摘要
基于正交试验法,用Gleeble试验机对35CrMo钢棒进行了单向热压连接模拟实验。通过室温拉伸获得的伸长率比值为愈合率判据并辅以显微组织分析,发现在1 000~1 200℃的典型热锻温度范围内,增加热压变形量比升温更能促进动态再结晶和连接界面上孔隙的弥合,对提高愈合率更为关键。压后保温仅引起晶粒长大,几乎不改变残余孔隙率及愈合率。但压后保温时施加微小压力触发蠕变,则能有效弥合残存孔隙,进一步提高愈合率。分析表明,越有利于增强原子扩散的热压工艺参数,越容易弥合孔隙,让界面由物理连接向冶金连接转变,从而获得更高的愈合率。研究所得实验数据显示,当热压变形量达到60%,保温并继续施加9 MPa的蠕变压力是保证愈合率接近100%的优化工艺参数组合。
Based on the orthogonal analysis,the hot compression bonding experiments were conducted on the 35CrMo bars using the Gleeble 3500 equipment.Through using the elongation ratio obtained by tensile test at room temperature as criterion for healing quality and combining with the microstructural characterization,it showed that within the typical temperature range 1000-1200℃for hot forging,the increase in compression amount is more critical than temperature to improve the healing quality,which could improve dynamic recrystallization and decrease porosity at joint interface.Holding temperature after compression only causes the grains grow,rarely affecting the porosity as well as healing quality.However,a small pressure during holding temperature after compression could cause creep,which could eliminate the residual pores,improving the healing quality.Analysis shows that the processing parameters beneficial to rapid atomic diffusion help obtain better healing quality due to the significant decrease of porosity and the conversion of atomic binding from physical to metallurgical manner.To reach the best healing quality,the optimized processing combination including a compression amount of 60%plus a maintaining pressure of 9 MPa during holding is recommended based on present experimental results.
作者
陈一安
仝珏川
郭正洪
顾剑锋
CHEN Yian;TONG Juechuan;GUO Zhenghong;GU Jianfeng(Institute of Materials Modification and Modeling,Shanghai Jiao Tong University,Shanghai 200240,China;Shanghai Key Laboratory of Materials Laser Processing and Modification,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2024年第11期1449-1459,共11页
Journal of Iron and Steel Research
基金
国家重点研发计划资助项目(2018YFA0702900)。
关键词
热压连接
正交试验
动态再结晶
蠕变
原子扩散
hot compression bonding
orthogonal experiment
dynamic recrystallization
creep
atomic diffusion
