Abstract
A hot stamping process of a titanium alloy sheet using resistance heating was developed to improve the productivity. As the heating temperature increased, the bending load decreased and the titanium alloy sheet was successfully formed at elevated temperatures. As the heating temperature increased, the springback of the bent sheet decreased. Although needle-shaped martensite appeared at a heating temperature of 1050°C, the microstructure at a heating temperature of 880°C was similar to the as-received sheet. When the heating temperature increased to 880°C, the hardness increased to 370 HV20. It was found that the hot hat-shaped bending of the titanium alloy sheet using the resistance heating was effective in improving the productivity.
Keywords
Titanium alloy sheet, Ti-6Al-4V, hot stamping, resistance heating, springback.
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