金属表面梯度增强层的制备研究进展

Research Progress on Preparation of Gradient Reinforcement Layers on Metal-Based Surfaces

碳化物增强金属表面复合材料兼具碳化物的高硬度、高模量及基体的高韧性、高塑性优势,是提高金属材料使用寿命的有效途径。但是,随着碳化物颗粒体积分数提高,复合材料强度显著增大的同时韧性却大幅下降。如何改善碳化物/金属复合材料的强韧性倒置问题成为复合材料研究领域基础性难题之一。目前,报道的碳化物/金属基复合材料的表面复合强韧化方式主要有表面梯度化、纳米复合、表面应力以及新型结构等方式。主要讨论了金属表面工程技术的重要性以及表面梯度增强层的研究进展和制备现状,详细探讨了表面梯度增强层的优势,并提出了利用表面处理技术制备金属表面碳化物陶瓷梯度复合层,以期实现零件表面增强体的连续或逐级变化;同时保持基体的良好性能,有望提高金属材料的使役性能,增强表面特性,延长使用寿命,具有重要的工程实际价值。

Carbide reinforced metal matrix surface composites have the advantages of high hardness,high modulus of carbide and the high toughness and high plasticity of the matrix,which is an effective way to improve the service life of metal materials.However,with the increase of carbide particle volume fraction,the strength of the composites increases significantly while the toughness decreases significantly.How to improve the strength and toughness inversion of ceramic/metal composites has become one of the basic problems in the field of composite research.At present,the reported toughening methods of carbide/metal-based surface composites mainly include surface gradient,nanocomposite,surface stress and new structure.The importance of metal surface engineering technology and the research progress and preparation status of surface gradient enhancement layers were discussed.The advantages of the surface gradient reinforcement layer were discussed in detail,and the surface treatment technology was proposed to prepare carbide ceramic gradient composite layer on the metal-based surface,in order to realize the continuous or step-by-step change of the surface reinforcement of the parts,while maintaining the good performance of the matrix,which was expected to improve the service performance of the metal material,enhance the surface characteristics,and prolong the service life.It has important engineering practical value.