超高压封垫材料力学性能的测试技术

A MATERIAL TEST TECHNIQUE FOR SUPER-HIGH PRESSURE GASKET MATERIAL

本文在现有的压扭法和圆片挤压法测试技术的基础上,提出了理论模型更准确、测试更简便、精度更高的纯内滑移法。在纯内滑移法的测试过程中,封垫材料的塑性变形只发生在试样内部,从而排除了压扭法或圆片挤压法中砧子表面摩擦状态对测试结果的影响。本文采用纯内滑移法研究了叶蜡石在不同焙烧温度和吸湿程度下的力学性能,得出了一些有意义的变化规律。

The mechanical properly of super-high pressure gasket material-pyrophyllite is studied in this paper. Based on the analysis of the press shear and the disc-squeeging methods, a new material test technique-pure inetrnal slipping method is suggested. The principal advantage of this method is that the friction between the sample and dies has no influence on test results, so that the test results are perfactly determined by the plastic property of sampler According to this idea, a simple device is set up and a series of tests on the mechanical properly of pyrophylite are carried out. On the other hand, a programme for stress distribution analysis in the plastic region of samples by slip-line theory is worked out. By using this programme, the relation between the average pressure p. cohesion K. internal friction angle p and the diameter-thickness ratio d/h can be calculated, and the procedure for calculating the material parameter K, p from the test results p - d/h is suggested. The lest results show that the fired tempera-lure and the moisture have strong influence on the mechanical property of samples and some rules exist between them.