载荷对接触热导的影响的实验研究

Research of Loading Effect on Thermal Contact Conductance by Using Expermental Method

接触界面热导是工程热设计中的一个重要参数,目前国内外普遍采用稳态法进行测量,但该法不能测试大塑性变形下的接触热导。在许多工程应用如双辊连续铸轧中,材料发生大应变塑性变形,其变形率达到50%以上,本文利用瞬态法对大变形条件下的接触热导进行了测试,测试结果表明当接触压力远远超过接触试样中硬度较小的试样的屈服极限以后接触热导变化趋于平缓,接触热导值相对于小压力条件有显著提高。

Contact conductance is an important parameter in thermal engineering design.Generally,it is tested with stable method home and abroad, but this method can not test contact conductanceunder large plastic deformation. In many engineering field such as during the course of twinroller continuous casting process, materials have big strain deformation, and the deformation usually reaches 50% or above. In this article , transient method is extended to test contact conductance under condition of large deformation, the testing result indicate that when the contact pressure surpassing the yield limit of the softer material to a great extent, contact conductance fluctuates a little, contrast to the condition of small pressure, the testing results increase in large amount.