Scholarlink

<p>The traditional single-layer hot stamping process has a significant temperature drop during sheet metal transfer and forming, and the springback of the formed parts is relatively large. The new hot stamping forming process that adopts a triple-layer plate stacking method can effectively reduce the springback after forming. In order to predict the springback behavior of Ti-6Al-4V alloy after hot stamping of triple-layer plates, this paper studies the stress relaxation (SR) behaviors and microstructure evolution of Ti-6Al-4V alloys were investigated at different temperatures (500&#xa0;°C, 550&#xa0;°C, 600&#xa0;°C and 650&#xa0;°C) and pre-strains (2%, 4% and 8%). The SR constitutive model was also established and embedded in the simulation software to analysis the sheet springback. The prediction accuracy of the simulation model was verified by hot forming experiments. The results show that high temperature and high pre-strain jointly affect the SR process. The initial relaxation stress (IRS) difference with a pre-strain of 2% and 8% decreased from 130&#xa0;MPa at 500&#xa0;°C to 2&#xa0;MPa at 650&#xa0;°C, and the stress relaxation limit (SRL) has been reduced from 204&#xa0;MPa to 4.1&#xa0;MPa. By observing the microstructure of the SR samples, it was found that the content of low-angle grain boundaries (LAGBs 2°–15°) decreased from 57.3% to 49.1% with the increase of temperature. The dislocation slip and climb are the main mechanism of SR at low temperature, and mechanism of SR becomes grain boundary slip and diffusion creep under high temperature conditions. The springback angle increases with the die radius and sheet temperature increasing. In the triple-layer sheet hot stamping process, U-shaped parts experienced stress relaxation behavior during the quenching process. The springback angle decreases by 82.8% increasing by the sheet temperature. Compared with the experimental results, the simulation prediction model has a higher prediction accuracy.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Stress relaxation behavior and springback prediction of Ti-6Al-4V alloy under triple-layer-sheet hot stamping condition

  • 期刊论文

  • 发表日期：

    2026年2月9日

查看全文
  • Lida Yu,
  • Xiaoming Yang,
  • Shengqiang Liu,
  • Xiaomin Huang,
  • Baoyu Wang,
  • Hongchao Ji

摘要

The traditional single-layer hot stamping process has a significant temperature drop during sheet metal transfer and forming, and the springback of the formed parts is relatively large. The new hot stamping forming process that adopts a triple-layer plate stacking method can effectively reduce the springback after forming. In order to predict the springback behavior of Ti-6Al-4V alloy after hot stamping of triple-layer plates, this paper studies the stress relaxation (SR) behaviors and microstructure evolution of Ti-6Al-4V alloys were investigated at different temperatures (500 °C, 550 °C, 600 °C and 650 °C) and pre-strains (2%, 4% and 8%). The SR constitutive model was also established and embedded in the simulation software to analysis the sheet springback. The prediction accuracy of the simulation model was verified by hot forming experiments. The results show that high temperature and high pre-strain jointly affect the SR process. The initial relaxation stress (IRS) difference with a pre-strain of 2% and 8% decreased from 130 MPa at 500 °C to 2 MPa at 650 °C, and the stress relaxation limit (SRL) has been reduced from 204 MPa to 4.1 MPa. By observing the microstructure of the SR samples, it was found that the content of low-angle grain boundaries (LAGBs 2°–15°) decreased from 57.3% to 49.1% with the increase of temperature. The dislocation slip and climb are the main mechanism of SR at low temperature, and mechanism of SR becomes grain boundary slip and diffusion creep under high temperature conditions. The springback angle increases with the die radius and sheet temperature increasing. In the triple-layer sheet hot stamping process, U-shaped parts experienced stress relaxation behavior during the quenching process. The springback angle decreases by 82.8% increasing by the sheet temperature. Compared with the experimental results, the simulation prediction model has a higher prediction accuracy.