Food Grade Stainless Steel

What is Stainless Steel

Stainless steel refers to specific iron-based alloys with a minimum of 11% chromium. The alloy includes other metals, specifically nickel, and other elements like carbon. It’s the specific, and varied, elemental makeup that gives stainless steel the properties that make it valuable in multiple industries, particularly those where the metal will be exposed to harsh or difficult environmental situations.
Specifically, in the food industry, stainless steel is exposed to heat, water, and harsh cleaning chemicals. Through those exposures, food grade stainless steel must remain durable, rust/corrosion free, and be easy to sanitize. Further, the pitting resistance means it maintains a surface that’s easy to clean and maintain. Finally, the heat resistance of the metal means it can be exposed to extreme temperatures without risking damage.

Food Grade Stainless Steel 316

Grade 316 stainless is an austenitic stainless steel alloy with a high chromium and nickel content. Like many steel alloys, it has a continuous use temperature several times higher than most food making processes will ever require (more than 800°C, or 1472°F).

What makes the grade 316 alloy an ideal food grade steel sheet material is the fact that it has a high resistance to acids, alkalis, and chlorides (such as salt). Other austenitic stainless steels, such as grade 304 SS, can experience severe pitting corrosion when exposed to salt, which is often present in food products.

316 makes for great food grade stainless steel containers for nearly any food application.

Grade 430 Stainless Steel and Food

As an alloy, stainless steel 430 food grade metal is very similar to grade 316 stainless. It has the same chromium content as 316, but only a fraction of the nickel content, which makes it a more affordable alternative for some food makers.

Another major difference between 430 and 316 stainless steel is that grade 430 SS is a ferritic alloy, meaning that it’s magnetic by default. Ferritic alloys like 430 SS also have extraordinary resistance to stress corrosion cracking (the growth of crack formations that can cause sudden failure in corrosive environments).

430 SS has a strong resistance to nitric & organic acids and is often used for applications where prolonged contact with mildly acidic compounds is a concern. The alloy also boasts a resistance to sulfur and oxidation.

However, because of the low nickel content, this alloy is not as resistant to some dilute reducing acids as grade 316 stainless steel would be.