摘要
基于有限元软件ABAQUS,利用Norton蠕变本构关系及镍基钎料BNi-2和不锈钢母材SS304在600℃的蠕变参数,对不锈钢板翅结构进行蠕变有限元分析,预测其在高温环境下服役105h的应力、应变分布规律和危险位置．利用有限元分析获得了板翅结构在钎焊过程中产生的残余应力的分布规律,讨论了残余应力对蠕变变形的影响．结果表明,由于钎料和母材力学性能参数的不匹配以及钎焊夹具的约束作用,产生了较大的残余应力,对板翅结构的蠕变变形产生较大影响,故在板翅结构的高温强度设计中,残余应力不可忽略．钎角处蠕变应力和应变集中,易萌生裂纹,成为最薄弱的环节．
According to Norton creep constitutive equation and 600℃ creep parameters of ascast Ni-based BNi 2 filler and SS304 stainless steel, 10^5 h creep analysis for stainless steel plate-fin structure was carried out by ABAQUS finite element code. The creep strain and stress distributions of plate-fin structure were obtained. The creep deformation and the most dangerous position during high temperature service were predicted. The residual stress generated during the brazing process was also simulated and its effect on the creep has been discussed. Due to the mismatch of mechanical properties between filler metal and base metal, the welding residual stress was generated inevitably, which has great influence on the creep deformation and life. Especially, the creep strain and stress are concentrated in the fillet, where the crack would initiate and failure occur.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第5期539-545,共7页
Acta Metallurgica Sinica
基金
国家自然科学基金项目10472043
江苏省自然科学基金预研项目BK2004214
江苏省六大人才高峰项目06-D-035资助
关键词
板翅结构
钎焊残余应力
蠕变
有限元
plate-fin structure, brazed residual stress, creep, finite element method
