对金刚石线锯在超声作用下的力学性能进行实验研究.自行设计振动系统及连接装置,利用超声振动对不同直径金刚石线锯进行单向拉伸试验,研究不同频率、不同振幅下材料力学性能的变化.用电子金相显微镜对有/无超声作用下的断口形貌进行分析,研究超声拉伸下金刚石线锯裂纹扩展机理和软化机理.实验结果表明:超声振动拉伸作用下,材料内部产生交变应力,出现微裂纹,裂纹扩展并快速撕裂,高频振动产生局部的高温,加速扩散过程发生,最终发展成宏观缺陷.当超声振动载荷频率为20 kHz时,裂纹扩展速率达到10-9~ 10-8 mm/cycle.%Mechanical properties of diamond wire saw under the action of ultrasonic vibration were studied.The vibration system and connection device were self-designed, and the uniaxial tensile tests were carried out for different diameters of diamond wire saw by use of the ultrasonic vibration system in an attempt to find the changes in mechanical properties of diamond wire saw under different frequencies and different amplitudes.Diamond wire saw crack growth mechanism and softening mechanism under the condition of ultrasonic tension were studied.Wire saw fracture morphology were analyzed using electron metallographic microscope with or without ultrasonic vibration.Results showed that the alternating stresses of wire saw were generated under the action of ultrasonic vibration, and that there appeared micro-cracks, which rapidly expanded and teared.High frequency vibration produced localized high temperature and accelerated diffusion process, which eventually developed into a macro defect.When the ultrasonic stretching frequency was loaded to 20 kHz, the crack growth rate could reach 10-9 ~ 10-8 mm/cycle.
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