Washington alloy 4130 low alloy
Washington Alloy 4130 is a low alloy, copper-coated steel wire designed for TIG, MIG and submerged arc welding of heat-treatable, low alloy steels such as the SAE 4100 series and 8630 as well as steel castings with similar hardening characteristics. A pre-heat temperature of 300-350 is required for some of the higher carbon grades in order to prevent cracking. Many other grades can be welded without a preheat.
98% Argon (Ar) and 2% Oxygen (O2) or pure Argon (Ar)
Proper heat treatment will produce a tensile strength of 150,000 to 160,000 psi.