What Is L80 Alloy Steel?

L80 alloy steel is a controlled-yield, low-alloy chromium-molybdenum (Cr-Mo) engineering steel characterised by a yield strength range of 552–655 MPa (80–95 ksi) and a maximum hardness of 23 HRC. The ‘80’ in L80 designates the 80 ksi (552 MPa) minimum yield strength, while the controlled maximum yield and hardness ceiling distinguish L80 from standard high-strength Cr-Mo grades such as 4140 or EN19, which have no upper yield or hardness limits.

L80 alloy steel is produced using chromium (up to 1.50%) and molybdenum (up to 0.25%) as primary alloying elements, giving it good hardenability, high strength in normalised and quench-and-tempered condition, and resistance to mechanical degradation under demanding service conditions. The combination of minimum and maximum yield strength limits makes L80 a ‘controlled-yield’ grade — ensuring the material is neither too weak nor over-hardened, which is critical for components requiring predictable deformation behaviour and resistance to brittle failure.

At Nifty Alloys, we supply L80 alloy steel in round bars, seamless pipes, hollow bars, flat bars, and plates from our Dubai warehouse, with EN 10204 3.1 mill test certificates for full chemical and mechanical traceability, available for immediate dispatch to UAE, GCC, and global engineering and oil and gas project destinations.