This work systematically studied the effect of volumetric energy density E on the densification,mi-crostructures,tensile mechanical properties,and shape memory performance of a Fe-Mn-Si-Cr-Ni shape memory alloy(SMA)fa...This work systematically studied the effect of volumetric energy density E on the densification,mi-crostructures,tensile mechanical properties,and shape memory performance of a Fe-Mn-Si-Cr-Ni shape memory alloy(SMA)fabricated by laser powder bed fusion(L-PBF).An E of 90-265 J/mm3 is suggested to fabricate the Fe-Mn-Si-Cr-Ni SMA with minor metallurgical defects and a high relative density of above 99%.The increase in E can promote the formation of the primaryγaustenite and the solid phase trans-formation from the primaryδferrite to theγaustenite,which helps to achieve a nearly complete y austenitic microstructure.The increase in E also contributes to fabricating the Fe-Mn-Si-Cr-Ni SMA with superior comprehensive mechanical properties and shape memory performance by L-PBF.The Fe-Mn-Si-Cr-Ni SMA with a combination of good ductility of around 30%,high yield strength of above 480 MPa,an ultrahigh ultimate tensile strength of above 1 GPa,and large recovery strain of about 6%was manu-factured by L-PBF under a high E of 222-250 J/mm^(3).The good shape memory effect,excellent compre-hensive mechanical properties,and low cost of Fe-Mn-Si-Cr-Ni SMAs,as well as the outstanding ability to fabricate complex structures of L-PBF technology,provide a solid foundation for the design and fabri-cation of novel intelligent structures.展开更多
基金supported by the Chinese National Natural Science Fund (No.U1864208)the National Science and Technology Major Project (No.2017-VII-0011-0106)+8 种基金the Youth Science Fund Project of National Natural Science Foundation of China (No.52105396)the Postdoctoral Research Foundation of China (No.2020M682410)Postdoctoral Science and Technology Activity Program of Hubei Province (No.0106110134)the Project Supported by Jiangsu Key Laboratory of 3D Printing Equipment and Manufacturing (No.3DL202104)the Science and Technology Planning Project of Tianjin (No.20ZYJDJC00030)the Key Program of Research and Development of Hebei Province (No.202030507040009)the Fund for Innovative Research Groups of Natural Science Foundation of Hebei Province (No.A2020202002)the Natural Science Foundation of Chongqing (No.cstc2021jcyj-msxmX0241)the Key Project of Natural Science Foundation of Tianjin (No.S20ZDF077).
文摘This work systematically studied the effect of volumetric energy density E on the densification,mi-crostructures,tensile mechanical properties,and shape memory performance of a Fe-Mn-Si-Cr-Ni shape memory alloy(SMA)fabricated by laser powder bed fusion(L-PBF).An E of 90-265 J/mm3 is suggested to fabricate the Fe-Mn-Si-Cr-Ni SMA with minor metallurgical defects and a high relative density of above 99%.The increase in E can promote the formation of the primaryγaustenite and the solid phase trans-formation from the primaryδferrite to theγaustenite,which helps to achieve a nearly complete y austenitic microstructure.The increase in E also contributes to fabricating the Fe-Mn-Si-Cr-Ni SMA with superior comprehensive mechanical properties and shape memory performance by L-PBF.The Fe-Mn-Si-Cr-Ni SMA with a combination of good ductility of around 30%,high yield strength of above 480 MPa,an ultrahigh ultimate tensile strength of above 1 GPa,and large recovery strain of about 6%was manu-factured by L-PBF under a high E of 222-250 J/mm^(3).The good shape memory effect,excellent compre-hensive mechanical properties,and low cost of Fe-Mn-Si-Cr-Ni SMAs,as well as the outstanding ability to fabricate complex structures of L-PBF technology,provide a solid foundation for the design and fabri-cation of novel intelligent structures.