超高温陶瓷复合材料ZrB2-HfB2-SiC电火花加工蚀除特性研究  

Study on the Material Removal Characteristics of Ultra-high Temperature Ceramic Composites ZrB_(2)-HfB_(2)-SiC Machined by EDM

作　　者：于晴 杨晓冬[1] 段晓明 YU Qing;YANG Xiaodong;DUAN Xiaoming(School of Mechatronics Engineering,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]哈尔滨工业大学机电工程学院,黑龙江哈尔滨150001

出　　处：《电加工与模具》2024年第6期1-7,共7页Electromachining & Mould

基　　金：国家自然科学基金项目(52375419);国家资助博士后研究人员计划项目(GZC20233455)。

摘　　要：ZrB_(2)-HfB_(2)-SiC作为超高温陶瓷复合材料,具有高硬度与高脆性的特点。采用传统机械加工方法,刀具磨损严重,加工效率低。电火花加工不受材料硬度和脆性限制,是加工ZrB_(2)-HfB_(2)-SiC材料的有效方法。但该复合材料具有非均质性和各向异性,材料组分的不同作用机制导致其具有不同于电火花加工金属的材料蚀除过程和蚀除机制。利用高速摄像观测方法对电火花加工ZrB_(2)-HfB_(2)-SiC时的单脉冲放电材料蚀除过程进行研究,分析其蚀除机制。结果表明:该材料在放电蚀除过程中发生了复杂的物理化学变化,SiC纤维主要为断裂蚀除;放电凹坑形状不规则,且不同位置的放电凹坑形貌差异很大。通过电火花微小孔加工实验,验证了电火花加工ZrB_(2)-HfB_(2)-SiC的可行性,发现微细电火花加工时其具有明显的极性效应。ZrB_(2)-HfB_(2)-SiC is an ultra-high temperature ceramic composite material,the machining of such composites using traditional machining methods often faces the challenges of high tool wear and low machining efficiencies,attributed to the high hardness and brittleness of this material.EDM is not limited by the hardness and brittleness of materials,providing an effective machining method for ZrB_(2)-HfB_(2)-SiC.However,the material removal process and removal mechanism during EDM of ZrB_(2)-HfB_(2)-SiC are significantly different from those of conventional metals,attributed to the non-homogeneity and anisotropy caused by the different material components within it.The material removal process during the EDM of ZrB_(2)-HfB_(2)-SiC were investigated by using high-speed camera observation to analyze the material removal mechanisms.The results showed that the material had complex physical and chemical changes during the discharge removal process,and the SiC fibers were mainly removed by fracture.The shape of the discharge pit is irregular,and the morphology of the discharge pit at different positions varies widely.The experimental study of EDM micro-hole machining was carried out to verify the feasibility of EDM ZrB_(2)-HfB_(2)-SiC,and it was found that it had obvious polarity effect.

关 键 词：ZrB2-HfB2-SiC 超高温陶瓷复合材料 电火花加工 蚀除 

分 类 号：TB332[一般工业技术—材料科学与工程]