钨合金丝材无模拉拔成形温度场及流动应力梯度

Temperature Field and Yield Stress Grads during Wire Die-Less Drawing of Tungsten Alloy

简述了目前钨合金丝材加工技术特点及变形过程存在的技术问题,分析了采用无模拉拔成形技术加工钨合金丝材的可行性及变形机制。通过实验研究,确定了钨合金丝材无模拉拔成形的温度场模型和流动应力模型,确定了钨合金丝材无模拉拔成形变形区温度梯度及流动应力梯度。研究结果表明,钨合金丝材无模拉拔成形时,当Z≤ZM时变形区温度场沿轴向呈线性分布;当Z>ZM时变形区温度场沿轴向呈非线性分布,温度梯度沿轴向呈线性分布;变形区流动应力场沿轴向接近线性分布,流动应力梯度接近于常数。

The deformation characteristics,the technological problems, the deformation mechanism and feasibility of wire die-less drawing of tungsten alloy were analyzed. The model of temperature field and flow stress were determined. The grads model of temperature field and flow stress were studied by experiment and theory analysis. Results showed that the temperature field of deformation presented linear law along axes when Z≤Zm during wire die-less drawing of tungsten alloy, and the temperature field of deformation presented non-linear law along axes when Z 〉 ZM, temperature grads and yield stress presented linear law along axes, and yield stress grads approached constant along axes.