Laser powder bed fusion of NiTiFe shape memory alloy via premixed powder:microstructural evolution,mechanical and functional properties  

作　　者：Bo Yuan Jin-Guo Ge Liang Zhang Hong-Jun Chen Long-Sha Wei Yu-Duo Zhou Run-Hua Song 

机构地区：[1]Institute of Intelligent Manufacturing Technology,Shenzhen Polytechnic,Shenzhen 518055,China [2]School of Mechanical and Electrical Engineering,Guilin University of Electronic Technology,Guilin 541004,China [3]Guangdong Advanced Polymer Composite Engineering Technology Research Center,Shenzhen Academy of Aerospace Technology,Shenzhen 518057,China [4]Jihua Laboratory Testing Center,Jihua Laboratory,Foshan 528000,China

出　　处：《Rare Metals》2024年第5期2300-2316,共17页稀有金属（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.52201225);the Post-doctoral Foundation Project of Shenzhen Polytechnic(No.6021330013K0);the Additive Manufacturing Technology R&D Center(No.602331004PQ);Guangdong Provincial General University Innovation Team Project(No.2020KCXTD047);Shenzhen ScienceandTechnologyInnovationCommission(No.JSGG20200701095008016);Shenzhen Science and Technology Program(No.RCBS20221008093241051);the Natural Science Foundation of Guangdong Province(No.2022A1515110389)。

摘　　要：High-cost pre-alloyed powder is the bottleneck problem that limits the widespread application of additivemanufactured shape memory alloys.In this work,the lowcost ternary NiTiFe shape memory alloy is fabricated by laser powder bed fusion(LPBF)technique via mechanically mixed pre-alloy NiTi powder and varying contents pure Fe powder(1,2,3 wt%).All NiTiFe alloys show a relative density of up to 99.8%by optimizing the LPBF processing parameters.Owing to the heterogeneous nucleation effect of micron-sized Fe particles,both grain refinement and texture weakening are generated in the NiTiFe alloys,accompanied by the reduction of dislocation density.For the room-temperature mechanical properties,the NiTi-3Fe alloy shows the highest microhardness of HV370,but the fracture strength and elongation reduce to1701 MPa and 23%simultaneously.The evolution of mechanical properties is attributed to the high internal defects,low dislocation density and the incoherent oxide.Moreover,the NiTi-3Fe alloy shows the quasi-linear superelasticity behavior;the superelastic recoverable strain of NiTi-1Fe and NiTi-2Fe decreased with the increase in Fe content.This study provided a new-fangled insight for the development of multi-component NiTi-based shape memory alloys by additive manufacturing.

关 键 词：Additive manufacturing Shape memory alloy Metal matrix composite MICROSTRUCTURE Mechanical properties 

分 类 号：TG665[金属学及工艺—金属切削加工及机床] TG139.6[一般工业技术—材料科学与工程]