Although the titanium bar itself has excellent corrosion resistance, but in some specific environments, we still need to carry out its surface treatment to enhance its corrosion and wear resistance. Below, I will give you a detailed introduction to the process of surface treatment of titanium rods:
Atmospheric oxidation treatment:
Process description: the titanium rod is placed in a high temperature atmosphere to thicken the oxide film on its surface. The thickness of the oxide film increases with temperature and time.
Effect: This method is effective for both total and interstitial corrosion of titanium, and the method is relatively simple.
Limitations: Durability is not sufficiently reliable because the thickened oxide film will thin over time in a corrosive environment, eventually leading to corrosion.
Wet Coating Method:
Process description: Cr, Ni-P are mainly plated on titanium rods. due to the difficulty of plating Cr directly on titanium rods, Ni is usually plated first, then Cr.
Effect: Electrolytic method of film formation is fast, the thickness can reach several microns, is an effective wear-resistant surface treatment method.
Thermal diffusion method:
Process description: The use of glow discharge plasma to destroy the oxide film on the surface of titanium, followed by nitriding.
Effect: The thickness of nitrided film can be increased from 0.7um to 5.0um, and the surface hardness reaches 1200-1600Hv, which has good wear resistance.
Surfacing method:
Process description: the use of plasma transfer arc for titanium plate surface surfacing hardening modification.
Effect: excellent wear resistance, simple method, can prevent the decline of mechanical properties.
Limitations: limited to handling only thicker large workpieces.
Sputtering method:
Process description: Utilizing plasma flow high-speed air jets, the drops of molten metal are sprayed on the surface of titanium rods.
Effect: High production efficiency, but the coating is not dense enough.
Precious metal coating:
Process description: Coating precious metals (e.g. Pd, Ru) or their oxides (e.g. PdO, RuO2) on the surface of titanium.
Effect: Significantly improve the corrosion resistance of titanium, the corrosion resistance of the coating treated material can match that of Ti/0.15Pd alloy.
Limitations: The precious metal film may peel off from the titanium surface during prolonged use in fluids or fluids containing solids.
In summary, there are various surface treatment processes for titanium rods, each with its unique advantages and limitations. In practical applications, we need to choose the appropriate surface treatment process according to the specific use of the environment and requirements, in order to enhance the corrosion and wear resistance of titanium rods, and improve their overall performance.
