s275 grade steel

hi i need to make alot off inner surports that will never be seen so dont want to spend a great deal on bms so was wondering would i be able to use this grade of steel and still be able to drill and tap it succsefully just i can get 6m for cheap and money is tight so.......

atb mike

Hi Mike,

If someone is shifting stainless cheaper than BMS, ask why!

It appears to be a hardenable stainless steel but you have to register to get a full data sheet.

The patent says "Typically, the alloy of the present invention is solution annealed at about (927 C-1038 C) for about 1 hour and then quenched."

It is age hardened by "For example, the alloys are aged at a temperature between about 900 F
(482 C) and about 1150 F (621 C) for about 4 to 8 hours. The specific aging conditions used are selected by considering that: (1) the ultimate tensile strength of the alloy decreases as the aging temperature increases; and (2) the time required to age harden the alloy to a desired strength level increases as the aging temperature decreases."

You can make it even harder by then cooling it well below zero!

The patent says cold working makes it tougher - I suspect this is a careful way of saying its a b****d to machine even in the annealed state.

If you can get an annealed sample, the only thing to do would be to try machining a piece. I suspect it is meant to be cold-forged into things like knives pieces of spaceship or aeroplane, rather than machined, and then hardened in a furnace, so don't hold your breath.

Neil

Edited By Stub Mandrel on 29/09/2013 21:44:48

Stainless?

More likely to be a low carbon structural steel, supplied in hot rolled form. It machines ok, but it's a bit 'gooey' compared to EN1A. It's a bit more difficult to get a good finish. It normally comes in 6m lengths. However, sizing is not accurate, it is covered in mill scale, and you will need to machine all faces if you require accurate size and finish.

That's why it's relatively cheap. On the plus side it doesn't distort like cold drawn when machined.

Regards,

Andrew

hi thans for the info its not a big issue of surface finish as its hidden between 2 plates and once in will never be seen again its only to act as a spacer (dosent have to be overlly acurate) just needs 44 m5 tapped holes and about 70 holes for steel rivets in 1/8 diameter dosent matter if takes longer to do il just buy some new decent quality drills.......

Michael

I found this data regarding S275 steel with a quick search.

Cheers

Martin

Neil,

Do you reckon Carpenter might be an Alchemist ?

... or is this just a three-digit coincidence ?

MichaelG.

It does highlight that most of the time we only quote a small part of the full material designation - and sometimes that leaves room for doubt as to exactly what we talking about.

Not surpising that with the many steel types in existence, and many different methods to codify them, that there are some with common character strings in the designation.

As andrew says it the same spec as structural steel so not the nicest to machine take a look at someone like Parker steel and a lot of their structural sections are S275JR.

So weigh up the cost of a broken tap against the small extra cost of EN1A which is also a lot cheaper when bought in full lengths.

Edited By JasonB on 30/09/2013 07:46:25

I could have sworn the OP mentioned 'stainless'!

Neil

Edited By Stub Mandrel on 30/09/2013 09:58:26

Not as much as you swore when you realised he did not

that's what I edited out.

Neil

I used S275 for my side frames. It is ideal stuff to use, and machines, drills, taps, etc ok. This is the grade of steel normally supplied in black plate form for general steel work, and used for probably most structural steelwork in the UK. And also what most laser cutters use in the +3mm sizes of steel sheet. Best way is to find a stockholder who will sell you offcuts. If you can get "pickled and oiled", it is black steel plate that has had the black scale removed by pickling, so you get a nice piece of bright steel without all the distortion worries of using bright