摘要
针对直接冷弯成形工艺制备的高强度钢方管出现弯角力学性能下降、冷作硬化效应明显和残余应力集中等问题,提出了在线局部感应回火工艺.该工艺有效解决了冷成形高强度钢方管角部缺陷问题,并发现不同感应回火温度对弯角力学性能有较大的影响.结果表明:当回火温度在650℃时,方管弯角处强度和延伸率与原材料性能接近,在酸洗压扁实验中的压下量超过方管对角线1/2仍没有裂纹出现,残余应力大小和分布也得到一定程度的改善;当回火温度为700℃时,高强度钢方管弯角强度开始降低,热影响区变大,残余应力分布异常.
For the problems caused in the cold-formed process at corners of high strength steel square tube, i.e. poor mechanical properties, severe hardening and residual stress concentration, a local induction tem- pering process on-line was proposed. This process could effectively solve the problems of corner defects of cold-formed high strength steel square tube. The study found that the different tempering temperatures had a great impact on the mechanical properties of the bending angle. The results showed that the strength and elongation of the tempering square tube were almost the same as those of the vigor material at tempe- ring temperature of 650℃. There was no crack when the displacement distance was larger than 1/2 of di- agonal length at flattening test. The magnitude and distribution of the residual stresses had also been im- proved to some extent. As the tempering temperature was 700 ℃, the strength of the high strength steel square tube decreased, the heat affected zone became larger, and the distribution of the residual stresses got abnormal.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2017年第4期438-443,共6页
Journal of Shanghai Jiaotong University
关键词
高强度钢方管
冷成形
局部感应回火
力学特性
high strength steel square tube
cold-formed
local induction tempering
mechanical property
