Layman Test to Differentiate 304 Grade Stainless Steel from 201 Grade

300 series has enough nickel in it so that it will not attract a magnet.

That's about all I know. Milo?????

Welcome to the in sanity. You are wise to find a way to determine the quality of the steel. I would also check for termite holes in their steel. Good luck.

What you really need is a way to determine how much mercury, lead, and cadmium is in that "steel ".

You can ask test certificate of used steel to check chemical compostitions and verify it by third party inspection agencies.

Dear Mr. Prashant VS,

Verifying the material composition from the Test Certificate is one aspect.

In addition to that there are certain destructive test for the sample and the sample piece is to be subjected to these tests and the results for these tests should be with in the limits of the standards. These tests are described in the Standards

Thanks,

DHAYANANDHAN.S, INDIA

I agree with you.

No issue.

Thanks.

Thanks Prashant, Are you saying I can ask the manufacturer for a a test certificate of the chemical composition of the stainless steel? Would a typical manufacturer normally/automatically have such a certificate or would he have to get one specially provided? I do not want to insult the manufacturer by asking him to get a special certificate - it suggests I dont trust him. What would be the right protocol to get such a certificate?

I do not want to insult the manufacturer by asking him to get a special certificate - it suggests I dont trust him. What would be the right protocol to get such a certificate?

You don't know the company. There's no reason for you not to check. If they are insulted, they may be covering up. Getting a test certificate is normal practice throughout the world. If you ever work for the government, you know they insist on knowing all about you, your finances, everything before doing business with you. They may even expect security deposit from you.

Dear Mr.raphaelkahn,

Stainless Steel Manufacture is covered by STANDARDS, for both CHEMICAL COMPOSITION and MECHANICAL STRENGTH, like Tensile Strength, Torsional Strength, Hardness, Grain Structure etc. and Manufacturers will have their own In-House Lab and the General Practise is the Test Certificate will be provided with the Consignment.

You need not feel shy and there is no insult in asking for the certificate to be provided, if the manufacturer is not providing. If you intend to witness the test, it can be or should mentioned in the order.

DHAYANANDHAN.S

The only way is to do a chemical analysis it can be done, by removing a piece or portable chemical analysis where you only have to clean an area to do a spark with out destroying the piece and then you compare it to a code or standard.

Both 300 and 200 series are austhenitic, meaning they are not magnetic, therefore a magnet test could not distinguish the two. However you could use a magnet to ensure that the chairs are not made out of 400 series (ferritic stainless). As far as the distinguishing between 200 and 300 series only a chemical or xray analysis would do the trick...may be worth express shipping a sample back to AUS to have it tested.

Thanks bvandedr Could you direct me to someone in Sydney, Australia I could go to, to conduct a chemical or xray analysis?

I am travelling, will be able to give you a better answer when i have my computer and better resources. Niton makes a portable analyzer. Its pricey, but you may be able to arrange a rental.

http://www.niton.com/rentals-and-leasing/rentals.aspx?sflang=en.

There may be difficulties as a carry on, and theft is certain if it is in your checked baggage.

I may be able to give you an inexpensive spot check analysis but for that i need to get back to my office. I am a carbon and alloy , not stainless steel, guy.

milo

I agree with your answer completely.

I'm not entirely sure why you would worry about a substitution of 201 Stainless Steel

It's more important that the material is Certified to UNS or AISI standards, as not all steels are steels.

Other substitutions, that lesser corrosion resistance, tend to be noticeably magnetic.

Agree completely that for this application, i.e. furniture structure, 201 is completely suitable. Your note and the link are right on. Since the original inquiry discussed T304 my assumption was that T304 was in the terms of his order for the chairs and would be the basis for settling on quality conformance. But I fully agree that it is not a critical requirement for functionality. Also, as you point out, whatever the analysis reveals as composition, it should show conformance to one or more of the accepted standards for austinitic stainless steel grades.

It's more important that the material is Certified to UNS or AISI standards, as not all steels are steels.

The problem here is the lack of ethics that some people have experienced when doing business with some countries. I am able to print certification forms all day long.

I would suggest having someone that can tell the differences between various stainless steels examine the product.

The chairs are for a waterfront function venue in Sydney, Australia. This is why 304 grade Stainless Steel was specified on the agreement.

Type 201 has enough chromium to consider it a corrosion resistant alloy typical for stainless steels. In my opinion, a harsh atmospheric environment such as may exist in a waterfront location would not generally dictate against its use there for furniture applications.

A lot of specific information regarding the intended use of the chairs would be needed to say more on that. For example, frequent immersion in salt water followed by removal with drying out leaving salt residues could produce pitting corrosion, however that can even happen with T304 stainless. If the chairs are to be used that way they should be thoroughly washed with clean fresh water after being in salt water.

Interesting comment, thank you! The chairs would be indoors but large balcony doors would often be open, allowing salt air to blow in and on the chairs. This is the worst case scenario. There is no immersion in salt water etc. Therefore I would conclude from your comments that 201 grade stainless steel should not be problematic if it were to be substituted for 304 grade.

I believe T201 would be suitable, i.e. low corrosion rate in the environment you described, but of course that is not a guarantee. It should be ok.

Remember, all materials have some rate of corrosion in their environmental exposure. The real question is what will be the length of the useful life for the chairs. My guess is that there would not be a great difference between the T201 and the T304. The defects in either case will likely be more cosmetic than structural failure.

However, since you ordered and paid for T304 you should follow up with your chair supplier to ensure that he provided it. If it is determined that the material was actually T201, it will not be too great a loss to you and perhaps a settlement could be made with the chair supplier without great risk to you.

Perhaps you can give us a report in a few years. It would make an interesting field test of corrossion resistance of the T304 (or T201) in that salty air.

Thanks for your sensible advice, joconco. I think you live up to your motto and I appreciate it. I shall diarise to follow up in about 2 years and let people know the outcome.

Interesting voting on this thread

[if it's not magnetic] Here is probably the 'test' you'd next want to consider