论文部分内容阅读
研究了硅模具的破碎原因,利用自主研制的非晶合金超塑性微成形试验机,对Zr65Cu17.5Ni10Al7.5非晶合金进行了大量超塑性微小零件成形实验.随机抽取了125组实验结果进行了统计分析,结果表明:90.70%的硅模具发生破碎时应力值低于40MPa,其中,46.51%的破碎行为发生在瞬间载荷为20 MPa、应变为0.1附近区域;39.53%的破碎行为发生在瞬间载荷为25MPa、应变为0.5附近区域.这两个区域恰好处于微成形各过渡阶段,材料的流动方向和速率发生明显改变,表明模具受力方向突变和局部应力增大是导致破碎的主要原因.结合DEFORM 3D仿真分析,得出利用夹具、增大坯料尺寸、增大模具尺寸可减少硅模具破碎几率,增加工艺可靠性.
The reasons for the breakage of the silicon mold were studied, and a large number of experiments on forming the superplastic micro-parts of Zr65Cu17.5Ni10Al7.5 amorphous alloy were carried out by using the self-developed amorphous alloy superplasticity micro-forming testing machine.The experimental results of 125 groups were randomly selected The results show that the stress value of 90.70% silicon molds crushing is lower than 40MPa, among them, 46.51% crushing behaviors occur at instant load of 20 MPa and strain of 0.1, while the crushing of 39.53% Is 25MPa and the strain is near 0.5.These two regions happen to be in the transitional stages of micro-forming, and the flow direction and velocity of the material change obviously, which indicates that the sudden change of stress direction and local stress of the die are the main reasons leading to the breakage. DEFORM 3D simulation analysis shows that the use of fixtures, increasing the blank size, increase the size of the mold can reduce the probability of broken silicon mold, increase process reliability.