Strengthening Stainless Steel Products by Annealing
Stainless steel is known for being a strong and resilient material, but sometimes, we need it to be even stronger. There are multiple ways to strengthen stainless steel, one of them being heating the metal. In this article, we’re going to look at a specific type of heat treatment: annealing. This process relieves internal stresses in the metal to strengthen stainless steel products. Annealing improves the ductility of the metal and softens the steel so it can be more easily processed or formed.
Let’s take a look at the process, effects, and applications of annealing to strengthen stainless steel products.
Process
The process of annealing includes three basic steps:
- Heating: naturally, the process starts by heating the metal. This requires very high heat, usually in the range of 1900-2100°F, depending on the grade of stainless steel and the desired outcome.
- Soaking: This is different from quenching, which does not happen in this type of heat treatment. In this context, “soaking” means holding the metal at temperature. Once at temperature, the steel needs to remain at that temperature for a sufficient amount of time to allow the internal structure to reach equilibrium.
- Cooling: To preserve the new internal structure, the metal needs to cool slowly, either in the furnace itself or by controlled air cooling. The rate of cooling is critical to prevent the formation of new stresses or cracks.
Effects
Annealing stainless steel changes the structure and characteristics of stainless steel. Here are three primary effects of annealing:
- Softening: Annealing reduces hardness and increases ductility by allowing the steel to recrystallize and form a more uniform structure.
- Stress Relief: It eliminates internal stresses that may have accumulated during previous manufacturing processes like rolling or machining.
- Machinability: Annealed stainless steel is easier to machine and form, making it suitable for subsequent manufacturing operations.
Applications
Annealing isn’t the last thing done to stainless steel products. The point of the process is to make further shaping or machining easier. Annealing is commonly used before further processing, such as cold working, machining, or welding. It can also restore ductility to stainless steel that has become work-hardened during manufacturing.
Stainless Steel Products from Alliant Metals
At Alliant Metals, we provide high-quality stainless steel products for several industries and applications. Contact us at 800-329-4488 to speak with our team to find the right products and services for your project and industry.
