Stainless steel is commonly found in many industries and environments; from workstations and appliances in industrial kitchens to medical devices and automotive applications.
But like all metal alloys, stainless steel comes in many types and grades. Stainless steel can be graded based on its chemical composition, above the alloy series, such as 300, 400, etc. These general categories are known as austenitic, martensitic, and ferritic. In this article, we will explore austenitic stainless steel in more detail.
What is the difference between austenitic and martensitic stainless steel?
Austenitic stainless steel
Due to the presence of alloying elements, austenitic stainless steels have a face-centered cubic atomic structure, which means they are very tough and ductile enough to be bent and formed. Austenitic stainless steels have high levels of chromium and nickel.
Martensitic stainless steel
Martensitic stainless steels have a body-centered cubic atomic structure, are harder, and less ductile. This makes them ideal for making utensils such as knives and scrapers that require a sharp edge.
Why use austenitic stainless steel?
Machinability
Due to their crystal structure, austenitic stainless steels are relatively malleable and ductile. This means it is well suited to production manufacturing techniques such as bending, shearing, stamping and punching.
Cost
While stainless steel is slightly more expensive than mild steel, its ease of processing, combined with the lack of need for corrosion protection, means it is cheaper than some alternatives.
Strength
The tensile strength of grade 316 stainless steel is around 550 MPa, which is roughly equivalent to grade S355 mild steel (a medium-strength steel used in structural applications).
This means stainless steel can be used in place of steel for structural and other high-stress components, but with better corrosion resistance.