Common Defects And Coping Strategies In The Preparation Process Of Titanium Wire

Because of its excellent corrosion resistance, high strength and good biocompatibility, titanium wire is widely used in aerospace, medical equipment, chemical industry and other fields. However, in the preparation process of titanium wire, due to the influence of various factors such as material properties, process parameter control and equipment status, various defects are prone to occur, affecting product quality and performance.

1. Surface Scratches And Abrasions

Cause: Surface scratches and abrasions are more common surface defects in the preparation of titanium wire, mainly due to incomplete surface treatment, insufficient lubrication, metal surface adhesion to sand or tool surface defects. These factors rub against the surface of the titanium wire during drawing or processing, causing damage.

Solution: The surface treatment should be carried out in strict accordance with the operating procedures to ensure that the treatment is thorough and uniform; choose a suitable lubricant and ensure that the lubrication is sufficient and evenly covers the surface of the titanium wire; keep the lubricant clean to avoid impurities mixing; regularly inspect and repair the tools to ensure that the surface of the tools is smooth and free of defects.

2. The Size Is Too Poor

Cause: The poor size is usually related to the unqualified size of the mold, excessive corrosion or local excessive corrosion during pickling. The deviation of the mold size directly affects the diameter of the titanium wire, while improper pickling may cause uneven surface corrosion of the titanium wire, which in turn affects the dimensional accuracy.

Solution: Before stretching, the size of the mold should be carefully checked to ensure that it meets the requirements of technical conditions; during the pickling process, the material needs to be continuously flipped so that all parts of the titanium wire are evenly acidified, and the diameter of the wire should be checked at any time, and the pickling parameters should be adjusted in time to avoid excessive corrosion.

3. Surface oxidation

Cause: Surface oxidation is a common problem in the annealing or rewinding process of titanium wire, mainly due to insufficient vacuum during annealing, excessive baking temperature or surface adhesion during rewinding. Oxidation not only affects the appearance of titanium wire, but may also reduce its corrosion resistance.

Solution: Ensure that the vacuum degree of the annealing furnace meets the requirements to reduce oxygen contact; control the baking temperature below 200℃ to avoid the reaction of titanium wire with oxygen at high temperatures; during the rewinding process, keep the surface of the wire clean to avoid sticking.

4. Internal Cracking

Cause: Internal cracking is a serious defect inside the titanium wire, usually caused by metallurgical defects caused by refractory metal elements in the titanium alloy material, or caused by rapid cooling and uneven temperature during the drawing process. Internal cracking will significantly reduce the mechanical properties of titanium wire.

Solution: The control of material composition should be strengthened to ensure that the content of each element in the titanium alloy meets the standards; the forging process should be optimized to avoid rapid cooling and uneven temperature, and measures such as preheating and heat preservation can be used to make the titanium wire evenly heated during the drawing process.

5. Longitudinal Cracking

Cause: Longitudinal cracking mostly occurs at the edges and corners of the blank, mainly due to the fast cooling speed or the stress concentration of high-temperature titanium alloy when the water is cooled. Cracking will destroy the continuity of the titanium wire and affect its performance.

Solution: The chamfering temperature should be controlled to avoid excessive cooling at the edges and corners of the blank; when the high-temperature titanium alloy is water-cooled, a slow-cooling process is used to reduce stress concentration; the cracked titanium wire should be removed in time to avoid flowing into the next process.

6. Dot-Like Defects

Cause: Dot-like defects usually originate from metallurgical defects on the end face of pure titanium bars, such as holes, component segregation, etc. These defects may expand into larger defects during the drawing process, affecting the quality of the titanium wire.

Solution: The smelting process should be optimized, the smelting temperature and time should be increased, and the homogenization of the composition should be promoted; the control of the uniformity of the composition should be strengthened to avoid local defects; the titanium bars with dot-like defects should be screened to avoid being used in the preparation of titanium wire.

7. Hydrogen-Induced Cracks

Cause: Hydrogen-induced cracks are cracks caused by excessive hydrogen content during welding or processing of titanium wire. Hydrogen may come from factors such as surface pollution of the base material or welding wire and high environmental humidity. Hydrogen-induced cracks will significantly reduce the toughness and strength of titanium wire.

Solution: It should be strictly cleaned before welding, and mechanical or chemical methods should be used to remove oil stains, oxides and other impurities from the surface of the base material and the welding wire; control the ambient humidity to avoid welding or processing in a humid environment; use high-purity protective gas to reduce the mixing of hydrogen.

Defect control in the preparation process of titanium wire is the key to ensuring product quality. By optimizing process parameters, strengthening material quality control and environmental management, the occurrence of common defects such as surface scratches, dimensional abnormalities, surface oxidation, internal cracking, longitudinal cracking, dot-like defects and hydrogen-induced cracks can be effectively reduced. In actual production, measures should be flexibly adjusted according to specific production conditions, experience should be continuously summarized, the level of titanium wire preparation should be improved, and the demand for high-quality titanium wire in various fields should be met.