简介:利用扫描电镜观察和能谱分析,研究了A709-50T-2结构用钢探伤不合格的原因。结果表明:中心偏析和大块Nb和Ti的碳或氮化物的形成共同作用,使钢板中心产生裂纹,最终导致了探伤的不合格。
简介:Advancedhighstrengthsteel(AHSS)hasbeenwidelyusedintheautomobileindustry.TheresistancespotweldingperformanceofDP980andQ&P980steelswasstudiedthroughcomparingthetwosteels'weldingcurrentrange,tensileshearstrength(TSS),crosstensionstrength(CTS),weldspots'microhardness,etc.Thefollowingconclusionswereachieved:ItiseasyforbothDP980andQ&P980steelstogetanuggetsizebiggerthan4mm,theyallhaveweldingcurrentrangesexceeding2kAandhighweldstrength.