Why choose a high-quality GR2 titanium sheet for use in chemical equipment in alkaline environments?

In chemical production, the choice of material directly affects the operational stability and service life of the equipment. Titanium is the ideal material for use in highly corrosive environments thanks to its unique performance advantages. When titanium is exposed to oxygen, a dense, self-repairing layer of passivated oxide (TiO₂) spontaneously forms on the surface. This protective film is only 3–5 nanometres thick and has remarkable stability, effectively isolating corrosive media. Studies have shown that the breakdown potential of this oxide film is as high as 12 V, which is much higher than the 0.5 V of stainless steel. This gives titanium excellent resistance to oxidising acids and chlorides. Titanium also maintains excellent corrosion resistance over a wide pH range (2–12), which is unmatched by most engineering metals.

Commercially pure GR2 titanium(CP Grade 2) is the go-to material in the industrial sector thanks to its perfect balance of mechanical properties and corrosion resistance. It typically consists of over 99.2% pure titanium, with strict control of trace elements such as iron (≤0.3%) and oxygen (≤0.25%). This precise control of composition gives the material a tensile strength of 240–345 MPa and a yield strength of 170–275 MPa while maintaining an elongation of over 20%. Notably, the crevice corrosion resistance of GR2 titanium is approximately 30°C higher than that of GR1, with a critical crevice corrosion temperature of up to 80°C. In practice, GR2 titanium's welding performance is outstanding, with a weld strength coefficient of 0.9 or more — far better than high-strength Titanium Alloys at 0.7–0.8. This material has medium strength and good ductility, and its self-repairing passivation film is more effective at preventing local erosion. Experimental data show that the annual corrosion rate of GR2 titanium in a 3.5% NaCl solution is less than 0.0025 mm, which is almost negligible.

In alkaline environments, GR2 titanium performs well in lye at ambient to medium temperatures, although high temperature and high lye concentrations may pose a challenge to passivation film stability. At temperatures below 80°C and NaOH concentrations below 40%, the annual corrosion rate of GR2 Titanium can be controlled to within 0.01mm. With specialized surface treatment such as nitric acid passivation (20-30% HNO3 solution for 20-30 minutes), the oxide film thickness can be increased to 10-15 nm, significantly improving the corrosion resistance. Optimized manufacturing processes, such as the use of 99.999% high-purity argon gas protection welding, can make the weld zone corrosion resistance is comparable to the base material. In terms of welding parameter control, it is recommended to use a smaller heat input (1.0-1.5kJ/mm), and the interlayer temperature is controlled below 150°C, which can effectively avoid welding contamination. These process measures can further enhance its alkali resistance and ensure the long-term stable operation of the equipment in harsh environments.

Thanks to this property of titanium, this high-quality material is widely used in many industrial fields. For instance, in the chlor-alkali industry, it is used to manufacture electrolysis tanks and piping systems. In desalination plants, it is used as an evaporator material. In the paper industry, it is used in cooking equipment. In chemical production, it is used to manufacture key equipment, such as reactors and storage tanks. These applications demonstrate the excellent performance of GR2 Titanium Sheet in harsh environments.

Baoji ProX Metal Materials is a professional titanium supplier that has been committed to providing customers with high-quality, cost-effective titanium and titanium alloy material solutions for over 20 years. The company offers a comprehensive range of titanium products, including sheets, bars, pipes and wires. GR2 titanium sheet is the ideal material for environments with strong alkali corrosion due to its excellent performance. Please contact us at info@titaniumprox.com or on WhatsApp on +86-13892756186 for more product information or professional advice.