20G管材在往复循环载荷作用下的磁记忆信号分析

本文利用TSC-1M-4型磁应力集中检测仪对20G管材在循环往复载荷作用下进行实验研究,并对检测结果进行磁记忆信号分析。结果表明,应力集中线过零点并不能判定为试件的应力集中点。随着疲劳载荷加载力的减小,构件濒临破坏和达到破坏时的漏磁场梯度值也会随之增大。在应力集中区,20G管材的漏磁场梯度值达到12A/（m.mm）已处于频临破坏的状态,在达到23A/（m.mm）左右时,试件会有明显的疲劳裂纹产生。

Signals Analysis from Magnetic Memory Testing of 20G Steel Under Periodic Loading

Magnetic stress concentration detector TSC-1M-4 was used to test 20G tubular product,and signal processing software was used to analyse test results under periodic loading.The results showed that the line of stress concentration is zero,which could not judge the point as stress concentration.Coupled with the reduction of fatigue load loading force,when component was on the brink of destruction or achieves the destroyed point,leakage magnetic field gradient value would increase.In the area of stress concentration,20 G tubular product leakage magnetic field gradient value up to 12 A /（m·mm）specimen was already in the state of the damage.When the value reached 23 A/（m·mm）,significant fatigue crack of specimen would appear.