AISI 5160 is a Standard grade Alloy Steel. It is commonly called AISI 5160 Chromium steel. It is composed of (in weight percentage) 0.56-0.64% Carbon (C), 0.75-1.00% Manganese (Mn), 0.035%(max) Phosphorus (P), 0.04%(max) Sulfur (S), 0.15-0.30% Silicon (Si), 0.70-0.90% Chromium (Cr), and the base metal Iron (Fe). Other designations of AISI 5160 alloy steel include UNS G51600 and AISI 5160.