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研制成功了国内外尚属空白的新型陶瓷刀具材料——碳化硅晶须(SiCw)增韧和碳化硅颗粒(SiCp)弥散补强Al_2O_3陶瓷刀具材料JX-2系列,其硬度为93.5～94.8HAA,抗弯强度为650～750MPa,断裂韧性为7.5～8.5MPa·m~(1/2),并且具有导热性好和成本低等优点。 对原料组分和热压烧结工艺进行了优化设计;证实了晶须和颗粒具有增韧补强的协同作用,根据能量耗散理论,建立了晶须桥联、拔出、裂纹偏转和微裂纹增韧的理论模型;详细研究了该陶瓷刀具材料的界面力学行为及其与材料力学性能的关系,研究了材料的界面作用机理;建立了Al_2O_3/SiCw/SiCp系陶瓷刀具材料界面结合强度L_f和断裂韧性K_(IC)的关系模型,据此可以实现复合陶瓷刀具材料的组分优化设计,缩短复合材料的研制时间。 深入研究了新型复相陶瓷刀具材料的切削性能及其磨损破损机理,并对刀具热磨损和热破损的机理进行了强激光热模拟;研究了该刀具材料力学性能、界面结合强度和刀具破损寿命的随机性,它们的分布规律均较好地服从威布尔分布,首次提出了用界面结合强度评价JX-2陶瓷刀具破损可靠性的新方法。
The successful development of a new type of ceramic tool material - SiCw toughening and SiCp dispersion reinforced Al_2O_3 ceramic tool material JX-2 series with a hardness of 93.5 ~ 94.8HAA , Flexural strength of 650 ~ 750MPa, fracture toughness of 7.5 ~ 8.5MPa · m ~ (1/2), and has the advantages of good thermal conductivity and low cost. The composition of the raw materials and the hot-pressing sintering process were optimized. The synergistic effect of toughening and strengthening of the whiskers and particles was confirmed. According to the energy dissipation theory, the whiskers bridging, pulling out, crack deflecting and microcracking Toughening theoretical model; the interface mechanical behavior of the ceramic tool material and its relationship with the mechanical properties of the material were studied in detail; the interfacial interaction mechanism of the material was studied; and the interfacial bonding strength L_f of the Al_2O_3 / SiCw / SiCp ceramic tool material Fracture toughness K_ (IC) relationship model, which can be achieved composite ceramic tool material composition optimization design, shorten the development time of composite materials. In-depth study of the cutting performance of the new multi-phase ceramic tool material and its wear and tear damage mechanism, and the thermal wear and thermal damage of the tool mechanism of intense laser heat simulation; mechanical properties of the tool material, the interface bonding strength and tool life The randomness and their distribution rules are well obeyed by Weibull distribution. For the first time, a new method to evaluate the fracture reliability of JX-2 ceramic tool by interface bonding strength is proposed.