基于Miller薄板压缩夹具的试验拧紧力矩研究

Study on Experimental Tightening Torque based on Miller Fixture for Sheet Compression

使用Miller夹具进行了铝合金挤压型材薄板压缩屈服强度试验,通过分析不同拧紧力矩下的测试结果,对比有限元分析的薄板试片失稳形态与测试后试片的变形情况,发现使用Miller薄板压缩试验夹具测试压缩屈服强度时,拧紧力矩不足使得试片在压缩屈服之前失稳,导致测试结果失真,拧紧力矩过大引起摩擦力显著增大,会导致测试结果偏危险。在使用聚四氟乙烯薄膜代替二硫化钼作为润滑材料的情况下,建议测试铝合金挤压型材压缩屈服强度的试验拧紧力矩为0.02N·m。

In this paper,the Miller fixture is used to test the compressive yield strength of aluminum alloy extruded sheet.By analyzing the test results under different tightening torques,and comparing the deformation of sheet specimen analyzed by FEA and the deformation of the tested specimen,it is found that when use the Miller fixture to test sheet compression yield strength,the smaller tightening torque makes the test specimen instable before the compression yield and makes the result distorted,and the bigger tightening torque causes a significant increase in friction,which will lead to dangerous test results.In the case of using polytetrafluoroethylene film instead of molybdenum disulfide as the lubricating material,it is recommended to test the compressive yield strength of the aluminum alloy extruded profile with a experimental tightening torque of0.02Nom.