摘要
为提高TC4钛合金的耐磨性,利用激光熔覆技术(laser cladding,LC)在TC4钛合金表面制备Ni60+50%WC(体积分数)和deloro22(d22)粉末打底+(Ni60+50%WC)2种耐磨复合涂层。采用扫描电子显微镜(SEM)、能谱仪(EDS)以及X射线衍射仪(XRD)来表征涂层的微观结构和物相组成;使用HV-1000显微维氏硬度计、HRS-2M型高速往复摩擦磨损试验机和WDW-100D电子万能试验机来分析涂层的性能。结果表明:2种涂层均由W_(2)C、TiC、Ni_(17)W_(3)、Ni_(3)Ti和Ti_(x)W_(1-x)相组成,2种涂层不仅与基体呈现出优异的冶金结合,而且组织均匀致密,没有裂纹瑕疵;由于涂层中存在着原位合成的硬质相和细晶强化共同作用使得涂层硬度显著提高,约为TC4基体的2.82倍;2种涂层的摩擦系数(COF)和磨损量都远低于TC4钛合金基体;Ni60+50%WC复合涂层和d22粉末打底+(Ni60+50%WC)复合涂层的抗剪切结合强度分别为188.19和49.11 MPa。2种涂层均能显著改善TC4钛合金基体表面的硬度和耐磨性能,其中Ni60+50%WC复合涂层在硬度、耐磨性和结合强度等方面表现得更出色。
In order to improve the wear resistance of TC4 titanium alloy,two wear-resistant composite coatings of Ni60+50vol%WC and d22 powder based+(Ni60+50%WC)were prepared on the surface of TC4 titanium alloy by laser cladding.Microstructure and phase composition of the coating were characterized by scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and X-ray diffractometer(XRD).The properties of the coating were analyzed by HV-1000 micro Vickers hardness tester,HRS-2M high-speed reciprocating friction and wear tester and WDW-100D electronic universal testing machine.The results show that the two coatings are composed of W_(2)C,TiC,Ni_(17)W_(3),Ni_(3)Ti and Ti_(x)W_(1-x) phases;the two coatings not only exhibit excellent metallurgical bonding with the substrate,but also have uniform and dense microstructure without cracks.Due to the presence of the in-situ synthesized hard phase and fine-grain strengthening,the hardness of the coating is significantly increased,which is about 2.82 times that of the TC4 substrate.The friction coefficient(COF)and wear amount of the two coatings are much lower than that of TC4 titanium alloy substrate.The shear bonding strength of Ni60+50%WC composite coating and d22 powder based+(Ni60+50%WC)composite coating are 188.19 and 49.11 MPa,respectively.Both coatings can significantly improve the hardness and wear resistance of the TC4 titanium alloy substrate surface,and Ni60+50%WC composite coating performs better in hardness,wear resistance and bonding strength.
作者
刘金刚
杨建花
王高升
李毅
郑剑云
Liu Jingang;Yang Jianhua;Wang Gaosheng;Li Yi;Zheng Jianyuan(School of Mechanical Engineering and Mechanics,Xiangtan University,Xiangtan 411105,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2022年第8期2907-2914,共8页
Rare Metal Materials and Engineering
基金
国家自然科学基金(52075465)
湖南省杰出青年基金(2019JJ20015)
湖南省科技创新计划(2020RC4038)
湖南省研究生科研创新项目(CX20200644)
湖南省教育厅资助科研项目(20B131)。
关键词
激光熔覆
钛合金
微观组织
显微硬度
耐磨性
laser cladding
titanium alloy
microstructure
microhardness
wear resistance