摘要
利用CO_2激光对1Cr5Mo耐热钢焊接接头进行退火处理,通过拉伸实验分析温度对激光退火前后试样热拉伸性能的影响。采用扫描电镜观察激光退火前后晶粒变化情况、断裂形式和断口形貌,并通过X射线应力仪测定激光退火前后焊接接头表面残余应力状态。结果表明:在200℃时激光退火后试样的屈服强度、抗拉强度和伸长率比原始试样分别提高了32.5%,22.5%和4.6%,而在300℃时激光退火后试样的屈服强度、抗拉强度和伸长率比原始试样仅分别提高了6.6%,6.5%和7.5%;激光退火前后试样拉伸断口均为韧性断口,但激光退火后试样的韧窝尺寸大于原始试样,随着温度升高,韧窝尺寸进一步增大;激光退火后试样表面产生的晶粒细化和残余压应力是热拉伸性能提高的主要因素。
The lCr5Mo heat-resistant steel welded joint was annealed with C02 laser,the effect of temperature on hot-stretching properties of the samples before and after laser annealing was analyzed by using stretching tests.The grain changes,rupture modes and fracture morphologies before and af-ter laser annealing were observed by SEM,and the status of residual stress on the surface of welded joints was measured by using X-ray stress analyzer.The results show that the yield strength,tensile strength and elongation rate of the samples after laser annealing at 200°C increase by 32.5%<,22.5%and 4.6%than those of the original samples,respectively,while after laser annealing at 300〇C,they only increase by 6.6%,6.5%and 7.5%,respectively;the tensile fracture of the samples before and after laser annealing is tough fracture,but the dimple size of the samples after laser annealing is bigger than that of the original samples,with the increase of temperature,the dimple size increases further;the grain refinement and residual compressive stress generated on the surface of the samples after laser annealing are the main factors of hot-stretching properties improvement.
作者
郭卫
孔德军
GUO Wei;KONG De-jun(School of Mechanical Engineering,Changzhou University,Changzhou 213164,Jiangsu,China;Changzhou High Technology Research Key Laboratory of Mould Advanced Manufacturing,Changzhou University,Changzhou 213164,Jiangsu,China)
出处
《材料工程》
EI
CAS
CSCD
北大核心
2018年第2期115-121,共7页
Journal of Materials Engineering
基金
江苏省研究生科研创新计划项目(CXLX14-1098)
江苏省科协首席专家(工程师)项目(2013-216)
