Do You Know the Difference Between 18-8, 304, and 316?
Contrary to many people’s mistaken belief, all stainless steel may not be the same. What you invest in different stainless steel fastener types and grades will decide how corrosion-resistant they can be. Also, the durability will be judged.
Whether you are going to buy nuts, bolts, screws, nails, pins, rivets, or anchoring systems, you should also consider in which environment are you going to use them.
As a professional, you must be aware of the difference between 18-8, 304, and 316-grade stainless steel. Fair Wind Fasteners can offer the best quality of 316 stainless steel bolts and other fasteners that can be used in adverse environmental conditions.
To understand the differences, you must know some basic stainless-steel information, which is the general name of the alloy steels family that contains a minimum of 10.5% chromium as part of their composition.
At and above this chromium level, a complex chrome-oxide surface layer will prevent further oxygen atoms to penetrate into the steel and protect the iron from rusting.
Let us discuss each of these varieties briefly here.
18-8 GRADE STAINLESS STEEL
An 18-8 grade fastener will have chromium of 18% and nickel of 8%. Hence this variety has got better corrosion resistance as compared to 400 series. Only by cold working it is possible to harden and it is not magnetic.
Pros:
- It has superior corrosion resistance
- It can be molded and bent without any effect on its strength and durability.
- Extremely budget-friendly
- Requires little to almost no maintenance
- Can yield impressive
Cons:
- It shows corrosion signs when exposed to chlorides like salt
- Not suitable for marine application
304-GRADE STAINLESS STEEL
This basic alloy steel cannot be heat-hardened. Also, it is non-magnetic. It does not rust easily but may get tarnished. It can also resist the effects of various chemicals and acids strongly.
Pros:
-
- Usually considered one of the strongest available mild carbon steels on the market
- It has a high level of corrosion resistance
- Compared to 316 stainless steel you can easily mold this steel
Cons:
- It can easily be corroded when exposed to saltwater.
316 STAINLESS STEEL
This variety of stainless steel can offer very high tensile strength. Also, it has got a very high level of corrosion resistance. Besides that, it is a non-magnetic material.
So, it is necessary to harden this variety of material through cold working. This variety of stainless steel has also 2-3% added molybdenum. So, the degree of corrosion resistance of this material will be higher than the stainless steel of the 18-8 series.
The basic difference between 304 stainless steel and 316 stainless steel is the molybdenum incorporation of 316 reaches up to 3%. So, this variety of stainless steel is used usually in the paper pulp industry, surgical industry, and also for the production of chemicals and dyes.
Pros:
- It has higher strength and durability
- Better corrosion resistance as compared to 304 stainless steel even if exposed to saltwater
Cons:
- However, the price of 316 is much more than 304 costs.
Now you can select the right variety of stainless steel based on your application.