Stainless Steel Processes and Properties Explained
The basic properties of any stainless steel grade are pretty desirable on their own. These are the properties that make stainless steel better than other material in numerous aspects. What is best about these properties is that they can be enhanced by putting stainless steel through a number of different processes. Once these processes, also known as fabrication of stainless steel, are carried out, the desirable features and properties of the stainless steel become even more impressive. This is mainly done to make stainless steel more suitable for certain applications that have very specific requirements.
Here we will be looking at 4 of the main processes that alter the properties of stainless steel.
1) Work Hardening of Stainless Steel
Work hardening is the process by which materials such as stainless steel are strengthened. This increase in the strength of the material, in this case stainless steel, is achieved through deformation. Stainless steel can be work hardened in a relatively short period of time. The rate of the hardening can differ amongst the specific grades of stainless steel. For instance, austenitic stainless steel has the ability to work harden faster than carbon steel.
There are many different kinds of work hardening treatments that are applied to stainless steel. If you want to strengthen stainless steel in the most efficient manner possible, then choose the work hardening treatment that best suits the properties and features of the stainless steel grade you are dealing with.
Besides adding to the strength of stainless steel, work hardening treatments can enhance the magnetism of stainless steel.
2) Addition of Manganese Sulfide
Specific grades of stainless steel such as 303, 430, 410 and 416 can become more resistant to chipping when they are alloyed with a particular compound called manganese sulphide. In other words, the resistance of the stainless steel is increased and the ductility of the material is significantly decreased. It is worth noting that adding manganese sulphide to stainless steel makes it more difficult for the material to be machined.
3) Tempering of Stainless Steel
The tempering of stainless steel is a follow up to work hardening. It is a heat treatment process which is carried out in a relatively low temperature (below A1). The main purpose of putting the stainless steel through this process is to further increase the hardness/toughness ration.
Tempering is generally carried out inside specialized furnaces that have a protective gas feature that reduces the chances of oxidation taking place on the surface of the steel.
4) Stress Relieving
Stress relieving, as the name suggests is performed on stainless steel (and other metals) to ensure that residual stresses on the structure are lowered to a minimum. This nearly eliminates the possibility of unwanted changes in dimension when the component is being used by the consumer.
Welded structures often need to be made tension free. This is when stress relieving comes into play. Rough machining generally precedes stress relieving. Polishing and grinding comes afterwards.
Stainless Steel Cleaning
Stainless steel can be cleaned during or after fabrication. Before stainless steel can be cleaned, one has to determine the substance that has to be removed. These range from shop oils (dirt, grease, grit and metal chips), to conversion oils (short time anneal oxides) to lubricant oxide mixtures (hot work scales).
When it comes to stainless steel cleaning after fabrication (welding), the same principle applies. The main factors that influence the choice of cleaning method are certainly the thickness of the material and the type of weld.
Cougartron offers a wide range of machines and solutions for various types of welds – from light TIG to dark MIG welds.
If you would like to know more about stainless steel weld cleaning and Cougartron machines, click below to read our detailed article.