La_(2)O_(3)掺杂铁基记忆合金涂层组织与性能研究  

Microstructure and properties of La_(2)O_(3)doped Fe-based shape memory alloy coating

作　　者：徐娜 庞驰[1] 徐鹏[1] 王卫 荆志杰 XU Na;PANG Chi;XU Peng;WANG Wei;JING Zhijie(College of Materials and Metallurgy,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州大学材料与冶金学院,贵阳550025

出　　处：《激光技术》2024年第3期387-394,共8页Laser Technology

基　　金：贵州省科技计划资助项目(黔科合基础-ZK[2021]一般241)。

摘　　要：为了探究La_(2)O_(3)对激光熔覆形状记忆合金涂层组织和性能的影响,采用宽带激光熔覆技术在42CrMo中碳钢表面制备了掺杂La_(2)O_(3)的Fe17Mn5Si10Cr5Ni形状记忆合金复合涂层,通过表征得到了La_(2)O_(3)对复合涂层的显微组织、维氏硬度、耐磨性、耐蚀性和表面残余应力的影响结果。结果表明,La_(2)O_(3)显著降低了晶粒尺寸,掺杂质量分数w=0.009时,晶粒尺寸达到最小值3.03μm,而复合涂层具有最大硬度454.7 HV 0.2,磨损量最低;并得到最低的自腐蚀电流为4.287×10^(-7)A/cm^(2),最高的自腐蚀电位为-0.843 V,涂层保护率达到94.83%,La_(2)O_(3)明显提高了涂层的耐腐蚀性能;此时涂层的残余应力由拉应力转变为压应力,并在Fe-Mn-Si/La_(2)O_(3)产生的最大残余压应力值为-378 MPa。此项研究为低应力高性能激光熔覆涂层的开发和推广提供了实践参考。To investigate the effect of La_(2)O_(3)on the organization and properties of laser melting shape memory alloy coatings,a broadband laser melting technique was used to prepare a La_(2)O_(3)-doped Fe17Mn5Si10Cr5Ni shape memory alloy composite coating on the surface of 42CrMo medium carbon steel.The results of the effect of La_(2)O_(3)on the microstructure,Vickers hardness,wear resistance,corrosion resistance and surface residual stress of the composite coatings were obtained by characterization.The results show that La_(2)O_(3)significantly reduces the grain size,when the doping mass fraction of 0.009 grain size reaches a minimum value of 3.03μm.The composite coating has a maximum hardness of 454.7 HV 0.2 and the lowest wear and the lowest self-corrosion current of 4.287×10^(-7)A/cm^(2)and the highest self-corrosion potential of-0.843 V are obtained,and the coating protection rate reaches 94.83%.La_(2)O_(3)significantly improves the corrosion resistance of the coating.The residual stresses change from tensile to compressive stresses,with the highest residual compressive stress value of-378 MPa at Fe-Mn-Si/La_(2)O_(3).This study provides a practical reference for the development and promotion of low-stress high-performance laser cladding coatings.

关 键 词：激光技术 涂层 激光熔覆 La_(2)O_(3) 形状记忆合金 

分 类 号：TN249[电子电信—物理电子学] TG665[金属学及工艺—金属切削加工及机床] TG142.1[一般工业技术—材料科学与工程]