X17CrNi16-2

1.4057, also known as X17CrNi16-2 or AISI 431, is a martensitic, hardenable stainless steel with a working temperature up to approx. 500°C.

Its composition usually contains about 15-17% chromium and 1.5-2.5% nickel, 0.12-0.22% carbon along with small amounts of manganese (Mn) and silicon (Si). This composition contributes to its hardness, corrosion resistance and toughness.

1.4112 belongs to the group of martensitic stainless steels, characterised by a martensitic microstructure formed by quenching and tempering processes. This structure gives the steel high hardness, strength and wear resistance.

One of the defining characteristics of 1.4057 steel is its high hardness. It can achieve hardness levels up to HRC 50-55 after heat treatment, making it suitable for applications requiring excellent wear resistance, such as shafts, fasteners and components subjected to high mechanical loads.

Although not as corrosion resistant as austenitic stainless steels, 1.4057 offers good corrosion resistance in mild environments. Its chromium content provides resistance to corrosion, but it can be susceptible to corrosion in aggressive environments such as those containing chlorides.

Steel 1.4057 exhibits good toughness and impact strength, even at high hardness levels. This property makes it suitable for applications where resistance to fracture and deformation under mechanical stress is important.

Martensitic stainless steels such as 1.4034 are generally magnetic under all conditions, which can be advantageous in applications where magnetic properties are desired, such as in magnetic bearings or certain industrial applications.

Due to its combination of hardness, corrosion resistance and toughness, steel 1.4057 is widely used in applications such as shafts, fasteners, valves, pump components and surgical instruments. It is also used in industries such as automotive, aerospace, manufacturing and healthcare. Preheating of the material before welding is recommended.