Drawing process of titanium and titanium alloy wire
Titanium wire and titanium wire drawing
Pulling the wire rod or wire blank from the die hole of the wire drawing die under the action of drawing force to produce a metal plastic working process of a small-section steel wire or a non-ferrous metal wire. Wires of various cross-sectional shapes and sizes of various metals and alloys can be produced by drawing. The drawn wire has an accurate size, a smooth surface, and the drawing apparatus and the mold are simple and easy to manufacture. Deformation index of the drawing process The length of the cross section of the titanium wire is increased during the drawing process, and the cross-sectional area and length of the wire before and after the drawing are represented by F, F, L and L, respectively. The condition of the drawing process is usually expressed as: the ratio K of the sum is called the safety factor of the drawing process. When drawing an ultra-fine wire with a wire diameter of less than 0.05 mm, it is difficult to wear the mold. In order to improve the stability of the drawing process, reduce the number of times of pulling and punching, and improve the drawing production efficiency, the safety factor K value may be greater than 2.0. The reference values for the safety factor K of the drawing process for drawing different wire diameters are as follows:
The type is drawn according to the temperature of the metal at the time of drawing, the drawing below the recrystallization temperature is cold drawing, the drawing above the recrystallization temperature is hot drawing, and the drawing above the room temperature lower than the recrystallization temperature is warm drawing. Cold drawing is the most common drawing method used in wire and wire production. When hot drawing, the wire is heated before entering the die hole, and is mainly used for drawing of high melting point metals such as tungsten, molybdenum and the like. At the time of warm drawing, the wire also needs to be heated by the heater to a specified temperature to enter the die hole for drawing, and is mainly used for drawing zinc wire, hard-deformed alloy wire such as high-speed steel wire and bearing wire. According to the number of molds that the wire passes at the same time during the drawing process, the drawing by one mold is a single pass drawing, and the drawing through several (2-25) successively successively is a multi-pass continuous drawing. The single-pass drawing has low line speed, low productivity and low labor productivity, and is often used for drawing large diameters, low plasticity, and shaped wires and wires. Multi-pass drawing has high line speed, high degree of mechanization automation, high productivity and high labor productivity, and is the main method for wire and wire production. It is divided into non-sliding continuous drawing and sliding continuous drawing. According to the state of the lubricant used in the drawing, the liquid lubricant is wet drawn, and the solid lubricant is dry drawn. According to the cross-sectional shape of the drawn wire, there is a circular wire drawing and a profiled wire drawing. According to the tensile force acting on the drawn wire, there is a positive pulling force and a pulling force pulling. There are also special pulls, such as roller die drawing.
Process characteristics The stress state of wire drawing is the three-way principal stress state of the two-direction compressive stress and the tensile stress. Compared with the principal stress state of the three-direction compressive stress, the drawn wire is more likely to achieve plastic deformation. status. The deformation state of the drawing is a three-way main deformation state in which the two-direction compression deformation is stretched and deformed, which is disadvantageous for exerting the plasticity of the metal material, and is relatively easy to generate and expose surface defects. The amount of deformation of the wire during the drawing process is limited by the safety factor. When the amount of deformation of the ball is small, the number of drawing passes is large. Therefore, multi-pass continuous high-speed drawing is often used in the production of wire.