1.4301 Bar and Section

1.4301 Specification

1.4301/Type 304 is the most widely used stainless steel grade, as well as being the most versatile. Type 304 is an austenitic grade that can be deep drawn, making it the dominant grade used for common household applications such as sinks and saucepans. Sometimes referred to by its old name 18/8, it’s composition consists of 18% chromium and 8% nickel. 1.4307/Type 304L is a low carbon variant of the 304 grade, often used in heavy gauge components for improved weldability. 304 is also very corrosion resistant in most environments it is used, even when in contact with corrosive materials. Corrosion can occur though, with pitting/crevice corrosion happening in environments than contain chlorides as well as stress corrosion cracking, when above temperatures of 60°c


Applications

304 Stainless Steel is used in the following:

Sinks & splashbacks
Cutlery & metal tableware
Saucepans
Springs, screws, bolts and nuts
Tubing


Chemical Composition

Element % Present
Chromium (CR) 17.50 – 19.50
Nickel (Ni) 8.00 – 10.50
Manganese (Mn) 0.0 – 2.00
Silicon (Si) 0.0 – 1.00
Nitrogen (N) 0.0 – 0.11
Carbon (C) 0.0 – 0.07
Phosphorous (P) 0.0 – 0.05
Sulphur (S) 0.0 – 0.03
Iron (Fe) Balance

Alloy Designations

Stainless Steel Grade 1.4301/304 also corresponds to the following designations but may not be a direct equivalent:

S30400
304S15
304S16
304S31
EN58E


Mechanical Properties

Property Value
Proof Stress 190 Min MPa
Tensile Strength 500 to 700 MPa
Elongation A50 mm 45 Min %
Hardness Brinell 215 Max HB

Machinability

The 304 grade has good machinability which can be enhanced by using the following techniques:

• Keep cutting edges sharp as dull edges cause excess work hardening
• Cuts should be light but deep enough to prevent work hardening by riding on the surface of the material.
• Chip breakers should be employed to assist in ensuring swarf remains clear of the work
• Low thermal conductivity of austenitic alloys results in the heat concentrating at the cutting edges. This means coolants and lubricants are necessary and must be used in large quantities.