41xx steel

41xx steel is a family of SAE steel grades, as specified by the Society of Automotive Engineers (SAE). Alloying elements include chromium and molybdenum, and as a result these materials are often informally referred to as chromoly steel (common variant stylings include chrome-moly, cro-moly, CrMo, CRMO, CR-MOLY, and similar). They have an excellent strength to weight ratio and are considerably stronger and harder than standard 1020 steel, but are not easily welded, requiring thermal treatment both before and after welding to avoid cold cracking.

41xx steel

41xx steel is a family of SAE steel grades, as specified by the Society of Automotive Engineers (SAE). Alloying elements include chromium and molybdenum, and as a result these materials are often informally referred to as chromoly steel (common variant stylings include chrome-moly, cro-moly, CrMo, CRMO, CR-MOLY, and similar). They have an excellent strength to weight ratio and are considerably stronger and harder than standard 1020 steel, but are not easily welded, requiring thermal treatment both before and after welding to avoid cold cracking.