Spring-back and spring-go behaviors in bending of thick plates of high-strength steel at elevated temperature

• We simulate spring-back and spring-go of a thick high-strength steel plate.
• The effect of temperature and corner radius of punch was investigated.
• We construct the prediction model of spring-go.

Recently, the usage of thick plate is being increased to replace the forged parts for reducing the weight, forming load as well as improving the tool life in the automotive industry. In this study, a numerical simulation was carried out to find the process conditions which affect the product quality by examining the U-channel shape and the forming capabilities for thick high-strength steel plates. The steel plate used was composed of Nb 0.05%–Ti 0.01%–V 0.07% micro-alloyed high-strength steel with a 580 MPa strength at room temperature. The effect of forming temperature and corner radius of punch on spring-go behavior was investigated, and mechanism of spring-go based on through-thickness stress was found during the bending of thick plate at the elevated temperature. Based on the simulation results, a prediction model of spring-go was constructed, and compensation method of the tool to improve the dimensional accuracy of bent part was suggested.

The amount of spring-go with forming temperature and corner radius of punch and mean stress distribution along inner and outer surfaces.Figure optionsDownload as PowerPoint slide