Mo-Ni-B系三元硼化物制备与性能研究评述  

Research Review of Mo-Ni-B Ternary Boride Preparation and Properties

作　　者：胡肇炜[1] 李文戈[1] 

机构地区：[1]上海海事大学,上海201306

出　　处：《表面技术》2016年第11期1-9,共9页Surface Technology

基　　金：国家自然科学基金(51172140;51572168);上海市教委科研创新项目(11ZZ141)~~

摘　　要：Mo-Ni-B三元硼化物具有优良的力学性能和耐磨耐蚀性能。反应烧结法是最常见的制备方法。单纯添加不同元素(如Cr、V、Mn)或同时添加这些元素以及改变Mo/B原子比,会对陶瓷的力学性能(抗弯强度、硬度)、微观组织(平均粒径、收缩率、形成晶系)、耐磨耐蚀性能产生影响。Mo_2NiB_2在烧结过程中会因烧结温度和添加的元素等形成四方晶M_3B_2、M_5B_3以及斜方晶M_3B_2、M_5B_3等,这些物相与最终的性能密切相关。添加V或Cr会提高抗弯强度和硬度,促使斜方晶体M_3B_2向四方晶M_3B_2转变。添加Mn会细化Mo_2NiB_2晶粒,提高力学性能。M5B3只有在添加了其他元素后才会出现,并且与添加元素的含量、热处理及Mo/B比有关。烧结法制备的Mo_2NiB_2最高抗弯强度可达3.25 GPa,硬度可达89.6HRA。烧结法制备的陶瓷涂层在具体应用时需再次进行烧结才可与基体结合。而激光熔覆反应法及其他喷涂法可以在基体上直接形成陶瓷涂层。激光熔覆反应法可以制备耐蚀性超过304SS不锈钢的复合陶瓷涂层,硬度可达1100HV以上,制备工艺如激光工艺参数(激光功率、扫描速度)、粉末体系(原子比、添加元素)对涂层性能有很大的影响。激光功率为2500 W、扫描速度1.5 mm/s、Mo/B比为1时可获得性能优良的Mo_2NiB_2涂层。Mo-Ni-B ternary boride is of good mechanical property, wear-resistance and corrosion resistance and reaction sintering method is a common preparation method. Adding such elements as Cr, V, Mn repectively or jointly and changing Mo/B atomic ratio had different effects on properties of ternary boride including mechanical properties（transverse rupture strength, hardness）, microstructure（mean grain size, shrinkage factor, crystal system formation）, wear resistance and corrosion resistance. Tetragonal M3B2, M5B3 and orthorhombic M3B2, M5B3 were generated by Mo2NiB2 due to sintering temperature andelement addition during sintering. These phases were closely related to the final properties. Bending strength and hardness would be improved by adding V or Cr, causing a structural transition of Mo2NiB2 from orthorhombic to tetragonal structure. Mo2NiB2 grains were refined and mechanical properties were improved by adding Mn. M5B3 only appeared under the effects of content, heat treatment and Mo/B ratio of the added elements after other elements were added. For the Mo2NiB2 prepared by sintering method, its maximum bending strength was up to 2.25 GPa and maximum hardness was 89.6HRA. The ceramic coating prepared by sintering method should be combined with the substrate after repeated sintering for specific application. However, laser cladding reaction method and other spray methods could form ceramic coating on the substrate directly. The laser cladding reaction method could be used to prepare composite ceramic coating with corrosion resistance higher than that of 304 SS stainless steel and hardness of more than 1100 HV. The coating’s properties were greatly affected by preparation technology such as laser technological parameter（laser power and scanning speed）, powder system（atomic ratio and added elements）. A fine Mo2 NiB 2 coating is obtained when laser power is 2500 W, scanning speed is 1.5 mm/s and Mo/B atomic ratio is 1.

关 键 词：Mo-Ni-B 三元硼化物 制备方法 力学性能 微观组织 耐磨性 耐蚀性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]