In the field of titanium alloy material preparation, a preparation method of high strength and high plasticity titanium alloy wire is disclosed, including: multi-fire forging of melted titanium alloy ingot; Multiple rolling is carried out at the temperature of 80℃ ~ 150℃ above the Tβ phase transition temperature. The temperature of 760℃ ~ 820℃ was heated online, and then the multi-pass hot drawing was carried out. The temperature of the multi-pass hot drawing was decreased successively, and the deformation amount of the multi-pass hot drawing was 7-15% when the temperature of the multi-pass hot drawing was decreased by 0 ~ 10℃ each time. Titanium alloy wire is made by peeling and stress - relieving annealing. The invention has prepared φ3.0 ~ φ7.0 mm titanium alloy wire with uniform structure, high tensile strength at room temperature, good plasticity, simple production process and low production cost.
At present, high strength titanium alloys are widely used as structural or connecting materials for all kinds of large aircraft or high-speed aircraft in the world. The performance of high strength titanium alloy has become one of the important indexes to evaluate the design and manufacture of aircraft. The most commonly used titanium alloy fasteners are TC4, TC16, TB2, TB3, TB5, TB8, etc. TC4 titanium alloy has good strength and fatigue properties, stable process, low cost, is the most widely used titanium fastener material. However, due to the poor ductility and hardenability of TC4 at room temperature, it cannot meet the requirements of cold heading and high strength, and the cost of hot forming is large. The existing TC4 titanium alloy wire has room temperature tensile strength Rm≥1100 and elongation A≥ 10%, which cannot meet the urgent demand for high-strength and ultra-high strength fasteners in the aerospace field. TC16 titanium alloy is mainly used in the manufacture of aerospace fasteners, with the required room temperature tensile strength Rm≥1030 and elongation A≥ 12%. It can realize cold machining molding under annealing condition, which can reduce the forming cost of fasteners, but its strength and fatigue properties are not as good as those of TC4 titanium alloy. TB2 and TB3 titanium alloys are β-type titanium alloys independently developed in China, and their required room temperature tensile strengths are Rm≥1100. TB5 titanium alloy requires room temperature tensile strength Rm≥1000, elongation A≥ 10%, TB8 titanium alloy requires room temperature tensile strength Rm≥1250, elongation A≥ 8%. The above alloys are mainly used for rivets, bolts and screws of aviation and aerospace vehicles, but the strength of these materials is below 1300MPa, which does not meet the requirements of ultra-high strength titanium alloys.
