TC16 and TC4 titanium alloy wires for fasteners

TC16 and TC4 titanium alloys developed by Institute of metal research, Chinese Academy of Sciences, are the main materials used in the manufacture of aircraft fasteners. According to the domestic TC16 titanium alloy wire in shear strength to meet the requirements of problem under the condition of low plasticity is difficult to realize the cold heading through the system research, TC16 wire "- tensile strength of shear strength for cold heading process performance of the" three key properties of the matching relationship between the proposed shear ratio criterion, and to determine the organization of fine grain basket is to meet the cold heading wire the best organization of comprehensive performance of the material requirements; and then design thermomechanical processing, fine grain and uniform distribution of the lamellar structure;

In addition, the impurity element O as the micro alloying strengthening elements to use, under the premise of ensuring the plasticity and process of, to increase the strength level of wire and fasteners; finally developed the first domestic TC16 titanium alloy cold heading wire qualified. Aiming at the problem of low, domestic TC4 alloy wire strength uneven microstructure, poor stability, the impurity element O as the micro alloying strengthening elements to use, and use of micro alloying elements Fe TC4 significantly improves the hardenability of the alloy, solves the TC4 fasteners hardenability, insufficient strength and other problems the research and development; tandem Y type three roller rolling line with independent intellectual property rights, control rolling technology combined with optimization, TC4 annealing wire uniform and fine equiaxed microstructure were obtained, and the effective control of the wire horizontal texture, greatly improves the process performance of wire hot upsetting, and greatly improved the uniformity and performance of wire organization consistency and stability.