第40卷第4期压力容器2023年4月doi:■■■■■■■■■■■■■■■■■■■■■■■■10．3969/j．issn．1001－4837．2023．04．011制造与安装不锈耐热钢晶粒过粗对焊接接头的负面影响探析束润涛(武汉市润之达石化设备有限公司，武汉430200)摘要:介绍了国内外承压设备用材标准对不锈耐热钢晶粒度的规定，通过对几个失效案例的具体分析，明确了粗大晶粒会增加晶间腐蚀的敏感性，且在焊接热输入过大的情况下，粗大晶粒会阻碍焊缝收缩时的晶界滑移，增加焊接接头产生裂纹的风险。通过分析，认为晶粒粗大降低了晶界的总面积，随着晶界面积的减少，热影响区在焊接热循环过程中使碳化物更多地聚集于晶界，使得晶界熔合区和热影响区形成裂纹的可能性更大。提出了在严格按焊接工艺施工的前提下，对母材规定合理的晶粒度范围。建议对不锈耐热钢板材、管材和管件的晶粒度按4～9级，锻件的晶粒度按3～7级进行规定。关键词:不锈耐热钢;晶粒粗大;失效中图分类号:TH142;TG115．21;T－65文献标志码:BAnalysisonthenegativeeffectofcoarsegrainofstainlessheat-resistantsteelonweldedjointSHURuntao(WuhanRunzhidaPetrochemicalEquipmentCo．，Ltd．，Wuhan430200，China)Abstract:Thegrainsizeofstainlessheat-resistantsteelinthedomesticandforeignstandardsofmaterialsforpressureequipmentwasbrieflysummarized．Throughtheanalysisofseveralfailurecases，itwasclearthatcoarsegrainwillincreasethesensitivityofintergranularcorrosion，andwhentheweldingheatinputistoolarge，thecoarsegrainwillhindergrainboundaryslipduringweldshrinkageandincreasetheriskofcrackingoftheweldedjoint．Itisconsideredthatthecoarsegrainreducesthetotalareaofgrainboundary，withthedecreaseofthegrainboundaryarea，theheat-affectedzonemakesthecarbidesaccumulatemoreinthegrainboundaryduringtheweldingthermalcycle，makingagreaterpossibilityofcrackformationingrainboundaryfusionzoneandheataffectedzone．Itwasputforwardthatreasonablegrainsizerangeofbasemetalshouldbestipulatedonthepremiseofstrictlyfollowingweldingprocess．Itissuggestedthatthegrainsizeofstainlessheat-resistantsteelsheet，pipeandpipefittingshouldbeclassifiedinto4～9grades，andthatofforgingsshouldbeclassifiedinto3～7grades．Keywords:stainlessheat-resistantsteel;...
