颤振冷挤压降载机理与仿真研究

针对金属冷挤压成形过程中金属变形抗力大、设备吨位高而普遍振动形式降载效果不理想的问题,将颤振激励技术引入金属冷挤压成形过程中。从表面效应角度分析了颤振激励下的金属冷挤压成形过程中摩擦力的变化规律,阐明了颤振降载的基本原理。以万向节轴套零件为例,分别讨论分析了传统冷挤压模式和颤振激励冷挤压模式下的挤压力数学模型,从理论上说明了颤振冷挤压的降载机理,进一步应用Deform-3D软件建立了其有限元分析模型,对万向节轴套零件进行了受载和模具寿命分析。仿真实验结果表明,在100 Hz频率0.03 mm振幅的周期性颤振激励下,万向节轴套零件的冷挤压过程最大成形压力下降8.3%,最终成形压力下降10.1%;冲头单次最大磨损量下降,但凹模单次最大磨损量有一定程度的增加。

Load shedding principle of flutter cold extrusion and its simulation

Aiming at the problem of high resistance to deformation and large tonnage equipment, while the common vibration forms have unsatisfied load shedding, flutter stimulation is imported into the metal cold extrusion process will contribute to the reducing of the forming resistance, from the view of a surface effect, the friction variation during the metal cold extrusion process under flutter stimulation was analyzed. The basical principle of vibration load shedding was illuminated. The basical principle of load shedding under flutter stimulation was illuminated. Taken the universal-joint sleeve as the example, Deform-3D software was used for the establishment of the finite element analytical model. The simulation results implied that the maximum forming resistance of the universal-joint sleeve cold extrusion reduces 8.3%, and the final forming resistance reduces 10.1% under the periodic flutter stimulation of frequency 100 Hz and amplitude 0.03 mm. The wear extent of the single punch also reduced,while that of the die increased.