表面技术2025，Vol.54Issue(5)：154-166,13.DOI:10.16490/j.cnki.issn.1001-3660.2025.05.012
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 Coating
摘要
Abstract
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 B4C 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-TiB2 composite structures was also discussed. Ni-based alloy powder was mixed with different mass fractions of B4C 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 1 400 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-TiB2 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 B4C was 0,the coating was composed of β-Ti matrix and intermetallic compounds such as NiTi and NiTi2.After adding B4C powder,reinforced phases such as TiB2,TiC and TiB,etc.were in-situ generated in the coatings.With the increase of B4C content,more phases were generated in the coatings,TiC-TiB2 composite structures were formed.In the molten pool,preferential nucleation and precipitation of TiB2,Ti,C and other elements aggregated on the surface of TiB2.Due to the high lattice match between TiC and TiB2,TiC dependant nucleation of TiB2,TiB2 in the molten pool continued to grow on the surface of the precipitated TiB2.The subsequent precipitation of TiB2 occurred in different orientations.Eventually,TiC-TiB2 composite structures in the form of particles-rod,particles-lath,particles-block were formed.The microhardness of the coatings gradually enhanced,with the increase of B4C content.The microhardness of the TA3 coating reached up to 1 006.7HV0.3.The dispersion strengthening of in-situ reinforcements likes TiC,TiB,TiB2,etc.were beneficial to wear resistance.Also,the superior plasticity of Ni-Ti intermetallic compounds contributed to improved fracture toughness.When adding 15%B4C,the coating exhibited the best wear-resistant,which was about 6.3 times higher than that of the substrate.However,with more content of B4C added,the coating composed of coarse microstructures and unevenly distributed reinforcements.Thus,the wear resistance of the coating with 20%B4C was slightly reduced.关键词
激光合金化/原位自生/多元颗粒/TiC-TiB2复合组织/耐磨性能Key words
laser alloying/in-situ synthesis/multiple particle/TiC-TiB2 composite structures/wear-resistant分类
矿业与冶金引用本文复制引用
迟一鸣,余璐涛,钱大虎,王建刚,韩伯群,姚建华..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[J].表面技术,2025,54(5):154-166,13.基金项目
国家自然科学基金(52205221) （52205221）
浙江省自然科学基金(LY24E050008) （LY24E050008）
浙江省属高校基本科研业务费项目(RF-A2023008) （RF-A2023008）
中国博士后科学基金(2023M741445) National Natural Science Foundation of China(52205221) （2023M741445）
Zhejiang Provincial Natural Science Foundation of China(LY24E050008) （LY24E050008）
Fundamental Research Funds for the Provincial Universities of Zhejiang(RF-A2023008) （RF-A2023008）
China Postdoctoral Science Foundation(2023M741445) （2023M741445）
