Alloy 20 (Carpenter 20) is an austenitic nickel-iron-chromium alloy developed for maximum corrosion resistance in highly acidic environments. It contains a combination of Nickel-Iron and Chromium and a small amount of Molybdenum, Copper and Titanium to deliver superior anti-corrosive properties while providing exceptional strength even under extreme temperature fluctuations. The balanced chemistry makes it extremely resistant to stress cracking and intergranular corrosion, issues commonly seen with other alloys.
Alloy 20 is a stainless steel nickel alloy well suited for chemical, food processing, pharmaceutical and petrochemical applications. It has excellent resistance to corrosion by sulfuric acid and other strong reducing acids and good stress-corrosion cracking resistance in chloride-bearing solutions. Combining molybdenum and copper with nickel makes Alloy 20 resistant to crevice corrosion attack. Cold working also improves its strength and hardness, making it suitable for use at extreme temperatures. Additionally, its flexibility makes fabricating into parts such as valve stems or fasteners easier than many other grades of stainless steel alloys.