机械结合面接触刚度超声波检测方法研究  

Research on measuring contact stiffness of mechanical joint by an ultrasonic method

作　　者：唐伟鑫 殷勤[1] 赵秀粉[1] 殷国富[1] 赵越[1] 李猛[1] 

机构地区：[1]四川大学制造科学与工程学院,四川成都610065

出　　处：《中国测试》2015年第8期8-12,共5页China Measurement & Test

基　　金：国家科技重大专项资助项目(2013ZX04005-012);四川省科技厅应用基础研究项目(2014JY0235)

摘　　要：针对检查机械产品结合部接触刚度特性的需要,进行超声波测量结合面接触刚度与超声波检测频率相关性的研究,基于简单弹簧模型设计一种用超声波测量两钢块结合部接触刚度的实验方案。实验结果表明:超声波反射系数随超声波频率增大而增大;作用于结合面的压力较小时,超声波测量接触刚度随频率没有明显变化;作用于结合面的压力较大时,超声波测量接触刚度随频率有一定波动。在结合面上加入润滑油,模拟工程实践中结合面状态,实验结果表明:因结合面上油膜的存在,在同样大小压力作用下超声波测量的接触刚度相对无油膜时增大。通过以上分析可知简单弹簧模型是有效的,机械结合面处的相互作用可用一个刚度可变的弹簧等效。For the necessity of measuring contact stiffness of mechanical joints, the relationship between the contact stiffness was determined from ultrasonic measurements, and the frequency of ultrasonic wave as well as the influence of oil film on the contact stiffness was studied. An experimental scheme was designed to measure the contact stiffness of two steel blocks by an ultrasonic method. The results demonstrate that the reflection coefficient is almost unchanged with the increasing frequency of ultrasonic wave, and the contact stiffness was unaffected by the frequency of ultrasonic wave under small pressure while fluctuated with the increasing frequency of ultrasonic wave under large pressure. After that, lubricant was added to the joint to simulate an engineering interface, and at the same time, its contact stiffness was measured ultrasonically. By comparing the values of contact stiffness under the same pressure, it is found that the contact surfaces of mechanical joints with lubricant film are more rigid than those without lubricant film. It is proved that a simple spring model is valid, and thus the interaction of mechanical joints can be represented with the springs of a variable stiffness.

关 键 词：机械结合面 超声波 接触刚度 频率 油膜 

分 类 号：TH113.1[机械工程—机械设计及理论]