瑞利波无损评价薄镀层应力方法的试验  

Study on stress measurement of thin plating coating with Rayleigh wave

作　　者：刘彬[1,2] 董世运[2] 徐滨士[2] 何鹏[1] 

机构地区：[1]哈尔滨工业大学先进焊接与连接国家重点实验室,黑龙江哈尔滨150001 [2]装甲兵工程学院再制造技术重点实验室,北京100072

出　　处：《材料热处理学报》2012年第3期110-113,共4页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金资助项目(50975287)

摘　　要：结合力学静载拉伸试验,采用声程固定的5 MHz的双瑞利波探头对电刷镀层应力进行评价。结果表明,随着拉伸应力的增加,瑞利波在电刷镀层中的传播速度呈线性规律增加,当拉伸应力达到104 MPa时,时间差达到最大值180 ns;再随拉伸应力的增加,瑞利波在电刷镀层中的传播速度呈"跳跃式"变化。采用超声显微成像方法对承受不同载荷的电刷镀层进行检测结果表明,微裂纹是造成电刷镀层应力-时间差呈"跳跃式"变化的主要原因。在分析镀层平整度及镀层变形程度对评价结果影响的基础上,得到可用于评价镀层应力的声弹性公式,验证结果表明采用该方法对镀层应力进行评价是可行的。Based on tensile experiment,two Rayleigh wave probes with 5 MHz frequency as a transmitter and receiver were employed to collect Rayleigh wave single in brush electro-plating coating and stress in the brush electro-plating coating was measured.Results show that propagation velocity of Rayleigh wave in brush electro-plating coating linearly increases as tensile stress increasing,when tensile stress reaches 104 MPa,the time difference between Rayleigh wave signal and the reference singnal reaches the maximum value of 180 ns,and while the propagation velocity of Rayleigh wave in the coating presents fluctuating as further increasing tensile stress.Result of ultrasonic imaging amalysis shows that the above result is mainly caused by microcrack in the coating.Based on analysis of flatness and deformation of the coating,an acoustoelastic formula of Rayleigh ware is obtained and the formula can be used to evaluate the stress in the coating.

关 键 词：电刷镀层 瑞利波 拉伸应力 传播速度 

分 类 号：TG115.2[金属学及工艺—物理冶金]