不锈钢弯头煨弯内壁开裂原因分析

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中图分类号：TG156 文献标识码：B 文章编号：1003-0514（2025）06-0012-06

Analysis of the causes of inner wall cracking in stainless steel elbow bending

Li Xin

（Liaoyang Petrochemical Machinery Design and Manufacturing Co.Ltd.，Liaoyang 111Ooo，Liaoning，China）

Abstract：To investigate thecausesofiner wallcrackingduringthehotinductionbending processof WP304 stainlessteel elbows in a company，asystematic study was conducted onthe failed elbowsusing methods such aschemicalcomposition analysis，tensiletest，rdestest，etalogaphiceamination，macroscopicaalysis，Sanalysis，ndSEDaalis. The results show thatthe chemical compositionand tensile propertiesof the elbows meet therequirements of WP304 in theASTMA4O3Mstandard;themicrostructure isaustenite，andtherearenoabnormalities innon-metalicinclusions;the hardnessoftheouterwallishigherthanthatoftheinnerwallandthe1/2wallthicknessarea.Combinedwiththeanalysis ofthecharacteristics of the hot inductionbendingprocess，itis found that the α -ferriteand intergranularcarbidesin the raw material steel pipedidnotdecompose during therapid induction heating process.Athigh temperatures，thedeformation coordination between the phase interfaces of austenite and α -ferriteis poor，and the deformation abilityof carbides is weak， whichleads to the separation of phase boundaries and grain boundaries during hot induction bending， eventually causing cracking oftheinnerwallofthepipe.Thisstudyprovidesatheoreticalbasisfortheoptimizationofthehot inductionbending process of stainless steel elbows.

Key words： stainless steel; induction bending;crack;α-ferrite; intergranular carbide

0引言

不锈钢无缝钢管制弯头因具有优异的耐腐蚀性、力学性能及加工性能，在石油化工、能源等领域得到广泛应用。（剩余4071字）