半固态金属触变塑性成形上限法  

Upper bound method of thixotropic plastic forming process for semi-solid metal

作　　者：闫洪[1] 夏巨谌[2] 

机构地区：[1]南昌大学机电学院,南昌330029 [2]华中科技大学模具技术国家重点实验室,武汉430074

出　　处：《塑性工程学报》2005年第5期63-65,共3页Journal of Plasticity Engineering

基　　金：国家自然科学基金项目(50465003);江西省自然科学基金项目(0350005);华中科技大学塑性成形及模具技术国家重点实验室基金项目(04-8)

摘　　要：在高固相率时,半固态金属的力学模型可简化为连续多孔体力学模型。针对半固态金属触变塑性成形的特点,本文发展了上限法理论在半固态金属触变塑性成形分析中的应用。提出速度间断值不仅要包括切向分量,还要包括法向分量。速度间断的法向分量是由金属通过速度不连续面时,材料固相率的变化而引起的。由此建立了半固态金属触变塑性成形的上限分析模型和理论方法,导出了上限功率的计算公式。为在实际触变塑性成形工艺分析中的进一步应用奠定了理论基础。The mechanical model of the semi-solid materials is treated as that of the continuous porous materials in the high solid volume fraction. The development of upper bound theory of thixotropic plastic forming process for semi-solid metal was done. There are velocity discontinuities not only in the tangential component but also in normal components for the kinematieally admissible displacement increment filed. The latter one was responsible for a change in solid volume fraction when the material passes the discontinuity. An upper bound analytical model and theoretical method of thixotropic plastic forming process for semi-solid metal has been proposed. The calculating formulas of deformed power were derived. It is theoretical basement to apply further for practice thixotropic plastic forming technology analysis.

关 键 词：半固态金属 触变塑性成形 连续多孔体 上限法 

分 类 号：TG146.2[一般工业技术—材料科学与工程]