摘要
结合软件的二次开发,对403不锈钢锻件加热过程进行有限元数值模拟,研究结果发现:403不锈钢锻件同一位置,倒置入炉的加热温度明显高于正置入炉的加热温度,保温1.5h,表面同一位置的温度相差约20℃,而越靠近心部,相同位置的温度差别越小;工件正置随炉升温,淬火工艺保温时间1.5 h不足以使锻件心部完成奥氏体化,有大量的铁素体和碳化物残留,心部的最低温度比完全奥氏体化温度760℃还约低70℃,将保温时间延长至3.0h,表面最高温度达到952℃,心部最低温度达到873℃,铁素体及碳化物完全转变为奥氏体;然而,当热处理炉温度达到970℃后,再把工件放入炉中加热7.0 h,工件表面及心部温度达到964~970℃之间。在随炉加热过程中,锻件内的应力先增大后减小,入炉方式对Mises应力分布的影响较小。但工件随炉升温与热处理炉到温970℃后放入工件相比,后者的等效应力明显比前者的等效应力大,并且应力峰值出现的时间大幅度的提前。
Finite element numerical simulation was employed on quenching heating process of 403 stainless steel forging by coupled user subroutine.Simulation results show that the temperature of upturned forging is significantly higher than the upright at the same reference position after heating same time and it is below approximately 20℃at the surface of forging,but the difference is smooth with the closer to the core of forging after holding for 1.5 h.When upright forging,the holding time of 1.5 h is not enough to make the core of forging complete austenitization,and there are a large number of ferrite and carbide residues,and the minimum temperature of the core is below 70℃than the full austenitization temperature 760℃.If the holding time is expanded to 3.0 h,the highest surface temperature is 952℃and the lowest core temperature is 873℃.The ferrite and carbide are completely transformed into austenite.However,the forging temperature of surface and core can reach between 964℃and 970℃after holding 7.0 h if the furnace already have reached 970℃.In the process of heating with the furnace,the stress increases with the heating time and then decreases.However,compared cold furnace charging with hot furnace charging at 970℃,the equivalent stress of the latter is obviously larger than the equivalent stress of the former,and the time of stress peak is greatly shifted to much earlier.
作者
朱有鑫
李萌蘖
卜恒勇
李绍宏
张自生
Zhu Youxin;Li Mengnie;Bu Hengyong;Li Shaohong;Zhang Zisheng(Faculty of Materials Science and Engineering,Kunming University of Science and Technology,Kunming Yunnan 650093,China;Guizhou Aerospace Xinli Forging and Casting Co.,Zunyi Guizhou 563003,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2019年第7期18-23,共6页
Heat Treatment of Metals
基金
科技部重点研发项目(2017YFB0701804)
关键词
403不锈钢
数值模拟
热处理
保温时间
入炉方式
403 stainless steel
numerical simulation
heat treatment
holding time
charging mode
