论文部分内容阅读
因工程设计中挤压力的计算依赖于经验公式,误差较大且不利于优化设计,基于经典塑性理论,运用数学方法探索更准确方便的挤压力的求解模型。以滑移线场为理论平台,以杯形件反挤压过程为研究对象,分析不同压缩比的系列滑移线特征并叠加得到代表滑移线场。在求解应力场及变形力的基础上,通过曲线拟合方法研究滑移线场参数与模具几何参数的解析关系,从而建立变形物理参数与几何参数的数值分析模型。该数值分析模型所得解析解比滑移线场数值解具有更明显的物理意义,在知道变形几何参数的前提下,可方便求解挤压力。最后通过实测挤压力、并结合经验公式进行验证。结果表明数值分析模型计算结果较准确,并可作为目标函数实现工艺优化设计。
Because of the engineering design of the calculation of the extrusion pressure relies on the empirical formula, the error is large and not conducive to optimal design, based on the classical plastic theory, the use of mathematical methods to explore more accurate and convenient solution to the extrusion pressure model. Taking the slip line field as the theoretical platform and the cup extrusion anti-extrusion process as the research object, the characteristics of series slip lines with different compression ratios are analyzed and the slip line field is superposed. Based on the solution of stress field and deformation force, the analytical relationship between the slip line field parameters and the geometric parameters of the mold is studied by the curve fitting method, and the numerical analysis model of the deformation physical parameters and the geometric parameters is established. The analytical solution obtained by the numerical analysis model has more obvious physical meaning than the numerical solution of slip line field. Under the premise of knowing the deformation geometric parameters, the squeezing pressure can be easily solved. Finally, the squeezing force was measured and verified by empirical formula. The results show that the numerical analysis model is more accurate and can be used as an objective function to optimize process design.