Strength and Temperature Increase of -Ti Alloy during Quasi-Static and Impact Compressive Deformation
Hidetoshi KOBAYASHI, Fuji OKADA, Klinya Ogawa, Keitaro HORIKAWA and Keiko WATANABE
Abstract:Titanium alloy is one of the typical aerospace structural materials because of its lightness, high specific strength, and high corrosion resistance. However, it has extremely low thermal conductivity, too. This causes relatively high temperature rise due to the heat converted from plastic work, especially under impact loading. In this study, a series of compression tests for -titanium alloy in the wide ranges of testing temperature ( 77K ` 673K ) and strain rate ( 3.3~10-4 ` 103 s-1 ) was carried out to investigate the effect of the heat generation on the mechanical properties. The temperature rise of the specimen during impact compression tests was measured by an infrared radiation thermometer with a photoconductive element. The conversion ratio of plastic work into heat h was also examined at temperatures of 201K ` 473K. The principal results obtained are as follows: The temperature rise of specimen during plastic deformation at 201 K is greater than that observed at room temperature (298 K) and at 473 K. The conversion ratio h is not necessarily to be constant, i.e. h is less than 0.1 in the early plastic deformation and gradually increases up to around 0.7 with the increase of plastic deformation at 298 K. The increase of h at lower temperature is more drastic. Key Words:-titanium alloy, Impact, Compression, Photoconductive element, Temperature rise @