Stainless steel refers to a group of iron-based alloys that contain a minimum of 10.5% chromium by mass. The chromium forms an ultra-thin layer, known as the “passive layer,” on the steel that enables it to resist corrosion. If this layer gets mechanically or chemically damaged, the passive layer self-heals itself. The addition of other elements like molybdenum, nickel, and nitrogen enhances the properties of stainless steel.
Stainless steel has been delivering phenomenal success in various industries for more than 70 years. It now comes in more than 60 grades. All of these grades come under four significant classes. It includes 300 Series Austenitic, 400 Series Ferritic, 400 Series Martensitic, and Precipitation Hardening. Due to their valuable properties, stainless steel pipe have increased service life and reduced cycle cost. It requires low maintenance and does not need painting or other protective coatings. The attractive appearance of stainless steel and its various properties, such as corrosion resistance, low maintenance, and high strength, make it more economically viable once you consider its service life and life-cycle costs.
Here are a few essential properties of stainless steel.
Corrosion Resistance
The chromium content of stainless steel imparts to it valuable corrosion resistance properties. The chromium helps form a self-healing layer on the steel surface, making it resistant to corrosion. Hence even if the steel surface gets cut or damaged, it gets self-healed. 304 stainless steel shows excellent corrosion resistance and value and can withstand corrosion from most oxidizing acids.
Cryogenic Resistance
You can measure cryogenic resistance by the material’s toughness or ductility at sub-zero temperatures. The tensile strengths and toughness of austenitic stainless steel at cryogenic temperatures are substantially higher than ambient temperatures. However, at sub-zero temperatures, you should not use martensitic, ferritic, or precipitation hardening steel. As the temperature drops, its toughness tends to decrease.
Work Hardening
The work-hardenable grades of stainless steel allow you to achieve higher strength using cold working. Combining annealing and cold working stages will help you impart the required strength to the stainless steel.
Hot Strength
At high temperatures, the austenitic grade can retain its high strength. Such properties are conducive to stainless steel with high chromium levels of silicon, nitrogen, and rare earth elements. Ferritic grade with high chromium also shows high hot strength. It enables it to display resistance to scaling at elevated temperatures.
Biologically Inert
Stainless steel is biologically inert. Hence, it is highly suitable for medical equipment like surgical tools, plates, and trauma screws. The inertness also makes it ideal for kitchen appliances and cutlery products.
Recyclability
You can recycle stainless steel to make new products. It helps to reduce strain on the environment and decreases the need for raw materials. It also helps to minimize waste formation. Since it is non-biodegradable, it does not contaminate resources, as it cannot break down and seep into water reservoirs or soil.
Ductility
The ductility of stainless steel varies across its various grades. Some grades have high ductility, which renders them suitable for strenuous deep-drawing methods.
To Conclude:
These are a few important properties of stainless steel. It makes stainless steel highly valuable across various industries to deliver success.