1.4057 stainless steel maintains its high toughness and tensile properties in the quenched and tempered condition. This makes it ideal for bolt and shaft applications. As with other common stainless steel grades, it is resistant to chemical attack from a range of biological media, organic matter, and various corrosive elements. This makes 1.4057 stainless steel uniquely suited for medical and food contact devices, as well as for complex machinery in shipbuilding applications.

One of the most rounded stainless steel grades on the market, 1.4057 stainless steel is an outstanding engineering material for demanding applications. It is a martensitic chromium alloy with exceptional corrosion resistance and versatile thermodynamic properties. Inherently resistant to salt water and scaling at continuous operating temperatures of 870°C, 1.4057 stainless steel is a widely-used engineering alloy for marine applications.

Benefits of Using 1.4057 Stainless Steel

Good resistance to seawater and water of varying salt concentrations
Easily machined into complex parts
Suitable for hygiene-critical applications

Mechanical properties of 1.4057 stainless steel

Description	1.4057 Stainless Steel
Tensile Strength (MPa)	<1000
Yield Strength (MPa)	1080
Elongation (% in 50mm)	20
Hardness (HB)	<388
Impact Charpy V (J)	50 – 84

1.4057 stainless steel boasts an exceptional blend of wear- and corrosion-resistance, impact toughness, and high strength. The exact ultimate tensile strength (UTS) values of the material vary, but you can typically expect billets of 1.4057 stainless steel to display a UTS upwards of 800MPa. This property can be finely-tuned through specific heat treatment to acquire a unique balance of mechanical to chemical characteristics. 1.4057 stainless steel is broadly resistant to oxidizing acids and corrosion from salt water, suiting it for complex engineering projects in marine applications.

Chemical composition of 1.4057 stainless steel

UNS No	S43100
AISI	431
Carbon (C)	0.12 – 0.22%
Chromium (Cr)	5—17%
Manganese (Mn)	<1.0%
Nickel (Ni)	0.025
Phosphorous (P)	<0.04%
Silicon (Si)	<1.0%

ASTM 431, or 1.4057 stainless steel, is the comprehensive martensite grade for engineering applications. The exact composition varies, but an exemplary 1.4057 stainless steel will comprise: 15 – 17% chromium; 2 – 2.5% Nickel; 0.12 – 0.22% Carbon. It may also comprise small volumes of molybdenum, silicon, and phosphorous.

Chromium is the primary alloying element of martensitic steels such as 1.4057 stainless steel, imparting moderate corrosion resistance to a material with inherently high hardness and strength. In the unquenched and un-tempered condition, martensitic grades are brittle and unsuitable for engineering applications. Typically, nickel concentrations of 2 – 2.5% are added as a stabilizing element to ensure a martensitic steel retains its toughness properties through heat treatment, enabling the fabrication of numerous component types. Medical tools and mechanical components are among the most common devices constructed from martensitic steels.