Welding 4340. Ive been told this is a heat-treatable steel. AISISAE 4340 Alloy Steel 4340 is a nickel-chromium-molybdenum alloy steel known for its toughness and its ability to attain high strengths in the heat-treated condition.
For the best mechanical properties the material should be welded in the annealed condition. Eureka Welding Alloys 2000 E. Preheat and post heat weld procedures are followed while welding this steel by established methods.
4140 can be easily welded with the right precautionary steps being applied.
Otai steel is one leading supplier of 4340 steel equivalents. For the best mechanical properties the material should be welded in the annealed condition. These consumables matching strength but have high risk of hydrogen cracking thus proper preheating fully baked low hydrogen electrodes and slow cooling is mandatory. AISI 4340 steel can also be produced as light plates and castings.