PRODUCTION OF HOT ROLLED MATERIAL CONSISTING OF ALPHA+BETA TYPE TITANIUM ALLOY

摘要

PURPOSE:To produce a hot rolled material of an alpha+beta type titanium alloy having uniformly dispersed fine alpha grains and high quality by subjecting an alpha-beta type titanium alloy to a heat treatment under adequate conditions and to working at a high ratio in an adequate temp. range then annealing the alloy in a specific temp. region. CONSTITUTION:The alpha+beta type titanium alloy is heated to the temp. of beta-transus or above to suppress the precipitation of the alpha-phase. The alloy is then cooled at <=15 deg.C/sec average cooling rate from the beta-transus down to 800 deg.C to prevent the formation of martensite. The alloy is worked at least at >=70% in the temp. region from the beta-transus down to 650 deg.C within 10min upon passage of the beta-transus in the above-mentioned cooling process so that the fine alpha grains are uniformly precipitated. The alloy after the working is then annealed in a 600-800 deg.C range by self-annealing etc. The hot rolled material consisting of the alpha+beta type titanium alloy having excellent ductility and high quality is thus obtd. at a high yield and low cost.