激光原位制备多元颗粒增强钛基复合涂层的组织及性能研究  

Microstructure and Properties of Laser In-situ Synthesized Multiple Particles Reinforced Titanium Matrix Composite

作　　者：迟一鸣 余璐涛 钱大虎 王建刚 韩伯群 姚建华 CHI Yiming;YU Lutao;QIAN Dahu;WANG Jiangang;HAN Boqun;YAO Jianhua(Institute of Laser Advanced Manufacturing,Zhejiang University of Technology,Hangzhou 310023,China;School of Mechanical Engineering,Zhejiang University of Technology,Hangzhou 310023,China;Wuhan Huagong Laser Engineering Co.,Ltd.,Wuhan 430070,China;Jiangsu Fengdong Thermal Technology Limited Company,Jiangsu Yancheng 224100,China)

机构地区：[1]浙江工业大学激光先进制造研究院,杭州310023 [2]浙江工业大学.机械工程学院,杭州310023 [3]武汉华工激光工程有限责任公司,武汉430070 [4]江苏丰东热技术有限公司,江苏盐城224100

出　　处：《表面技术》2025年第5期154-166,共13页Surface Technology

基　　金：国家自然科学基金(52205221);浙江省自然科学基金(LY24E050008);浙江省属高校基本科研业务费项目(RF-A2023008);中国博士后科学基金(2023M741445)。

摘　　要：目的针对钛合金硬度低、耐磨性差的问题,在钛合金表面制备钛基复合涂层,以扩展它在高负载耐磨环境下的应用。方法采用激光合金化工艺在钛合金表面原位制备多元颗粒增强钛基复合涂层,研究不同质量分数的B_(4)C与Ni基合金粉末混合后制备的涂层的物相组成、微观组织和耐磨性能。结果当B_(4)C的质量分数为0时,涂层主要由网状Ni-Ti金属间化合物和β-Ti基底组成,加入B_(4)C后的涂层中原位生成了TiB_(2)、TiB、TiC等多元陶瓷颗粒,且随着B_(4)C含量的增加,原位生成的陶瓷强化相含量显著增加。涂层内出现了板条状组织和块状组织,颗粒状第二相数量明显增加。当B_(4)C的质量分数由0增加到20%时,涂层的显微硬度逐渐提高,涂层的平均显微硬度最高提升至1006.7HV0.3,约为基体的2.65倍,涂层的耐磨性能随着B_(4)C含量的增加呈先提高后下降的趋势。当B_(4)C的质量分数为15%时,涂层的耐磨性能最佳,相较于基体提高了约6.3倍。结论原位生成的棒状TiB_(2)为颗粒状TiC提供了有效的异质形核核心,熔池中多元TiB_(2)、TiC可相互依附、相间生长,最终形成颗粒-棒状、颗粒-板条状或颗粒-块状的复合组织,进一步提高了涂层的显微硬度和耐磨性能。Considering the low hardness and poor wear resistance of titanium alloy,a laser surface alloying process was employed to prepare multi-particle reinforced titanium matrix composite coatings on the surface of TC4,by adding different contents of B_(4)C powder to Ni-based alloy powder.Comparative analyses were conducted on the microstructure,phase composition,and wear resistance of these coatings.The formation mechanism of in-situ TiC-TiB_(2) composite structures was also discussed.Ni-based alloy powder was mixed with different mass fractions of B_(4)C powder,and dried for 2 h.The mixed powder was spread evenly on the substrate surface to a thickness of 0.5 mm.The process parameters were optimized as follows:laser power 1400 W,scanning speed 6 mm/s,spot diameter 4.2 mm,and overlap rate of 30%.The experimental process was carried out in a high-purity argon atmosphere protection chamber.The microstructure morphology and cross-sectional morphology of the coatings were observed with a scanning electron microscope(SEM,ZEISS EVO18),and the chemical compositions were analyzed with an attached energy spectrometer(EDS,Nano Xflash Detector 5010).The chemical compositions of TiC-TiB_(2) composite structures were analyzed with an electron probe microanalyser(EPMA,Shimadzu EPMA-8050G).An X-ray diffractometer(XRD,D/max-Ultima Ⅳ)was employed to identify the phase constituents of the coatings.The microhardness was tested by Vickers microhardness tester(HMV-2T)at a load of 300 g and a holding time of 15 s.Wear test was carried out at room temperature with MMQ-02G friction wear tester at a load of 40 N and a speed of 200 r/min.A GCr15 steel ball was chosen as the counter part.After 40 min of wear test,the three-dimensional morphology and two-dimensional profiles of the worn surface were observed with a laser confocal microscope(CLSM,VK-X1000).The microstructure characteristics of worn surface were observed by SEM(ZEISS EVO18).When the content of B_(4)C was 0,the coating was composed of β-Ti matrix and intermetallic compounds such

关 键 词：激光合金化 原位自生 多元颗粒 TiC-TiB_(2)复合组织 耐磨性能 

分 类 号：TG113.12[金属学及工艺—物理冶金]