Stainless steel is widely used in furniture production, for example, in the industry of designer furniture reproduction that we’re doing in, the frame of furniture like Barcelona chair is made of stainless steel. Some factories use 304# stainless steel while some use 201# stainless steel. The purpose of this post is to discuss the difference between them.
Firstly, let’s see the definition of stainless steel. Stainless steel is a term used to refer to several different metals that are commonly used in industries including transportation, construction, and even architecture. While all stainless steels contain more than 50% iron and at least 11% chromium, each grade has a different composition of other metals, giving it unique properties, strengths, and weaknesses
After knowing the common point of 304# and 201#, let’s analyze their differences:
Generally, the price of 201# is lower than 304#.
By the situation of the continuously rising prices of nickel, stainless steel products which contained low nickel content, low prices is really attractive. And the 201 stainless steel is a suitable choice. Grade of 201 stainless steel is gaining large of market, where 304 stainless steel and 301 stainless steel are the main choice. 201 stainless steel has a low and stable prices because it uses Magan alternative to Nickel. So, it makes 201 stainless steel has many similar properties and characteristic as 304 stainless steel and has an appearance as same as 304 stainless steel appearance.
The stainless steel is a type of steel that contains more than 11% chrome, so stainless steel has a film self-protect against corrosion. Nickel also known as the main factor to bring stability to the Austenitic phase and capable of easy processing to stainless steel.
304 stainless steel has a minimum content of Nickel of 8%. In elements which formed to Austenitc, there are many elements can substitute for Nickel to create resistance to corrosion. For example: Chrome (Chrome is the main elements that makes corrosion resistance of stainless steel), Manganese (also contributes to stable Austenitic phase), Nitrogen also contribute to hardness, Copper (Cu) also contributed to Austenitic phase stability.
In 201 stainless steel, Manganese was used as the main element to replace Nickel in a 2:1 ratio. We can see by the following chemical composition:
+ Stainless steel 201: 4.5% Niken and 7.1% Mangan
+ Stainless steel 304: 8.1% Niken and 1% Mangan
With this composition as above have reduce the raw cost material to produce a 201 stainless steel. This is a first advantage of 201 stainless steel.
- Durability and capable processing
Density of 201 stainless steel is lower than 304 stainless steel but the durability of 201 stainless steel is higher 10% then 304 stainless steel.
Due to the ability to stretch is the same with 304 stainless steel, 201 stainless steel is similar properties as 304 in the process of bending, shaping and flattening. But in another way, Stainless Steel 304 is still more flattening than 201 stainless steel. (This is due to the effects of Manganese element on 201 stainless steel, and it makes 201 stainless steel harder than 304 stainless steel)
Ref from http://www.worldstainless.org, it notices that: The 200 series is austenitic metal. More specifically, ‘201′ is made up of 16-18% chromium, 3.5-5.5 % nickel, 0.15% carbon, and 5.5-7.5% manganese. The 200 series is a high performance stainless steel. The 200 series has a higher tensile strength than the 300 series, which allows it to be thinner. For example, the Barcelona chair from Sparkle Furniture uses 201 stainless steel and its thickness is 10mm, while some others use 304 stainless steel and the thickness is 12mm. In a word, the 200-series grades are generally stronger and harder than the 300-series. This can be quite significant and useful in some applications.
- Corrosion Resistance capable comparison
When we compare the chemical content of 201 stainless steel and 304 stainless steel show the lower Chrome in 201 stainless steel than 304 stainless steel is about 2%. This makes the corrosion resistance of 201 stainless steel is lower than 304 stainless steel.
Surface pitting resistance is determined mainly by Chrome elements and Sulfur (S). Chromium makes stainless steel more resistant to corrosion, while the Sulfur reduces the resistance of corrosion. In chemical content, 2 kind of Stainless Steel has the same rate of Sulfur element. So pitting resistance on the surface of 201 stainless steel is lower than 304 stainless steel.
This image is the result of spray salt water through 575 hours. This dis-advantage makes 201 stainless steel should never in use maritime industry.
- Surface color
201 stainless steel contains higher Manganese and this element causes the towel rack surface more dark, but this difference is too tiny and users may not be able to tell, especially for mirror polished frame.
In conclusion, 201 stainless steel has lower price, better durability and hardness, while 304 stainless steel has higher price, and better corrosion resistance.
How can I tell if my stainless steel products made of 201# or 304# ?
There are several methods to tell if one Barcelona chair frame is actually made of 304#,
1) Use a magnet. 201# has stronger magnetism due to the higher manganese containing.
2) Use a knife to scratch the surface, 304# made product is more difficult to get scratched.
3) Find some professional test liquid, different materials will cause difference chemical reaction.
4) The most professional method is to use a Spectroscopic detector, end user may not be able to find this tool conveniently.
Be careful, someone may pass 201# made Barcelona chair frame off as 304# made, and charge you higher price.
Sparkle Furniture provides Barcelona chair with 201# stainless steel, which is durable, hard and having a competitive price. Honestly speaking, if you’re not going to use this chair in marine environment, it’s no big difference between 304 and 201. Because who would put their Barcelona chair in home into corrosive liquid and air? Most people’s living condition will guarantee this chair’ long-term good performance! But if you’re going to buy a chair for your yacht, please do choose Barcelona chair made of 304# stainless steel although it’ll cost you much.