HPb59-1剪切销镦粗过程一致性控制研究

Research on Consistency Control of Upsetting Process for HPb59-1 Shear Pins

摘要: 为确定Y2状态的HPb59-1剪切销液压镦粗的最优工艺参数，首先通过拉伸破坏试验获取HPb59-1铜棒原材料主要力学性能指标；随后结合仿真分析、试验件尺寸和理论计算结果，设计并开展液压镦粗压力梯度试验，通过金相组织分析探究镦粗前后材料微观结构的变化规律，同时结合产品拉断力测试数据，最终确定合理的液压镦粗压力参数。研究表明：镦粗过程中材料金相组织发生显著变化，镦粗后轴向截面的α相条带宽度增加、长度伸长，β相沿带状边界更连续，变形特征更加显著；在镦粗过程中，剪切销材料内部结构在塑性变形作用下发生了重构，这种组织结构的演变直接导致了其剪切性能的显著增强；与传统手工镦粗相比，液压镦粗工艺可有效提升产品拉断力的一致性；对于Y2状态的HPb59-1剪切销，当液压镦粗压强控制在707.4 MPa~1061 MPa范围内时，产品拉断力散差较小，综合性能表现稳定，可满足实际生产要求。

Abstract: To determine the optimal hydraulic upsetting process parameters for HPb59-1 shear pins in the Y2 state, the primary mechanical property indicators of raw HPb59-1 brass bars were first obtained via tensile fracture tests. Subsequently, gradient hydraulic upsetting pressure tests were designed and implemented, combined with simulation analysis, specimen dimensions, and theoretical calculation results. The evolution law of material microstructure before and after upsetting was investigated through metallographic analysis, and reasonable hydraulic upsetting pressure parameters were finally determined in combination with product breaking force test data. The results show that obvious changes occur in the metallographic structure of materials during upsetting. After upsetting, the width and length of α-phase bands on axial cross-sections increase, the β-phase distributes more continuously along band boundaries, and the deformation characteristics become more prominent. The internal microstructure of shear pin materials is reconstructed under plastic deformation, and such structural evolution directly leads to a remarkable improvement in shear performance. Compared with the traditional manual upsetting method, the hydraulic upsetting process can effectively improve the consistency of the product breaking force. For HPb59-1 shear pins in Y2 state, when the hydraulic upsetting pressure is controlled within the range of 707.4 MPa to 1061 MPa, the breaking force dispersion of finished products is low with stable comprehensive performance, which can fully meet the requirements of practical industrial production.