厚壁16Cr不锈钢管高频焊接工艺优化及管接头性能

摘要

The microstructure and formability of weld for 16Cr stainless steel plate with 3.4 mm thickness by high frequency welding method in different welding parameters were studied,and the welding process was optimized.Then the properties of 16Cr stainless steel welded pipe joint under optimized process were studied by tensile test,flattening test and flaring test.The results show that welded joint with excellent formability was obtained when welding speed was 10 m· min 1 and welding heat input was 3.0 kJ · cm-1.The microstructure of weld was composed of austenite and δ-ferrite.Although the welded pipe had high strength,the toughness got worse due to the presence of oxide inclusions in the weld.The oxide inclusion in the weld could be effectively reduced by application of appropriate gas protection and avoiding high temperature weld contacted with water.%通过高频焊接方法在不同工艺下焊接3.4 mm厚16Cr不锈钢板,分析了焊缝的显微组织及成形性能,并对其焊接工艺进行了优化;之后通过拉伸、压扁和扩口试验等方法研究了优化工艺下制备16Cr不锈钢焊管接头的性能.结果表明:在焊接速度10 m·min-1,焊接热输入3.0 kJ·cm-1时可获得成形性能良好的焊接接头,焊缝的组织为奥氏体和δ铁素体;制备的焊管虽然具有较高的强度,但焊缝处存在的氧化物夹杂使其韧性变差;采用适当的气体保护和避免水与高温焊缝的接触可有效地减少焊缝氧化物夹杂的产生.