Grade 316 stainless steel is a highly corrosion resistant type of standard grade stainless steel. Have you ever wondered why this alloy fits in such a wide range of applications including heat exchangers, boat fittings, and threaded fasteners among many others? Stainless steel is generally suitable for many processing and related industries, but 316 stainless steel is unique. While every steel contains the same percentage of carbon and iron, 316 stainless steel offers a higher level of corrosion resistance among other superior characteristics. In the next section, you will learn about various 316 stainless steel properties that make the material ideal for harsh chemical and saline environments.
Composition of 316 Stainless Steel
Grade 316 stainless steel belongs to a stainless steel family that also comprises of 304, 302, 347 and others. It falls under the umbrella of Austenitic steel category, which includes specialty alloys, manganese-chromium-nickel-nitrogen alloys, and common chromium-nickel alloys. This type of steel is common in many food processing, power, and chemical plants. It is easily distinguishable from the rest because of its excellent corrosion resistance. In welding applications, this alloy comes in handy because of low carbon content-minimal carbide precipitation.
The nominal composition of this stainless steel in percentages is as follows:
316 Stainless Steel Properties
Grade 316 stainless steel comes with a minimum tensile stress of 515 MPa, a minimum yield stress of 205 MPa, and a minimum elongation of 40% in 50mm.
At room temperature, Grade 316 stainless steel also exhibits the following set of properties:
- Density 99 g/cm3
- Thermal Expansion 9 mm/m/°C
- Electrical Resistivity 4 μohm/cm
- Thermal conductivity 3 W.m -1.°K-1
- Modulus of elasticity 193 GPa
Below is a discussion of several 316 stainless steel characteristics:
Corrosion occurs when the outer surface of a component deteriorates because of chemical attacks. Once this happens, contaminants can enter the inner layers of the component. Corrosion resistance is probably the biggest asset of this alloy. You will often hear it referred to as “marine grade” owing to this characteristic. 316 stainless contains at least 2 percent of molybdenum, which gives it more corrosion resistance as compared to other steels.
Like other austenitic stainless steels, 316 stainless steel features excellent fabrication characteristics. The material deep draws very easily, making it suitable for the manufacture of sinks and similar stainless steel parts.
This stainless steel has excellent oxidation resistance both in continuous service and in intermittent service. The maximum temperatures in both cases are 925°C and 870°C respectively.
Who Needs 316 Stainless Steel?
If you are a manager or proprietor dealing with industrial components, coastal/marine applications or any other thing exposed to corrosive chemicals, you might want to use 316 stainless steel equipment/components. The alloy provides superior performance in a wide range of areas. Its resistance to chloride finds application in areas with salt deposits, especially in colder climates. Also helpful is the ability of the steel to withstand corrosive chemicals, such as sulphuric and acetic acids. Remember that these types of chemicals are rampant in the manufacture of rubber, paper, and textiles and so on. Based on these characteristics, this steel alloy has been central to applications in the following industries:
- Architectural buildings in colder climates
- Structures in coastal areas
- Evaporators and condensers
- Laboratory equipment
- Food processing equipment
- Paper machinery
- Pharmaceutical industries
Care and Maintenance of 316 Stainless Steel
Sustaining 316 stainless steel properties is about proper cleaning and maintenance of the equipment. Method and frequency of cleaning depends on many factors, among them, the type of process and nature of product. Here are some cleaning methods applied for 316 stainless steel equipment in food processing industries:
- Mechanical scrubbing
- Use of organic solvents
- Use of alkaline solutions
- Water and steam
- Use of nitric acid
Many 316 stainless steel machines have components that may absorb fluids. With evaporation, these fluids may become concentrated and cause corrosion on the component. Occasional dismantling and cleaning of equipment should take control of this issue.
There are numerous stainless steel varieties in the market. This may cause confusion to a buyer who is not familiar with the best stainless steel for chemical, consumer or structural application. The problem is that often, many people consider stainless steel as a singular item. This is erroneous and may lead to disappointment. Therefore it’s important to know a bit about the properties of each type of stainless steel alloy. We hope that this article has given you a solid insight specifically into 316 stainless steel properties. As you determine which steel alloy you need, do not look any further if your application is something to do with food processing, laboratory equipment, or coastal buildings.