在生产过程中,必须对点焊接头质量进行无损检验。在一般情况下,可以采用X射线照相和超声波检验技术,但它们都有各自的局限性。因此,需要研制一种快速、定量的无损检验方法,以得到常规的制取一系列金相试片才能得到的结果。本文论述的四点式电阻测量法解决了这个问题。两金属零件点焊时,借助于电流使金属重新结晶 In the production process, the quality of spot welding joints must be inspected non-destructively. Under normal circumstances, you can use X-ray radiography and ultrasonic testing technology, but they all have their own limitations. Therefore, there is a need to develop a rapid and quantitative non-destructive testing method to obtain the results obtained by conventional preparation of a series of metallographic test strips. This article discusses the four-point resistance measurement to solve this problem. When two metal parts are spot welded, the metal is recrystallized with the aid of current