Chromoly Steel
Chromoly steel, short for chromium molybdenum steel, is a family of low alloy steels that contain small amounts of chromium and molybdenum in addition to iron and carbon. Common grades include 4130 and 4140. Adding chromium and molybdenum improves strength, toughness, hardenability, and fatigue resistance compared with basic carbon steel, which is why chromoly is often chosen when parts need to be strong without adding a lot of weight.
Chromoly steel is widely used for aircraft and race car tubing, roll cages, bicycle frames, drive shafts, axles, and other high stress components. It can be machined and welded, but the best welding results depend on the exact grade, thickness, and heat treatment condition, and some applications call for controlled preheat or post weld heat treatment. Chromoly is not stainless, so it can rust if left unprotected in wet or corrosive environments.
Chromoly steel is widely used for aircraft and race car tubing, roll cages, bicycle frames, drive shafts, axles, and other high stress components. It can be machined and welded, but the best welding results depend on the exact grade, thickness, and heat treatment condition, and some applications call for controlled preheat or post weld heat treatment. Chromoly is not stainless, so it can rust if left unprotected in wet or corrosive environments.
