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针对传统宏观力学研究涂层的局限性,开展了基于Hertz理论的等离子喷涂Fe Cr BSi涂层有限元数值模拟研究,得到了涂层表面在不同载荷和摩擦力作用下,涂层主应力与剪切应力的分布特征。分析结果表明:主应力是接触疲劳失效的临界应力,而剪切应力则导致涂层在微缺陷处在较短的时间内诱发萌生微裂纹,不同主应力与剪切应力的协同作用使得涂层失效模式呈现多元化,应力是涂层失效的主要驱动力。摩擦系数的增加导致剪切应力急剧增加,剪切应力造成涂层表面的塑性流动。当塑性流动超过材料的变形极限时,造成表面材料开裂,在循环作用下最终形成裂纹。同时摩擦系数的增加加大了涂层与对摩轴承直接接触相互损伤的可能性。
In view of the limitation of traditional macroscopic mechanics research coating, the finite element numerical simulation of plasma sprayed Fe Cr BSi coating based on Hertz theory was carried out. Under different load and frictional force, The distribution of shear stress. The results show that the main stress is the critical stress of contact fatigue failure, and the shear stress causes the coating to induce germination microcracks in a short time at micro defects. The synergistic effect of different principal stress and shear stress makes the coating The failure mode is diversified, and stress is the main driver of coating failure. The increase of the friction coefficient leads to the sharp increase of the shear stress, which causes the plastic flow on the coating surface. When the plastic flow exceeds the deformation limit of the material, the surface material is cracked and the crack eventually forms under the action of the circulation. At the same time, the increase of friction coefficient increases the possibility of mutual damage between the coating and the friction bearing.