Ti(C,N)基金属陶瓷因具有高强度、高硬度、耐高温、耐酸碱、耐磨损等优良性能而被广泛应用于刀具、模具等.在高温切削加工时,金属陶瓷刀具不但具有优良的抗粘附性和热稳定性,还拥有比硬质合金刀具更好的高温红硬性、耐磨性和抗氧化性,并且具有自润滑性能.在日本,金属陶瓷刀具的应用占全部刀具的35%以上,欧美等国也达到20%以上,而在我国,金属陶瓷刀具和陶瓷刀具主要依靠进口,金属陶瓷刀具的使用量仅占刀具总量的3%.由此可见,我国金属陶瓷刀具的研发与生产应用远远落后于发达国家.为实现把我国建设成为全球制造业强国的梦想,必须加快我国金属陶瓷刀具研发、生产与推广应用,以改善加工业的加工精度和产品表面光洁度,提高加工业的加工效率,保证制造业零部件的高质量,全面提高我国制造业水平.虽然Ti(C,N)基金属陶瓷刀具比传统的硬质合金刀具有更好的高温红硬性、耐磨性和抗氧化性,但是冲击韧性、断裂强度较差及高温强度不够是其致命的缺点.为此,国内外学者在Ti(C,N)基金属陶瓷的强韧性方面展开大量的研究工作,并取得了一定的研究成果.研究工作主要集中在:(1)陶瓷相与金属相的成分;(2)烧结工艺;(3)引入纳米增强体.近两年来,由于钼、钴的资源短缺与价格上涨,从实际生产成本和高性能等方面考虑,一些学者还对无钼无钴、掺高熵合金Ti(C,N)基金属陶瓷的性能进行了研究.本文采用比较法,对有关Ti(C,N)基金属陶瓷材料强韧化的研究成果进行了分类、归纳与总结,从而得出了影响 Ti(C,N)基金属陶瓷材料强韧化的三个因素——组成成分、显微结构和烧结工艺,并就此展开讨论;介绍了当前增强增韧 Ti(C,N)基金属陶瓷的三种主要方法——纳米颗粒改性增韧法、晶须增韧法和纤维增韧法;最后提出关于今后 Ti(C,N)基金属陶瓷材料的强韧化研究亟待解决的问题与发展方向.%Ti(C,N)based cermets have been used widely in cutting tools and molds due to their excellent properties of high strength,high hardness,high temperature oxidation resistance,acid and alkali resistance,and abrasion resistance.During high tem-perature machining,cermet tools shows significantly high sticking resistance,thermal stability,and self-lubricating.Their red hard-ness,wear resistance,and oxidation resistance are better than cemented carbide ones.The usage of cermet cutting tools over that of the total cutting tools is more than 35% in Japan and more than 20% in both Europe and US,while in China,the number drops to 3%,indicating that the research,development,as well as the manufacture of cermet tools in China are far behind those in advanced countries.Therefore,it becomes extremely urgent and important to speed up the research,development,manufacture,and applica-tion of cermet cutting tools in China for the purpose of the development of the global manufacturing powerhouse for China,improving the precision and surface smoothness during high speed machining,increasing the machining efficiency of processing industry,gua-ranteeing the machining quality,and elevating the level of manufacture industry of cutting tools in China. The fatal drawbacks of Ti(C,N)based cermet include low impact resistance,low fracture toughness,as well as insufficient high temperature strength in spite of the superior red hardness,wear resistance,and oxidation resistance compared with cemented carbide tools.Therefore,significant research has been made on the strengthening and toughening of Ti(C,N)based cermet globally with some good results.The related research is focused on:Ⅰ.the composition of the ceramic and metal phases,Ⅱ.sintering processes,and Ⅲ.the adoption of nano-enhancement.In recent two years,due to the shortage and high price of Mo and Co,some research has been done on Mo and Co free Ti(C,N)based high-entropy alloys for the sake of low cost and high performance. In this paper,the global research on strengthening and toughening of Ti(C,N)based cermets has been classified,summarized, and generalized.It is found that,based on the current research results,the composition,microstructure and sintering process are the most important factors influencing the strength and toughness of Ti(C,N)based cermets.Three methods for strengthening and toughening of Ti(C,N)based cermets are summarized,including nano-particle toughening,whisker toughening,and fiber toughe-ning.Finally,the urgent unresolved problems are summarized and the development direction is proposed for the strengthening and toughening of Ti(C,N)based cermets.
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