What is Stainless Steel? (with pictures)

What is Stainless Steel?

By Garry Crystal

Updated May 17, 2024

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Stainless steel is the universal name for a number of different steels used primarily for their anti-corrosive element. This steel has been developed to resist a number of corrosive environments. It ensures that our workplaces are safe, that buildings last longer and that our food preparation surfaces are hygienic. It is also an earth friendly material; it can be melted down, recycled and made into something else.

Stainless steel is always made using chromium. The minimum amount of chromium used is 10.5%; it is chromium that makes the steel stainless. Chromium also improves the corrosion resistance by forming a chromium oxide film on the steel. This very thin layer, when placed under the right conditions, can also be self-repairing.

There are other elements used to make this steel as well, including nickel, nitrogen and molybdenum. Bringing these elements together forms different crystal structures that enable a variety of properties in machining, welding and forming.

There are four major types of stainless steel. Of these, austenitic is the most widely used type. It has a nickel content of at least 7%, which makes it very flexible. It is used in a range of houseware products, industrial piping and vessels, constructional structures and architectural facades.

Ferritic stainless steel has similar properties to mild steel, but better corrosion resistance. This type of steel is commonly used in washing machines, boilers and indoor architecture. Martensitic stainless steel is a very hard, strong steel. It contains around 13% chromium and is used to make knives and turbine blades.

There is also a duplex steel that is a composite of austenitic and ferritic steels. This steel is both strong and flexible. Duplex steels are most commonly used in the paper, pulp and shipbuilding industries. They are also widely used in the petrochemical industry.

Stainless steel is a very versatile material. It can literally be used for years and remain stainless. Products made from it have a significantly longer lifespan than products made of other materials. The maintenance costs are lower, and stainless steel also has a very high scrap value.

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Discussion Comments

By honeybees — On Sep 08, 2012

@StarJo: I have stainless steel cookware but it is not considered nonstick. I use some olive oil or some other type of cooking spray to keep food from sticking.

It has been years since I got rid of all of my nonstick cookware. When I read some of the studies about the chemicals they leaked out into your food, I made the change to stainless steel.

Another advantage to using stainless steel cookware is this will last a lifetime if you take care of it. My mom has been using the same stainless steel set of pans for 50 years and you would never guess from looking at them they are that old.

By JackWhack — On Sep 07, 2012

I think that stainless steel appliances are beautiful. They just look so modern and expensive.

My neighbor has all stainless steel appliances in her kitchen. She has a huge silver refrigerator that looks so shiny and cool. I love the fact that it matches her dishwasher and stove.

If I could afford all new appliances, I would get stainless steel. I will probably just buy one at a time as they need replacing. That will be a good way to build up my stainless steel collection.

By OeKc05 — On Sep 07, 2012

@StarJo: No, they aren't nonstick pans. In fact, food seems to stick to them a lot.

I've noticed that when I cook meat in a stainless steel pan, even if I add cooking oil first, it sticks to the pan. This is frustrating when I'm trying to fry chicken, because it strips the batter right off of the meat.

If you want a nonstick pan, don't buy a stainless steel one. Stainless steel pans are great for caramelizing food like onions, but they are awful for cooking meat.

By myharley — On Sep 06, 2012

@julies-- Have you tried any of the special cleaners made specifically for stainless steel products? These cost more than a regular cleaner, but this is the only thing I have found to keep my stainless steel appliances clean and streak free.

The cleaner I use sprays out like a foam and I spray this on a towel instead of directly on the appliance. I use the moist towel to wipe it down and follow up with a dry towel for a clean, shiny look. It's too bad it doesn't last a little bit longer than it does, but at least it stays clean for awhile anyway.

By StarJo — On Sep 05, 2012

Do all stainless steel pans have nonstick surfaces? I've always just assumed that food would not stick to stainless steel. Maybe the word “stainless” makes me think that nothing will be left behind on the surface.

