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自行研制的摩擦磨损装置与轴向疲劳试验机相互配合,实现GDL-1钢试样在疲劳应力(240~280 MPa)及接触载荷(30 N)作用下摩擦磨损疲劳试验.通过对磨损层厚度的分析,研究试样承受摩擦磨损载荷及拉压疲劳载荷双重作用下的疲劳寿命变化,用SEM扫描电镜观察分析次表层内疲劳裂纹扩展的演变过程,并采用Hertz线弹性理论和Smith接触理论计算分析摩擦表面以下切应力值.结果表明:在磨损疲劳载荷作用下,形变层的流变作用将显著影响疲劳小裂纹扩展方向,渐趋于切应力方向,从而提高试样疲劳寿命.在此基础上,建立了在摩擦磨损疲劳载荷下疲劳裂纹扩展模型.此外,计算可知在距表层深度0.03 mm处切应力最大,0.18 mm以内材料产生塑性变形,导致形变层的形成.
The self-developed friction and wear device cooperated with the axial fatigue tester to achieve the friction and wear fatigue test of GDL-1 steel under fatigue stress (240-280 MPa) and contact load (30 N) The fatigue life of the specimen under the double action of the frictional load and the tension-compression fatigue load was studied. The evolution of the fatigue crack growth in the subsurface was analyzed by SEM scanning electron microscope. The Hertz linear elasticity theory and Smith contact theory The results show that the rheological effect of the deformation layer will significantly affect the direction of fatigue crack growth and tend to shear stress direction, so as to improve the fatigue life of the specimen. , The fatigue crack propagation model under fatigue load of friction and wear is established.Furthermore, it is found that the maximum shear stress at the depth of 0.03 mm from the surface layer and the plastic deformation of material within 0.18 mm cause the formation of deformation layer.