Distortion Reduction for Curved Hat Channel of AHSS(DP980)

• Main Authors: Kai-Chieh Hsu, 許凱傑
• Other Authors: Kuan-Ming Li
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/5cvj99

碩士 === 國立臺灣大學 === 機械工程學研究所 === 105 === As the global warming becomes worse and the environmental consciousness rises, AHSS has been widely used as the material of automobile structural parts. However, as the strength of steels increases, stamping defects such as sidewall curl and distortion become worse. This study investigates the distortion in sheet metal forming. A-pillar is an automobile structural part. Among all automobile structural parts, A-pillar is most likely to be distorted. This study induces the geometric parameters of A-pillar. This study also establishes a model for curved hat channel which has similar geometry with the A-pillar and uses PAM-STAMP to simulate the stamping process with the established model. This study investigates the formability influenced by different geometric parameters. The result can be the reference for A-pillar design. Next, this study simulates the distortion defects influenced by different geometric parameters. By studying the stress distribution on different cases, the mechanism of distortion can be discussed. Furthermore, strategies, like drawbead and die compensation, are used to reduce distortion. This study proposes two die compensation methods for distortion which solve the problem that punch have no space to stamp after compensation. The result in reducing distortion is significant, from 9 degrees to 1.5 degrees. At last, a curved hat channel die has been designed.