SiC单晶刻划过程的脆塑性转变特征研究

发布时间：2018-03-26 07:03

  本文选题：SiC单晶　切入点：脆性材料　出处：《人工晶体学报》2016年11期

【摘要】：SiC单晶化学性能稳定、导热系数高、热膨胀系数小、耐磨性能好,广泛用于大功率器件产业。但由于其材料的硬度很大,加工非常困难。脆性材料塑性域加工为提高该类材料的表面质量,降低加工时间和成本提供了有效的途径。本文采用不同刀具角度和刀尖圆弧半径的单点金刚石刀具对4H-SiC单晶进行刻划实验,利用声发射、摩擦力传感器来监测刻划过程中声发射信号强度以及摩擦力的变化,并通过LeicaDCM3D以及SEM观察划痕沟槽表面形貌、切屑状态,综合分析以获得4H-SiC单晶在不同角度、刀尖圆弧半径下塑脆转变的临界切削深度。结果表明,增大刀具角度有利于塑性域加工;在相同条件下,刀尖圆弧半径越大,临界切削深度越大。
[Abstract]:SiC single crystal chemical stability, high thermal conductivity, low thermal expansion coefficient, good wear resistance, widely used in high power devices industry. But because of the hardness of the material, processing is very difficult. The brittle domain of plastic processing to improve the surface quality of the material, and provides an effective way to reduce the processing time and cost. This paper adopts single point diamond cutter in different cutting angle and the radius of scratch test of 4H-SiC single crystal, the use of the acoustic emission, friction sensor to monitor the acoustic emission signal intensity and the change of the friction characterization process, and through LeicaDCM3D and SEM observation of scratch groove surface morphology, cutting conditions, comprehensive analysis to obtain in 4H-SiC single crystal from different angles, critical cutting depth of ductile brittle transition of the nose radius. The results show that the increase of the angle of the cutting tool for plastic processing domain; in the same conditions, the knife The greater the radius of the tip arc, the greater the critical cutting depth.

【作者单位】： 西安理工大学机械与精密仪器工程学院;
【基金】：国家自然科学基金(51575442,51175420) 陕西省机械装备重点实验室(14JS061)资助项目
【分类号】：TN305.1
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本文编号：1666847