HQ130钢熔合区微裂纹扩展形态及断口特征  

CRACKING MORPHOLOGY AND FRACTURE CHARACTERISTICS IN THE FUSION ZONE OF HQ130 STEEL

作　　者：邹增大[1] 李亚江[1] 

机构地区：[1]山东工业大学,济南250061

出　　处：《机械工程学报》1999年第6期70-73,92,共5页Journal of Mechanical Engineering

基　　金：山东省自然科学基金

摘　　要：通过“铁研”、金相和扫描电镜（ＳＥＭ）试验，对ＨＱ１３０ 高强钢焊接熔合区微裂纹扩展和断口形貌特征进行了研究。试验结果表明，ＨＱ１３０ 钢焊接裂纹大多起源于距熔化边界线２０～６０ μｍ 的半熔化区，一般是平行于熔合区扩展或是越过熔合区拐向焊缝中。裂纹扩展在焊缝区和半熔化区之间交替进行，并非严格按Ｗ／Ｆ界面破断。控制焊接线能量（≤２０ ｋＪ／ｃｍ ）可避免熔合区附近出现粗大的板条马氏体或上贝氏体。Cracking propagation and fracture morphology characteristics in the fusion zone of HQ130 high strength steel are studied by means of “the y slit test”, microscope and SEM. Experimental test indicated that welding crack commonly produced in the partially melted zone at about 20μm～60μm from the melting line and propagated parallel to the fusion zone or turned into the weld metal. Crack propagation conducts alternatively between the weld zone and the partially molten zone, and is not strictly to rupture at W/F boundary surface. Controlling weld heat input (≤20kJ/cm) may avoid forming coarse lath martensite or upper bainite nearby the fusion zone, and welding crack can be effectively prevented.

关 键 词：高强钢 焊接熔合区 微裂纹 断口形貌 焊接 

分 类 号：TG404[金属学及工艺—焊接] TG457.11