(1. 南华大学 机械工程学院，衡阳 421001；
2. 湖南大学 汽车车身先进设计制造国家重点实验室，长沙 410082)
摘 要: 采用FORTRAN语言建立固体界面一维反热传导的计算程序，结合自制的热电偶测温实验装置，等效研究6061铝合金挤压型材在线弯曲过程中与H13模具钢界面的瞬态换热行为，探讨初始温度、接触载荷、表面粗糙度和热流方向对接触换热系数的影响。结果表明：瞬态换热系数在开始接触的短时间内(5 s)急剧上升，然后缓慢增大至某一稳定值。当界面平均接触温度从111.5 ℃增大到211.5 ℃时，接触换热系数迅速增加。进一步提高界面平均接触温度，接触换热系数增加速率下降；随着表面粗糙度的增大，接触换热系数逐渐减小，在1.66~2.05 μm范围内影响最为显著。随着载荷的增加，接触换热系数逐渐增大，敏感性逐渐下降；热流方向从铝合金到H13钢时的接触换热系数明显要比H13钢到铝合金的接触换热系数大。
关键字: 6061铝合金；H13钢；反热传导；接触换热系数；影响因素
（1. School of Mechanical Engineering, University of South China, Hengyang 421001, China;
2. State Key Laboratory of Advanced Design and Manufacture for Vehicle Body, Hunan University, Changsha 410082, China）
Abstract:A model of inverse heat conduction for solid interfaces was established by using FORTRAN language. The transient heat transfer behavior between 6061 aluminum alloy and H13 steel was equivalently investigated by a self-made device with thermocouple. The influences of initial temperature, contact pressure, surface roughness and heat flux direction on the contact heat transfer coefficient were systematically studied. The results show that the contact heat transfer coefficient increases rapidly to a certain value in a very short time (5 s), from which a much slower increase occurs. When the average contact temperature increases from 111.5 to 211.5 ℃, the contact heat transfer coefficient increases rapidly. But with the average contact temperature further increasing, the increase rate of contact heat transfer coefficient decreases. With the increase of surface roughness, the contact heat transfer coefficient decreases gradually, the most significant effect is in the range of 1.66-2.05 μm. The contact heat transfer coefficient increases gradually with the increase of contact pressure, but the sensitivity gradually decreases. The contact heat transfer coefficient for the heat flux direction from aluminum alloy to H13 steel is obviously larger than that from H13 steel to aluminum alloy.
Key words: 6061 aluminum alloy; H13 steel; inverse heat conduction; contact heat transfer coefficient; influence factors
