Identify some Stainless steel.

I have a bar of Stainless steel that has a red paint over the end, can anyone identify the grade from that colour?

It machines OK and the second question is, can I hard solder it?

Clive

Can't help with the colour/grade but I've silver soldeed stainless plenty of times, just use Tenacity No5 or Cup's HT5 flux.

J

I think that red indicates 416, a martensitic stainless steel with good machinability, but poor weldability as it includes sulphur and phosphorus. Silver soldering is not recommended, particularly if the joint is to be subjected to moisture.

Regards,

Andrew

Red Gloss is Humbrol No. 19 - I thought everyone knew that?

Seriously , I read a 90's ME with interviews of several steel stockholders and they all used their own coloutr codes and had done so since the Ark. It my be different today, though.

Neil

... and to add to Jason's comment, the only stainless I've ever silver soldered that was under load was for the ram of my 'Stan Bray' keyway slotting cutter. The joint ractured clean across in minutes, but luckily the backup taper pin is still going strong.

If you don't know what grade stainless it is, don't rely on silver soldering it.

Neil

Thank you for the heads up on the grade, it looks as if I will have to order some 304 instead.

Annoying as I have made the parts already.

Clive

Just a little warning. If you use silver solder, use the lowest melting point you can, a zinc-free solder, or use a special stainless steel grade of solder, such as Argobraze 56 (usual disclaimer). If you silver solder an austenitic stainless steel at about 700 deg C using a zinc rich solder, it is likely to crack due to zinc embrittlement. Remember Flixborough?

Edited By The Mad Professor on 26/07/2012 09:14:23

Edited By The Mad Professor on 26/07/2012 09:15:13

If the material is non-magnetic and machines easily probaly 304 if magnetic 416 or mild steel

I have given stainles steel springs a speck of silver solder to enable soft soldering electrical wires. Colin