How does the multi-pass drawing process of titanium wire create a precise string in the medical and industrial fields?

The preparation of titanium wire begins with the smelting and forging of titanium and titanium alloy billets, and the key to its performance lies in the multi-pass drawing process. This process uses a die drawing with continuous diameter reduction to gradually reduce the diameter of the titanium wire from several millimeters to the micron level. Each drawing is accompanied by the rearrangement of the grains inside the material and the elimination of defects.

1. Grain refinement and texture control
During the drawing process, the titanium wire undergoes severe plastic deformation, and the original coarse grains are broken into slender fibrous structures. This evolution of microtexture not only improves the strength of the material, but also gives it unique anisotropic properties. For example, the 0.20-0.28mm anastomotic titanium wire commonly used in the medical field has a directional arrangement of grains along the axial direction, which can significantly improve the flexibility and fatigue resistance of the suture.

2. Surface quality and defect elimination
Multi-pass drawing effectively disperses the stress concentration caused by a single deformation through a step-by-step diameter reduction design. After each drawing, the surface of the titanium wire is polished and ultrasonically cleaned to gradually eliminate defects such as microcracks and inclusions. This process control allows the surface roughness of straight wires (0.8-4.0mm) for orthopedics and dentistry to reach Ra0.2μm or less, meeting the safety requirements of biocompatibility and long-term implantation.

3. Performance gradient regulation
For different application scenarios, the drawing process can achieve gradient regulation of titanium wire performance by adjusting the deformation amount, lubrication conditions and heat treatment parameters. For example, industrial titanium welding wires need to have good plasticity while maintaining high strength, while medical titanium wires require higher fatigue life and biocompatibility. This precise control capability is the core value of the multi-pass drawing process.

In the medical field, the multi-pass drawing process of titanium wire is directly related to the safety and effectiveness of implants. From cardiovascular anastomosis to orthopedic fixation systems, the performance of titanium wire determines the success rate of surgery and the quality of patient recovery.

1. Cardiovascular anastomotic titanium wire: life-saving suture with micron-level precision
0.20-0.28mm anastomotic titanium wire is a key consumable in cardiovascular surgery. Its multi-pass drawing process must ensure that the wire diameter tolerance is controlled within ±0.01mm and the surface finish reaches mirror level. This precision control allows the titanium wire to provide sufficient mechanical support when suturing blood vessels while avoiding damage to the blood vessel wall. For example, in coronary artery bypass surgery, the flexibility and corrosion resistance of titanium wire sutures significantly reduce the risk of postoperative restenosis.

2. Orthopedic and dental straight wire: a dual balance of biomechanics and aesthetics
0.8-4.0mm orthopedic and dental straight wires must meet both biomechanical stability and aesthetic requirements. The multi-pass drawing process optimizes the grain structure and surface morphology to enable the titanium wire to have a good elastic modulus match while maintaining high strength. In the field of dental orthodontics, the drawing process of titanium-nickel alloy wire can accurately control its superelasticity and shape memory effect, and realize the precise control of tooth movement; while in orthopedic implants, the fatigue life of titanium wire directly determines the long-term stability of the internal fixation system.

3. Microscopic guarantee of biocompatibility
The regulation of the oxide layer on the surface of titanium wire by multi-pass drawing process is the key to its biocompatibility. By controlling the lubrication conditions and subsequent heat treatment during the drawing process, a dense and stable TiO₂ oxide film can be formed on the surface of titanium wire. This nano-scale oxide layer can not only effectively block the release of metal ions, but also promote the adhesion and proliferation of osteoblasts, and significantly reduce the inflammatory response around the implant.

In the industrial field, the multi-pass drawing process of titanium wire provides key material support for high-end manufacturing such as aerospace and new energy. From the welding of engine blades to the sealing of deep-sea equipment, the performance of titanium wire directly determines the reliability and life of the equipment.

1. Titanium wire for aerospace welding: the art of connection in extreme environments
Industrial titanium welding wire needs to withstand the combined effects of high temperature, high pressure and strong corrosion. The multi-pass drawing process optimizes the alloy composition and microstructure, so that the welding wire can ensure the density of the weld and avoid thermal cracks and pore defects during the welding process. For example, in the repair of aircraft engine blades, the purity and plastic deformation ability of titanium welding wire directly determine the fatigue resistance of the welded joint.

2. Precision conductive wire in the field of new energy
In the field of fuel cells and water electrolysis for hydrogen production, titanium wire is a key material for the flow field of bipolar plates. Its multi-pass drawing process needs to take into account conductivity, corrosion resistance and mechanical strength. By regulating the grain orientation and surface state during the drawing process, the corrosion rate of titanium wire in acidic electrolyte can be reduced to below 0.01mm/a, while maintaining a stable resistivity at 5×10⁻⁶Ω·cm.

3. Special titanium wire for deep sea and nuclear industry
In deep sea equipment and nuclear reactors, titanium wire needs to withstand high pressure, strong radiation and corrosive media for a long time. The multi-pass drawing process can significantly improve the resistance of titanium wire to stress corrosion cracking by introducing intermediate annealing and surface modification technology. For example, the sealing titanium wire of deep-sea detectors needs to pass the -10,000 psi pressure test, while nuclear-grade titanium wire needs to meet the radiation tolerance requirements of a 50-year design life.