Abstract
Pure titanium has high specific strength and high corrosion resistance, and is also lighter than stainless steel in corrosion resistance. It has been widely used together with titanium alloys for a long time in chemical plants and heat exchangers. Pure titanium, which is widely used as a product, is JIS type 2. It is expected that JIS type 2, which has high strength while maintaining purity, will be used. In general, cold working and heat treatment methods are used to increase the strength. In the present study, the material properties of pure titanium were improved by a combination of cold rolling and heat treatment. Mechanical properties were examined by tensile testing. The test material was a commercially available pure titanium JIS 2 sheet. The initial thickness of the sheet was 1 to 5 mm. The thickness of the tensile test workpiece was 0.4 to 0.7 mm. The rolling reduction ranged from 30 to 92 %. An increase in tensile strength was obtained in the heat treatment from 400 to 500 oC while maintaining the ductility. In particular, the tensile strength was greatly improved under the condition of 70 % of rolling reduction and heat treatment temperature of 400 oC. The effect of strain rate on mechanical properties showed little effect.
