不锈钢与碳钢容器金属磁记忆检测特性对比分析

为了比较金属磁记忆技术应用于铁磁性与弱磁性材料时表现出的磁记忆特征,对AISI304不锈钢化工原料储罐和Q235B碳钢洗涤塔进行了磁记忆检测,并对碳钢罐体热处理前后的磁记忆特性进行了跟踪检测,结果表明:弱磁性不锈钢储罐母材本身不显示磁性,但是焊缝处具有明显磁性,显示了磁记忆技术在亚稳态不锈钢焊接结构检测中的可行性;碳钢洗涤塔焊接后,磁记忆特性曲线在焊缝处有明显突变,经过热处理后趋于均匀,但未改变焊缝处磁记忆曲线突变和翻转的基本特征.

Characteristics of Metal Magnetic Memory Technique in Testing Stainless Steel and Carbon Steel Vessels

To compare the characteristics of Metal Magnetic Memory Technique(MMMT),a nondestructive testing method applied to two different materials(ferromagnetic and paramagnetic materials),AISI304 and Q235B vessels has been developed by MMMT respectively.The results show that the weak-magnetic AISI304 material becomes magnetic obviously after welding,indicating that the new MMMT method is feasible in testing weak-magnetic materials.It is also demonstrated that the disorderly magnetic signals of pre-heat treat- ment welds of Q235B become uniform after heat treatment.At the same time,heat treatment does not alter the basic characteristic of abrupt change and overturn of magnetic signals at the welds of Q235B vessel.