摘要
基于静态失重及金相测定法,获得了不同保温时间下典型热冲压钢板22MnB5的高温氧化规律,建立了适用于热冲压钢板氧化失重及厚度减薄的氧化回归方程;并将等效接触换热系数引入到考虑氧化脱碳层的热冲压换热反求数值计算模型中,研究了氧化行为对热冲压过程传热性能的影响规律,分析了氧化脱碳层厚度和载荷因素对等效接触换热系数的动力学影响。结果表明:在900℃加热条件下,保温开始阶段板料的氧化速率较高,4～5min后逐渐减缓。1.6mm冷轧热冲压钢板B1500HS最高单位面积氧化失重为0.471mg/mm2,最大减薄厚度为99.3μm,氧化脱碳层最大深度为87.0μm,氧化过程遵循抛物线规律,其氧化失重与减薄回归方程的复相关系数达0.95以上,拟合程度良好。等效接触换热系数与氧化层厚度的关系呈反比关系,并随界面载荷的增加而增大,氧化行为对热冲压过程传热动力学性能有重要影响作用。
Based on static weight loss method and metallographic method, this paper investigated the effect of soaking time on the oxidation behavior of typical cold rolled hot stamping steel 22MnB5. With the results of the thickness of oxidation and decarburization scales, the regression equations of weight loss and reduction of oxide scales were built. The characteristic parameter named equivalent interfacial-heat-transfer-coefficient （IHTC） was got by inverse numerical calculation with ABAQUS, which was taken to describe the effects of thickness of oxidation and decarburization scales and loads based on related heat transfer dynamics performance in process of hot stamping. The results indicate that the weight loss per unit area and thickness reduction of B1500HS steel with 1.6mm thickness can reach 0. 471 mg/mm2 and 99.3/xm respectively, the depth of decarburization can reach 87.0 μm at 900 ℃. The oxidation of the mentioned steels obeys the parabolic law, which presents high oxidation rate at initial stage of soaking, then slows down obviously after 4 - 5 min. The multiple correlation coefficients between regression analysis and weight loss and reduction of oxide scales are over 0.95. The equivalent IHTC has negative relationship with the thickness of oxidation scale and it also increases with the interface load. The results show that oxidation behavior has a significant influence on heat transfer dynamics performance in hot stamping process.
出处
《吉林大学学报（工学版）》
EI
CAS
CSCD
北大核心
2013年第6期1551-1557,共7页
Journal of Jilin University:Engineering and Technology Edition
基金
国家自然科学基金项目(10932003
11272075)
'973'国家重点基础研究发展计划项目(2010CB832700)
中央高校基本科研业务费专项资金项目(DUT12LK03)
国家工信部04重大专项项目(2011ZX04001-021)
关键词
金属材料
热冲压
22MnB5
氧化行为
接触换热系数
传热动力学
metallic materials
hot stamping
22MnBS
oxidation behavior
interracial heat transfer coefficient
heat transfer dynamics
