摘要
采用等离子熔覆技术制备了四种不同铬含量的Fe-Cr-B-C堆焊合金.借助OM,SEM和XRD等分析手段对合金组织和陶瓷相形貌进行分析.结果表明,熔覆层的微观组织由初生奥氏体+共晶组织组成,合金陶瓷相由BC4+Cr2B+M7C3+M23C6+M23(C,B)6组成,硼化物呈层片状、菊花状等形态分布,陶瓷相数量随Cr元素含量的增大而增多.研究了Cr元素含量对熔覆层耐磨粒磨损性能的影响规律,熔覆层的耐磨性随着Cr元素含量的增加而提高,当Cr元素含量达到15.9%时,大量硼化物等陶瓷相弥散分布在基体中,构成良好的耐磨骨架;初生奥氏体组织均匀分布提高硬质相与基体界面的结合强度,因此其熔覆层具有最佳的耐磨性.
Fe-Cr-B-C hardfacing alloys with four different Cr contents were produced by plasma transferred arc weld-surfacing process(PTA).The microstructure and ceramic phases morphology were investigated by means of optical microscopy(OP),scanning electron microscopy(SEM) and X-ray diffraction(XRD).The results showed that the alloys were hypoeutectic with primary austenite dendrites interspersed by eutectic carbides and borides.The hard phases consisted of BC4,Cr2B,M7C3,M23C6,M23(C,B)6.The borides with plate,rosette shape were observed in the alloys.The volume fraction of ceramic phases increased as the Cr content increased.In addition,the effects of Cr content on wear resistance were evaluated.The wear resistance of cladding layer increased with Cr content.When the volume fraction of Cr reached 15.9%,a multitude of ceramic phases distributed dispersely in the matrix which formed excellent wear resistant structure;and the well-distributed primary austenite enhanced bond strength between borides and matrix,as a result,the wear resistance reached optimum value.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2012年第2期61-64,116,共4页
Transactions of The China Welding Institution
基金
辽宁省教育厅重点实验室资助项目(2008S164)
关键词
等离子熔覆
陶瓷相
组织
耐磨性
plasma arc surfacing
ceramic phases
microstructure
wear resistance
