激光制备Fe-Ni基非晶复合涂层及退火性能分析

Fe-Ni-based amorphous coatings fabricated by laser and annealing performance

采用15 kW快速轴流型CO2激光器在低碳钢基体上制备了非晶复合涂层Fe31Ni31Si18B18Nb2.利用X射线衍射(XRD)和扫描电镜(SEM)分析了涂层的物相、组织结构与加入元素形态对涂层非晶形成能力的影响.结果表明,Nb元素以铌铁的形式加入更加有利于非晶层的形成,铌铁加入后抑制了Ni2Si和Ni2B相的产生,涂层中只出现了γ-(Fe,Ni)和Fe2B两种晶相.在500℃低温退火时,其硬度上升;在600℃退火时,硬度下降;在700和800℃退火时,硬度又升高;在900℃退火时,硬度较800℃有了较大的下降.

FeNi-based amorphous coating was prepared by laser cladding on the mild steel with a 15 kW continuous CO2 laser.The phases,microstructure and the effect of addition elements on forming ability of the amorphous coatings were studied by using X-ray diffractometer and scan electron microscope.The results show that the addition form of the ferroniobium is better than that of the pure niobium powder during the synthesis of the amorphous coating.The addition of ferroniobium can restrain the generation of the crystalline grains such as Ni2Si and Ni2B.The microhardness of the coating increases after annealing at 500 ℃,declines at 600 ℃,increases at 700 ℃ and 800 ℃ and declines at 900 ℃.