钛合金表面激光熔覆陶瓷颗粒增强钛基复合涂层研究进展与展望

Progress and prospects of ceramic particle-reinforced titanium matrix composite coatings by laser cladding on titanium alloy surfaces

摘要:

钛合金凭借低密度、高比强度与优良耐蚀性，在深地钻探装备领域应用潜力巨大，但其硬度偏低、耐磨性能不足、高温易氧化等短板，极大限制了井下工程规模化应用。采用激光熔覆制备陶瓷颗粒增强钛基复合涂层是提升钛合金表面性能的关键改性技术。本文系统梳理激光熔覆改性钛合金的相关研究进展：阐述激光熔覆基本原理与工艺参数对涂层组织及性能的调控规律，对比传统试验设计、智能优化算法两类参数优化方法的优劣与适用工况；梳理陶瓷增强相分类与选材原则，从耐磨、耐蚀、高温抗氧化三个维度归纳钛基复合涂层研究成果；现有研究多仅针对单一性能开展测试，针对深地井下“高温?磨损?腐蚀”多场耦合环境的涂层失效机理研究尚不充分。后续需重点开展熔覆粉末体系智能设计、复合辅助熔覆工艺开发与多场耦合失效机制研究，为深地钻探钛合金钻具延寿设计与服役可靠性评价提供理论依据。

Abstract:

Titanium alloys exhibit great application potential in deep-earth drilling equipment owing to their low density， high specific strength， and excellent corrosion resistance. However， their inherent drawbacks-such as low hardness， insufficient wear resistance， and susceptibility to high-temperature oxidation-severely restrict large-scale engineering applications downhole. Laser cladding of ceramic particle-reinforced titanium matrix composite coatings is a key surface modification technology to enhance the surface performance of titanium alloys. This paper systematically reviews the research progress on laser cladding modification of titanium alloys. The fundamental principles of laser cladding and the governing effects of process parameters on coating microstructure and properties are elucidated， and the advantages， disadvantages， and applicable conditions of two types of parameter optimization methods-traditional experimental design and intelligent optimization algorithms-are compared. Furthermore， the classification and material selection criteria of ceramic reinforcing phases are systematically reviewed， and research achievements on titanium matrix composite coatings are summarized from three dimensions： wear resistance， corrosion resistance， and high-temperature oxidation resistance. Most existing studies have focused only on single performance tests， while research on coating failure mechanisms under the multi-field coupled environment of "high temperature-wear-corrosion" in deep downhole conditions remains insufficient. Future efforts should be directed toward the intelligent design of cladding powder systems， the development of hybrid auxiliary cladding processes， and the investigation of multi-field coupled failure mechanisms， so as to provide a theoretical basis for the life extension design and service reliability evaluation of titanium alloy drilling tools in deep-earth drilling.