By julies — On Sep 05, 2012

I have stainless steel appliances in my kitchen. This includes a stainless steel sink, refrigerator and dishwasher. These appliances were already in the house when we moved in.

Stainless steel has been very popular for kitchen appliances the last few years and I love the modern look. The only thing I don't like about the refrigerator and the dishwasher is I find the fingerprints hard to clean off. No matter what type of cleaner I have used, it seems to leave streaks.

With three young kids in the house you can imagine the number of fingerprints I get on my refrigerator in a day.

As far as the stainless steel sink I really love it. It is so much easier to clean and I can really get it looking clean and shiny without much effort.

By Perdido — On Sep 04, 2012

My kitchen has a stainless steel sink. It looked pretty dull when we moved in, because it hadn't been polished in years, but my husband made it look brilliantly shiny.

He used an electric sander with a buffer pad attached to return the sink to its original state of bright silver. He buffed it in circles, so there was a light circular pattern left behind.

I never believed that the sink could look so shiny. I'm glad that he knew this trick, because I could have scrubbed for half an hour with a brush and would still have been unable to achieve these results.

By LisaLou — On Sep 04, 2012

@lamaestra-- I am also hoping they don't come out and say that stainless steel has harmful chemicals. I replaced all my plastic water bottles with stainless steel.

Hopefully the stainless steel won't leak out chemicals like they say the plastic does. I can tell a difference in the taste of my water. My water really does taste a lot better when it doesn't have that hint of plastic taste to it.

By anon173178 — On May 06, 2011

what are the engineering properties of stainless steel?

By sschwartz — On Jan 20, 2011

Stainless steel, like all metals, is a renewable resource. Metals are melted down and reused more than any other type of material.

By anon88997 — On Jun 08, 2010

I am in the process of buying a pvc fence for my backyard privacy type. However when I speak to different companies they have stated the PVC fences come in different grades some with mental at the bottom for sturdiness. Do different manufacturers make different fences have this mental inserts? Thank you. Lorraine

By anon57554 — On Dec 24, 2009

birgitte: You cannot add (plate) a layer of stainless steel. Stainless steel is an alloy and cannot be plated. A fairly reliable test for stainless steel is to use a magnet and compare how well it sticks to ordinary steel and the s/s metal you are testing. The higher grade stainless has no magnetic properties. The best magnet to test with is a rare earth magnet, which is the strongest magnet available.

anon21981: 18/8 stainless steel means 18 percent Chrome and 8 percent Nickel. Steel should only be called stainless if it has at least 10 percent chrome. Stainless steel is good for cooking but not for storing food. It is the oxygen in the air that keeps stainless steel from corroding and it will begin to corrode if covered continuously with food etc.

lamaestra: Stainless steel is not recommended for the storage of wet foodstuff. Too complicated to explain here.

By birgitte — On Apr 07, 2009

I am sanding my dishwasher to paint with black epoxy to match my new black and stainless steel appliances, but underneath the paint appears a beautiful brushed stainless steel surface, created by the fine grained sandpaper. So I am thinking: Why don't I just sand over the whole thing? Well, I did, and it looks great, but I am concerned about rust. I wonder if the metal panel is rust-resistant like stainless steel or if you have to treat it, and if that is even possible? Any ideas?

Based on this article I wonder if the metal in a dishwasher has enough chromium etc. and whether you can add a film of chromium on top?

By anon21981 — On Nov 25, 2008

I see a lot of food container specify made by 18/8 stainless steel, what is 18/8 stainless steel? Is it better than regular stainless steel? Does it harmful when use as food container for hot/cold?

Thanks.

By lamaestra — On Apr 22, 2008

Stainless steel, of course, is also now being touted and the material of choice for reusable water bottles, now that Nalgene and other plastic bottles have been found to have harmful chemicals. I hope stainless steel doesn't have harmful chemicals and I don't think it is too renewable...

What is Stainless Steel?

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