合金化组元(Al,Cr,Si,Ti)含量对激光沉积(FeNiCo)-(AlCrSiTi)非等原子比多组元合金涂层组织与力学性能的影响

Effect of alloying components(Al,Cr,Si,Ti)content on microstructure and mechanical properties of non-equiatomic(FeNiCo)-(AlCrSiTi)multicomponent alloy coatings manufactured by laser deposition

采用激光沉积制备不同含量合金化组元(Al,Cr,Si,Ti)的(FeNiCo)-(AlCrSiTi)多组元合金涂层,研究合金化组元含量对涂层组织与力学性能的影响。结果表明:随着合金化组元(Al,Cr,Si,Ti)含量的增加,涂层中面心立方(FCC)相含量逐渐降低,由FCC相+体心立方(BCC)相的双相结构转变为以BCC相为主的结构,且BCC相内纳米析出相颗粒密度显著增加,颗粒平均尺寸由97 nm降低至36 nm;同时,随着合金化组元含量的增加,涂层中等轴晶组织区域面积增大,等轴晶显著细化,平均晶粒尺寸最小仅为10.8μm;涂层截面平均显微硬度由271HV 0.1上升至718HV 0.1,但涂层抗弯强度由2208 MPa降低至1374 MPa,所能承受的最大弯曲应变也由7.3%降低至0.47%。

(FeNiCo)-(AlCrSiTi)multicomponent alloy coatings with different contents of alloying components(Al,Cr,Si,Ti)were manufactured by laser deposition.The effect of the alloying components content on the microstructure and mechanical properties of the coatings was investigated.The results show that the content of face-centered cubic(FCC)phase in the coatings decreases gradually and the microstructure is changed from FCC phase+body-centered cubic(BCC)phase to BCC phase dominated with the increase of alloying components(Al,Cr,Si,Ti)content.Moreover,the density of nano-precipitation particles in the BCC phase increases significantly and the average size of the nano-precipitation particles decreases from 97 nm to 36 nm.Meanwhile,with the increase of alloying components content,the area of equiaxed grain microstructure in the coatings increases and the equiaxed grains become much finer,with the minimum average grain size of only 10.8μm.Furthermore,the microhardness of the coating cross section increases from 271HV 0.1 to 718HV 0.1.However,the bending strength of the coating decreases from 2208 MPa to 1374 MPa and the maximum bending strain also decreases from 7.3%to 0.47%.