Finite element analysis is used to investigate an elastic-plastic coated spherical contact in full stick contact condition under combined normal and tangential loading. Sliding inception is associated with a loss of t...Finite element analysis is used to investigate an elastic-plastic coated spherical contact in full stick contact condition under combined normal and tangential loading. Sliding inception is associated with a loss of tangential stiffness. The effect of coating thickness on the static friction coefficient is intensively investigated for the case of hard coatings. For this case, with the increase in coating thickness, the static friction coefficient first increases to its maximum value at a certain coating thickness, thereafter decreases, and eventually levels off. The effect of the normal load and material properties on this behavior is discussed. Finally, a model for the static friction coefficient as a function of the coating thickness is provided for a wide range of material properties and normal loading.展开更多
对销轴连接的铸钢件承载能力进行试验研究。试验选择100、150、182 mm三种不同厚度的铸钢试件,最大加载拉力为8 000 k N。结果表明:在拉力作用下,铸钢试件发生了不同程度的塑性变形,塑性区面积随试件厚度的增大而显著减小,塑性开展大致...对销轴连接的铸钢件承载能力进行试验研究。试验选择100、150、182 mm三种不同厚度的铸钢试件,最大加载拉力为8 000 k N。结果表明:在拉力作用下,铸钢试件发生了不同程度的塑性变形,塑性区面积随试件厚度的增大而显著减小,塑性开展大致呈剪切型发展。铸钢件与销轴直接承压接触的部位,由于应力集中很快达到屈服;接触变形导致区域内应力重分布,部分测点应变减小,甚至出现拉压应变反转的现象。与有限元分析结果对比表明,偏心受力会使铸钢件与销轴接触部位在加载初期产生较大应力集中。将承载力的试验结果与采用各国规范设计公式计算的结果进行对比,建议承载力计算公式中设计强度提高系数取为1.2。展开更多
文摘Finite element analysis is used to investigate an elastic-plastic coated spherical contact in full stick contact condition under combined normal and tangential loading. Sliding inception is associated with a loss of tangential stiffness. The effect of coating thickness on the static friction coefficient is intensively investigated for the case of hard coatings. For this case, with the increase in coating thickness, the static friction coefficient first increases to its maximum value at a certain coating thickness, thereafter decreases, and eventually levels off. The effect of the normal load and material properties on this behavior is discussed. Finally, a model for the static friction coefficient as a function of the coating thickness is provided for a wide range of material properties and normal loading.
文摘对销轴连接的铸钢件承载能力进行试验研究。试验选择100、150、182 mm三种不同厚度的铸钢试件,最大加载拉力为8 000 k N。结果表明:在拉力作用下,铸钢试件发生了不同程度的塑性变形,塑性区面积随试件厚度的增大而显著减小,塑性开展大致呈剪切型发展。铸钢件与销轴直接承压接触的部位,由于应力集中很快达到屈服;接触变形导致区域内应力重分布,部分测点应变减小,甚至出现拉压应变反转的现象。与有限元分析结果对比表明,偏心受力会使铸钢件与销轴接触部位在加载初期产生较大应力集中。将承载力的试验结果与采用各国规范设计公式计算的结果进行对比,建议承载力计算公式中设计强度提高系数取为1.2。
