Transactions of Materials and Heat Treatment

Title：Analysis and improvement on punch fracture of inner spline in backward extrusion process

Authors： Huang Juan Xiao Tiezhong Hu Xiaoqing

Unit： Sichuan Engineering Technical College

KeyWords： combination punch backward extrusion fracture

ClassificationCode：TG391.9

year,vol(issue):pagenumber：2015,40(8):87-90

Abstract：

For the problem of the punch fracture in backward extrusion process of inner spline, the failure analysis of the punch was conducted. The analysis result shows that the extrusion force produced in the forming of inner spline is big and the stress concentration appears in the transitional section of ladder-shape punch, where the equivalent stress of 3800 MPa exceeds the materials ASSAB88 bending strength of 3500 MPa, so the brittle fracture is generated in the transitional section. In order to avoid the early failure of punch, the combination punch was adopted. Simulation result shows that the combination punch works without stress concentration and the equivalent stress of its work area is 3150 MPa. The production practice shows that the combination punch can effectively avoid the early failure of punch.

Funds：

垫江县汽摩配套产业发展分析与研究（CSTC2013 JCCXB60001）

黄娟（1987-），女，硕士研究生，助教

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