Alloy 904L is a low carbon high alloy austenitic stainless steel. Copper gives this grade improved resistance to strong reducing acids such as sulfuric acid. This alloy is very resistant to pitting, crevice corrosion, and stress corrosion cracking caused by chlorides. Alloy 904L is a high chromium-nickelmolybdenum- copper alloy exhibiting excellent corrosion resistance, has good formability and weldability, and resists intergranular corrosion. This alloy is used in acid production, pulp and paper processes, gas scrubbers, oil refining, and seawater cooling.