Processing and Fabricating Alloy 825 for Optimized Properties and Corrosion Resistance

Alloy 825 (UNS N08825) is an iron-nickel-chromium-molybdenum corrosion-resistant alloy stabilized by its content of titanium. While the alloy was developed over 50 years ago, it is still in widespread use for refinery and petrochemical applications. The properties and corrosion-resistance of alloy 825 are greatly dependent upon the thermal-mechanical processing of the material. The final anneal is critical in developing the corrosion resistance of the product. Process techniques and heat procedures are reviewed and their effects on properties evaluated. It is shown that the proper combination of processing and heat treatment result in optimum properties for the alloy for the defined service.