超硬材料包覆新技术研究综述

Review on the novel technology of coating superhard materials

为了提高超硬材料工具或制品的性能并延长其使用寿命,对超硬材料进行表面包覆,不仅可以明显提高超硬材料与基体的机械结合强度,还具有改善超硬材料耐用性、热稳定性、分散性和抗氧化性能等作用。通常,超硬材料表面包覆的方法主要有化学镀、电镀、真空微蒸发镀、物理气相沉积、化学气相沉积等。采用超硬材料表面包覆新技术,包括熔盐处理、钎焊、溶胶凝胶法、异质外延生长、等离子体烧结、自蔓延烧结、静电纺丝等新技术实现了超硬材料的表面包覆,可以针对特定的使用目的和需求,采用不同的技术在超硬材料表面对组织结构、形貌、物理和化学成分进行复合设计、修饰和性能调控,对相关研究成果进行了综述。

To improve the mechanical strength,performance and prolong the service life of the tools made from superhard materials,it is important to coat these materials,which not only greatly improves the mechanical bonding strength between superhard materials and matrix,but also upgrades the durability,thermal stability,dispersibility and oxidation resistance.The traditional coating approaches are commonly used,such as electroless plating,electroplating,vacuum vapor deposition,physical vapor deposition,chemical vapor deposition...,etc.For specific purposes and demands,some novel coating approaches,like vacuum brazing,microwave-salt molten treatment,sol-gel method,heteroepitaxial growth of crystals,plasma sintering,self propagating sintering and electrospinning are also applied to coat the superhard materials.These different new methods are employed to modify the microstructure,morphology,physical and chemical composition of the superhard materials surface to realize the composite design,modification and performance control.The related research results were reviewed in this paper.