陶瓷硬质相对铁基复合材料组织和性能的影响

Effect of ceramic phase on microstructure and mechanical properties of ferrous matrix composite

关键词:  原位合成  明弧堆焊  陶瓷硬质相  铁基复合材料  组织和性能

Key words:  in situ synthesis  open arc surfacing  ceramic particles  iron matrix composites  microstructure and properties

摘要:

采用明弧堆焊技术在Q235基体金属表面制备Fe-Cr-C-B-N-Ti系铁基复合材料. 借助金相显微镜、扫描电子显微镜、X射线衍射仪、洛氏硬度计和磨料磨损试验机对铁基复合材料的组织和性能进行分析与测试. 结果表明，铁基复合材料的基体组织由马氏体（M）和少量残余奥氏体（A）组成，硬质相由TiB₂，TiN，TiC，M₂₃（C，B）₆，M₃（C，B）和M₂B组成. 随着钛添加量的增多，初生陶瓷硬质相颗粒（TiB₂，TiN和TiC）和共晶硬质相（M₂₃（C，B）₆，M₃（C，B）和M₂B）增多，基体组织减少并细化. 当钛添加量为4%时，铁基复合材料的耐磨性达到最佳，此时硬度为66 HRC，磨损量为0.042 9 g.

Abstract:

In order to improve the wear resistance of the material surface, the Fe-Cr-C-B-N-Ti-based iron matrix composite was prepared on the Q235 matrix metal surface by using the bright arc surfacing technology. Metallographic microscope, scanning electron microscope, X ray diffractometer, Rockwell hardness tester and abrasive wear tester were used to analyze and test the microstructure and properties of iron-based composites. The results show that the matrix structure of iron-based composites is composed of martensite (M) and a small amount of retained austenite (A), and the hard phase is composed of TiB₂, TiN, TiC, M₂₃ (C, B)₆, M₃ (C, B) and M₂B. With the increase of titanium addition, the hardness phase particles (TiB ₂, TiN and TiC) and eutectic hard phase (M₂₃ (C, B)₆, M₃ (C, B) and M₂B) increase, and the matrix structure decreases and refine. When the amount of titanium is 4%, the wear resistance of the iron matrix composite is the best, at this time the hardness is 66HRC and the wear amount is 0.042 9 g.