properties are the primary barriers to widespread adoption of metal additive manufacturing. Obviously, powder reuse without affecting the properties of the parts can reduce the cost burden. In this study, the properties of H13 (4Cr5MoSiV1) powder were evaluated 16 build cycles in selective electron beam melting. Results show that the crystal plane spacing and particle size of the powder increased with reuse. With the increase i reuse times, more irregular particles appeared and the flowability decreased. The oxygen and nitrogen content of powder gradually increases from 149 to 250 ppm and 237 ppm to 394 ppm, respectively, with reuse. The simulation results show that the wider particle size distribution, the better the relative packing performance of the powder layer. Powder reuse has no negative effect on the hardness of the as-built samples.
{"title":"Effect of reuse times on H13 powder properties processed by selective electron beam melting","authors":"Xin Yang, Chenhao Sun, Fenghui Wang, Yang-lan Lai, S. Liu, Yingkang Wei, J. Yang, Hui-ping Tang","doi":"10.1080/00325899.2022.2115758","DOIUrl":"https://doi.org/10.1080/00325899.2022.2115758","url":null,"abstract":"ABSTRACT The inconsistency of high material cost and powder properties are the primary barriers to widespread adoption of metal additive manufacturing. Obviously, powder reuse without affecting the properties of the parts can reduce the cost burden. In this study, the properties of H13 (4Cr5MoSiV1) powder were evaluated 16 build cycles in selective electron beam melting. Results show that the crystal plane spacing and particle size of the powder increased with reuse. With the increase i reuse times, more irregular particles appeared and the flowability decreased. The oxygen and nitrogen content of powder gradually increases from 149 to 250 ppm and 237 ppm to 394 ppm, respectively, with reuse. The simulation results show that the wider particle size distribution, the better the relative packing performance of the powder layer. Powder reuse has no negative effect on the hardness of the as-built samples.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46089485","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 : 2022-07-22DOI: 10.1080/00325899.2022.2102839
Mahdi Mirzaaghaei, F. Qods, H. Arabi, M. Milani, B. Mohammad Sadeghi, M. Nourbakhsh
ABSTRACT The goal of this study was to investigate the mechanical properties and microstructure of Ti-15% Mo alloy fabricated using the mechanical alloying and spark plasma sintering (MA-SPS) method. Accordingly, Ti and Mo powders were milled for different times, including 5, 15, 25, 35, and 45 h, and the SPS technique for sintering under a pressure of 25 MPa at 1100°C was used. The X-ray diffraction (XRD) analysis, optical and electron microscopy (SEM), hardness measurements, and compression testing were used to study the phases formed, the morphology of powders, microstructure, and mechanical properties of the as-prepared samples, respectively. The results revealed that owing to increasing the mechanical milling time, the percentage of the beta phase formed was higher, and in addition, it influenced the microstructure and mechanical properties of the samples fabricated after the sintering process. GRAPHICAL ABSTRACT
{"title":"Investigation of mechanical properties and microstructure of Ti-15% Mo alloy produced by mechanical alloying and sintering with SPS (MA-SPS)","authors":"Mahdi Mirzaaghaei, F. Qods, H. Arabi, M. Milani, B. Mohammad Sadeghi, M. Nourbakhsh","doi":"10.1080/00325899.2022.2102839","DOIUrl":"https://doi.org/10.1080/00325899.2022.2102839","url":null,"abstract":"ABSTRACT The goal of this study was to investigate the mechanical properties and microstructure of Ti-15% Mo alloy fabricated using the mechanical alloying and spark plasma sintering (MA-SPS) method. Accordingly, Ti and Mo powders were milled for different times, including 5, 15, 25, 35, and 45 h, and the SPS technique for sintering under a pressure of 25 MPa at 1100°C was used. The X-ray diffraction (XRD) analysis, optical and electron microscopy (SEM), hardness measurements, and compression testing were used to study the phases formed, the morphology of powders, microstructure, and mechanical properties of the as-prepared samples, respectively. The results revealed that owing to increasing the mechanical milling time, the percentage of the beta phase formed was higher, and in addition, it influenced the microstructure and mechanical properties of the samples fabricated after the sintering process. GRAPHICAL ABSTRACT","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42151702","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 : 2022-07-19DOI: 10.1080/00325899.2022.2099636
Christian Berger, J. Pötschke, M. Fries, T. Moritz, A. Michaelis
ABSTRACT Additive Manufacturing is experiencing an upswing in many sectors of industry for a broad variety of materials. Processes are mainly developed for polymers and metals. For ceramics, hardmetals and especially cermets there are only a few additive processes suitable. The powder-based technique Binder-Jetting is one of these suitable processes with high productivity and relatively low green density. Within this study, TiCN-based cermets are printed by Binder-Jetting for the first time. The complexity of influences of the morphology and composition of cermet powders are discussed in regard to bulk density and material properties of printed and sintered parts. Studied TiCN-based cermet compositions represent different Ni and Mo2C contents. Main points of this investigation are further the adjustment of ratio of the raw materials for good sintering behaviour and their influence on the microstructures and as a function of varied sintering temperatures.
{"title":"Binder-jetting of TiCN-based cermets","authors":"Christian Berger, J. Pötschke, M. Fries, T. Moritz, A. Michaelis","doi":"10.1080/00325899.2022.2099636","DOIUrl":"https://doi.org/10.1080/00325899.2022.2099636","url":null,"abstract":"ABSTRACT Additive Manufacturing is experiencing an upswing in many sectors of industry for a broad variety of materials. Processes are mainly developed for polymers and metals. For ceramics, hardmetals and especially cermets there are only a few additive processes suitable. The powder-based technique Binder-Jetting is one of these suitable processes with high productivity and relatively low green density. Within this study, TiCN-based cermets are printed by Binder-Jetting for the first time. The complexity of influences of the morphology and composition of cermet powders are discussed in regard to bulk density and material properties of printed and sintered parts. Studied TiCN-based cermet compositions represent different Ni and Mo2C contents. Main points of this investigation are further the adjustment of ratio of the raw materials for good sintering behaviour and their influence on the microstructures and as a function of varied sintering temperatures.","PeriodicalId":20392,"journal":{"name":"Powder Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48883365","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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