工艺参数对楔横轧特大型轧件内部应力影响分析

INFLUENCE OF TECHNOLOGICAL PARAMETERS ON INNER STRESS OF EXTRA-LARGE ROLLING PIECE DURING CROSS WEDGE ROLLING

楔横轧成形特大型轧件为复杂的三维变形 ,其内部应力变化规律复杂 ,至今缺乏深入研究与本质理解 ,严重影响楔横轧的应用与发展。采用有限元先进数值方法模拟楔横轧特大型轧件成形过程 ,详细分析成形过程中轧件内部中心点的应力变化规律 ,阐明成形角、展宽角和断面收缩率三个主要工艺参数对特大型轧件内部应力的影响关系 ,为合理选取楔横轧特大型轧件模具工艺参数、开发设计特大型楔横轧机提供重要的理论依据。

Shaping up extra-large rolling piece by cross wedge rolling method is a kind of complicated 3-D deformation. Up to now, the change of inner stress of rolling piece during cross wedge rolling has not been understood properly. So the application and development of cross wedge rolling have been baffled severely. With advanced FEM, the cross wedge rolling of extra large rolling piece is simulated. Base on it, the change of stress in the center of rolling piece during cross wedge rolling is analyzed in detail. In the meantime, the influence of three main parameters, namely shape angle, spread angle and shrinkage ratio of section, on inner stress is clarified. The result provides important theoretical basis for determining die parameters and designing extra-large cross wedge mill.