CAJ | 학술논문

在奥氏体钢表面制备具有超细晶结构且能与基体互锁的Ni?Al?WC涂层。首先采用激光在奥氏体钢表面熔覆Ni?Al涂层，然后采用搅拌摩擦加工(FSP)方法，以WC?Co合金为搅拌头，对激光涂层进行大变形改性，形成Ni?Al?WC超细晶复合涂层。采用扫描电子显微镜、X光能量散射谱仪、X射线多晶衍射、硬度仪及摩擦磨损试验机对样品的显微组织、相组成、硬度及摩擦磨损性能进行表征。结果表明，FSP 的大变形效应可形成晶粒尺寸为1~2μm、厚度为100μm的超细晶层。同时，FSP过程还可往变形层中引入WC颗粒，因此变形以及WC颗粒双重强化极大地提高了硬度和耐磨性。另外，FSP大变形使涂层和基体之间形成互锁结构，有利于二者的结合。
재오씨체강표면제비구유초세정결구차능여기체호쇄적Ni?Al?WC도층。수선채용격광재오씨체강표면용복Ni?Al도층，연후채용교반마찰가공(FSP)방법，이WC?Co합금위교반두，대격광도층진행대변형개성，형성Ni?Al?WC초세정복합도층。채용소묘전자현미경、X광능량산사보의、X사선다정연사、경도의급마찰마손시험궤대양품적현미조직、상조성、경도급마찰마손성능진행표정。결과표명，FSP 적대변형효응가형성정립척촌위1~2μm、후도위100μm적초세정층。동시，FSP과정환가왕변형층중인입WC과립，인차변형이급WC과립쌍중강화겁대지제고료경도화내마성。령외，FSP대변형사도층화기체지간형성호쇄결구，유리우이자적결합。
The ultra-fine structured Ni?Al?WC layer with interlocking bonding was fabricated on austenitic stainless steel by combination of laser clad and friction stir processing (FSP). Laser was initially applied to Ni?Al elemental powder preplaced on the austenitic stainless steel substrate to produce a coating for further processing. The as-received coating was subjected to FSP treatment, processed by a rotary tool rod made of WC?Co alloy, to obtain sample for inspection. Microstructure, phase constitutions, hardness and wear property were investigated by methods of scanning electronic microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX) microanalysis, and X-ray diffraction (XRD), hardness test alongside with dry sliding wear test. The results show that the severe deformation effect exerted on the specimen resulted in an ultra-fine grain layer of about 100μmin thickness and grain size of 1?2μm. Synergy between introduction of WC particles to the deformation layer and deformation strengthening contributes greatly to the increase in hardness and friction resistance. An interlocking bonding between the coating and matrix which significantly improves bonding strength was formed due to the severe deformation effect.