Stainless Steel - Grade 308 (UNS S30800)

Stainless Steel is one of the most prominent materials used in various industries. Its increasing popularity and reliable usage across various industries have resulted in a sudden increase in its demand. Owing to different requirements of different industries various variations were done in terms of stainless steel chemical composition, resulting in different grades of stainless steel. 

In this article below, we will be reading about one such unique stainless steel; Grade 308.

About Grade 308 Stainless Steel

Stainless Steel Grade 308 or UNS S30800 is austenitic steel composed of a good amount of chromium, nickel and manganese along with other metals. The rich constitute of Grade 308 provides it with high corrosion resistance, good weldability and formability. It also has high mechanical properties at varied temperatures. It is largely used in metalworking applications like kitchenware, medical equipment, etc. 

AISI 308 Chemical Composition

It is the chemical composition of stainless steel that provides it with its unique characteristics. With a good amount of chromium and nickel, SS Grade 308 is highly corrosion-resistant. Let us have a detailed look at the chemical composition of Grade 308 stainless steel before moving on to its other properties.

Iron, Fe

66%

Chromium, Cr

20%

Nickel, Ni

11%

Manganese, Mn

2.0%

Silicon, Si

1.0%

Carbon, C

0.080%

Phosphorous, P

0.045%

Sulfur, S

0.030%

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Physical Properties of Stainless Steel Grade 308

Density affects the properties of steel, such as strength, durability, malleability, ductility, electrical conductivity, heat capacity, thermal expansion rate, etc. Hence it becomes crucial to understand its physical properties including density, before finalizing it for your application. Here is the physical property of stainless steel grade 308 to help you make a wise decision.

Density

8 g/cm3

 

 

 

Mechanical Properties of Stainless Steel Grade 308

Like the physical properties, the mechanical properties of stainless steel also play a crucial role in establishing its suitability for various applications. Here is a sneak peek into the mechanical properties of stainless steel.

Tensile strength

585 MPa

Yield strength (@ strain 0.200%)

240 MPa

Izod impact

135 - 165 J

Charpy Impact

135 J

Elastic modulus 

193 GPa

Poisson's ratio

0.27-0.30

Elongation at break (in 50 mm)

50%

Hardness, Brinell

139

Hardness, Knoop (converted from Rockwell B hardness)

155

Hardness, Rockwell B (converted from Rockwell B hardness)

80

Hardness, Vickers (converted from Rockwell B hardness)

153

 

Thermal Properties of Stainless Steel Grade 308

The thermal properties of stainless steel determine its nature during extreme temperatures. Let us have a quick look at the thermal properties of Grade 308.

Thermal expansion coefficient (@ 0-100°C/32-212°F)

17.3 µm/m°C

Thermal conductivity (@ 0-100°C/32-212°F)

15.2 W/mK

 

Applications of Stainless Steel Grade 308

Grade 308 finds its extensive usage in applications where corrosion resistance is critical. Also being highly weldable, it is commonly used for welding to ensure a strong, durable weld. 

  • Kitchen appliances,
  • structural supports, 
  • Chemical processing equipment,
  • Food processing, 
  • Medical equipment manufacturing industry