摘要
以Ti、Al、h-BN粉末混合物为原料,采用激光熔覆技术在TC21表面原位合成出以金属间化合物Ti3Al为熔覆层基体以及以TiB、TiB2、TiN为增强相的复合涂层。对涂层的组织、硬度及摩擦磨损性能进行研究。结果表明:复合涂层与基体呈完全冶金结合,组织均匀致密,增强相主要包括枝晶状TiN、块状TiB2及细针状TiB,其形貌与凝固过程的热力学、动力学以及晶体结构有关。在一定范围内,随着BN含量的增加,涂层中原位合成增强相的体积分数增加,硬度和耐磨性也随之提高。其中,添加8wt%BN复合涂层的性能最优,最高显微硬度为996HV,约为基体的3倍,耐磨性约为基体的7倍。
Taking the powder mixture of Ti,Al and h-BN as raw material,the composite coating on TC21 surface taking in-situ synthesized intermetallic compound Ti3Al as the cladding layer matrix and ceramic TiB,TiB2 and TiN as reinforced phase were prepared by using laser cladding technique.The microstructure,hardness and tribological properties of the coating were studied.The results show that the composite coating and the substrate are completely metallurgical bonding,and its microstructure is uniform and dense.The enhancement phases mainly include dendritic TiN,massive TiB2 and fine needle-like TiB,and its morphology is related to the thermodynamics,kinetics of the solidification process and crystal structure.In some extend,with the increase of BN content,the volume fraction of the in-situ synthesized enhanced phase in the coating increases, and the hardness and abrasion resistance increase.Among them,the performance of the composite coating with the addition of 8wt%BN is optimal,and the maximum microhardness is 996 HV,which is about 3 times of the substrate,the wear resistance is about 7 times of the substrate.
作者
位超群
孙琳
隋欣梦
陈卓
张维平
WEI Chaoqun;SUN Lin;SUI Xinmeng;CHEN Zhuo;ZHANG Weiping(School of Materials Science and Engineering,Dalian University of Technology,Dalian 116023,China)
出处
《热加工工艺》
北大核心
2019年第16期111-115,共5页
Hot Working Technology
基金
国家自然科学基金资助项目(51577021)
航空工业集团公司产学研项目(cxy2103DLLG34)
关键词
激光熔覆
原位合成
复合涂层
显微组织
耐磨性
laser cladding
in- situ synthesis
composite coating
microstructure
wear resistance
