核电主管道材料316LN钢塑性成形过程晶粒细化  

Grain refinement during plastic forming of 316LN steel used in nuclear main pipes

作　　者：潘品李[1] 钟约先[1] 马庆贤[1] 袁朝龙[1] 

机构地区：[1]清华大学机械工程系,先进成形制造教育部重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2013年第3期289-294,共6页Journal of Tsinghua University(Science and Technology)

基　　金：国家科技重大专项(2012ZX04012-011)

摘　　要：AP1000核电主管道材料为316LN,该钢种无法通过热处理细化晶粒,需在锻造过程中保证产品的晶粒度要求。该文研究了316LN钢单道次和多道次变形条件下的动态再结晶行为,获得316LN钢在锻造成形中的晶粒细化判据;提出了上平下V砧的改进砧形,对锻件采用大圆角V砧以及上下不等砧宽比进行拔长,采用数值模拟和物理模拟相结合的方法,研究了拔长过程应力应变分布规律,并确定合理的工艺参数,有效地提高锻件变形区域的等效应变及均匀分布,达到锻件变形均匀和晶粒细化的目的。该结果对核电主管道锻造工艺方案优化具有理论参考价值。The grains in 316LN steel used in the nuclear main pipes of the AP1000 cannot be refined by heat treatment. Consequently, forging is used to refine the grain structure. The grain refinement is related to the dynamic recrystallization behavior of 316LN steel for both single-pass and multi-pass deformation. Refined anvils for the upper flat and lower V-shaped anvil are used to give a large fillet and different blank width ratios with the stress and strain distributions then investigated using numerical and modeling simulations. Then, the appropriate process parameters are determined to improve the strain and homogeneity in the forging deformation area to give homogeneous deformation and grain refinement in the forgings. The results can be used to optimize the forging of nuclear main pipes.

关 键 词：锻造工艺 核电主管道 数值模拟 物理模拟 

分 类 号：TG316[金属学及工艺—金属压力加工]