预热对HG70钢C02气体保护焊焊接接头-湖南工学院.PDF

金晨铸锻焊技术ICasting·Forging·Welding 2伽阿年4月 ●焊接技术● 预热对HG70钢C02气体保护焊焊接接头 组织与性能的影响 林高用1．孙利平1．万迎春1．任芝兰¨ (1．中南大学材料科学与工程学院教育部有色金属材料科学与工程重点实验宣。湖南长沙410083；2．湖南工学院 机械系，湖南衡阳421101) 摘要：在焊前不预热、预热100℃和预热150℃的条件下进行HG70钢C02气体保护焊，分析了预热对焊接 接头显微组织和力学性能的影响。结果表明：焊前预热使HG70钢焊接接头组织改善，硬度下降，淬硬倾向降低， 塑性、韧性提高，强度稍有降低。 关键词：HG70钢；C02气体保护焊；预热；焊接接头 中田分类号：TG406；TG444．73文献标识码：A 文章编号：1001-3814(2009)07-0094-03 Effectof onMicrostructureandMechanical ofHG70 Preheating Properties SteeIWeldedwith GasShieldedArc Joint C02 Welding Zhilanu Yingchun‘，REN L矾Gaoyon91，SUNLipin91，WAN MetalsMaterialsSdenceand Education,School (I．TheKeyLaboratoryofNonferrous Engineering,MiniJtryof of MaterialsScience South Hurum Institute and西lg打圮e而眵Ce．ntraiUnivenily,Cha,咖410083，China；ZEngineering 421 Department旷Mechanics，llengymlg101，ch／眦) w雠conductedOilconditionofno at100℃，and Abstract：Weldingexperiments preheating,preheating at1 arc effectsof 011microstructureandmechanical 50(2 shielded preheating usingC02gas welding．Thepreheating ofHG70steelweldedWere remitsshowthat themicrostructureof properties joint analyzed．The preheatingimproves steelweldedTheh剐旧瞄sandthetrendofharden oftheweldeddecw．ase．the HG70 jomL quenching joint plasticity and thetensile decreases increase。and sU,ength slightly． ductility words：HG70steel；C02 Key gasshielded锄陀we