【作者】 王明智； 吴建军；

【Author】 Mingzhi Wang;Jianjun Wu;School of Mechanical Engineering,Northwestern Polytechnical University;

【机构】 西北工业大学机电学院；

【摘要】 本文研究提出了一种改进的扩展孔洞模型(ECM),用于依据球形压痕载荷位移曲线响应预测各向异性板料的单轴流动应力应变曲线。在经典ECM理论模型基础上,将压头底部静水压力区进行分块,以考虑由于板料面内塑性异性所导致的压头底部静水压力区应力分布沿着不同方向上的差异。基于此,将压头底部接触压力与静水压力区压力及板料面内不同方向上的单轴流动应力相关联,从而建立起修正的塑性约束因子表达式。采用TC1、TC3和TA2三种各向异性钛合金板料对所提出理论模型进行了有效性验证。结果表明,通过所提出理论模型预测的应力应变曲线与通过单轴拉伸实验获得的应力应变曲线吻合良好。更多还原

【Abstract】 In this paper,an improved expanding cavity model(ECM) is proposed to predict the flowing stress strain curves of anisotropic materials based on the indentation load-displacement curve. In the classic ECM,The cavity in the new model was assumed to contain several sections to take account of the influence of material anisotropy on the stress field distribution in the loading process. We correlated the indentation contact pressure and hydraulic pressure with the anisotropic material flow stress in different directions and presented a modified formula to calculate the representative stress strain curves. The effectiveness of this new model was proved through the application to three outstanding anisotropic materials.更多还原