线材无模拉拔成形力数学模型研究

Study on Mathematical Model of Forming Force During Wire Dieless Drawing

采用上限法确定了钨合金线材无模拉拔成形速度场及力能参数物理模型.分析了钨合金线材无模拉拔成形的变形模型、速度场以及力能参数的影响因素及影响规律,无模成形力能参数的影响因素主要有冷热源间距、断面减缩率、变形温度、拉伸速度、冷热源移动速度以及材料种类等,为无模拉拔成形工艺工业化应用奠定基础.

Dieless drawing is a newly development flexible metal forming technique without dies which is only according to the character that the metal flow stress varies as deformation temperature. On the basis of analysis in deformation mechanism and velocity field of wire dieless drawing, drawing force and velocity field are studied theoretically, and the formulas have been determined by means of Up Boundary method. It has been found that the theoretical calculating results of dieless drawing force are very approximate to that of experiment. It is also found that forming force has relation to deformation width, sectional reduction ratio, deformation temperature, forming speed, heating-cooling apparatus moving speed.