Stainless Steel Grade AISI 303Se

AISI 303Se | S30323 is a non-magnetic, austenitic stainless steel that is not heat treatable. It is free machinable, specifically designed to exhibit improved machinability. Selenium (Se) replaces sulfur, providing free machinable characteristics and has slightly improved formability compared to AISI 303.

The good mechanical and corrosion-resistant properties of the low-sulphur grade are retained as much as possible. AISI 303Se is an excellent choice for machining, but the metal is not very easy to weld.

Density of steel = 8.0 g/cm³. Non-magnetic.

Mechanical properties

Table: mechanical properties of stainless steel grade AISI 303Se | S30323
Tensile strength, min., MPa	620
Yield strength, 0.2%, MPa	240
Relative elongation, min., %	30
Hardness, HB type	213
Modulus of elasticity kN/mm²	193

Mechanical processing

AISI 303Se grade can be machined at low speeds and feeds. Selenium makes this material very brittle.

Welding

Welding at high temperatures is not recommended because the selenium in this material tends to precipitate at the weld edge, causing weak and brittle joints. However, welding can be done at low temperatures with the recommended filler.

Heat treatment

Annealing of the grade can be done at 1010 °C - 1066 °C followed by rapid cooling. Cold working can be used to increase the hardness and strength of this material. Hot working, such as forging and upsetting, can be done when the material is well heated to 1149 °C - 1260 °C. Hot working at temperatures below 927 °C is not recommended. Rapid cooling after work improves anti-corrosion properties.

Table: chemical composition of steel grade AISI 303Se | S30323
Chemical composition of steel grade AISI 303Se \| S30323
C	Si	Mn	P	S	Cr	Ni	Se	Mo	Cu	Fe
0,15	<1,0	<2,0	<0,20	<0,06	17,0-19,0	8,0-10,0	0,15-0,40	<1,0	<1,0	Other

Application

Stainless steel of this grade is widely used in screw and general mechanical engineering. Various equipment, fasteners, valve parts, nozzles, etc. are made from this alloy metal.