Most magnetic stainless?

All 300 series are not magnetic.

All 400 series are magnetic. 416 is free machining, machines similar to drill rod. 440 is much harder (even anealed) but workable.

I have also machined PH17-4 (also know as 630) and it is truely tough stuff. I don't like machining it. I have discovered that good carbide endmills (Atrax) make it feel like you are cutting aluminum!

See mcmaster catalog for a brief but good description of various SS.

chuck

Might be a good idea to suggest how you'll use it. It might dictate the proper alloy. Some, like 17-4 PH, are advised to not be put in service in the solution annealed condition, so heat treat could be necessary if you choose that alloy.

Harold

Yeah, McMaster Carr has nice little summaries under a variety of headings--bearings, bronzes, drill rod, screw types, etc. A nice touch, imo.

If you need somthing to stick to it, like refrigerator magnets, why not use any thin stainless, and put a sheet of mild steel behind it?

Jon

In the annealed state they are non magnetic. They are magnetic when work hardened.

I have discovered that good carbide

There is absolutely no reason not to use 17-4 in the annealed state other than being slightly softer and weaker than in the heat treated state. Even in the annealed state it is very strong.

See

Most of the 300 series SS's are non-magnetic, but some are, like 310.

17-4 and 15-4 are also magnetic, but I am not sure to what extent.

Interestingly, Jorgensen's stock book agrees with what Joslyn says.

I have to assume they know more about their product than you do.

Harold

snip---

Not in the annealed condition it isn't, Ernie.

Quite magnetic. I have considerable experience with them.

Harold

Does Joslyn say why 17-4 should not be placed in service in the Annealed condition?

Dan

Harold and Susan Vordos wrote:

(Solution

No, they make no mention of a reason, and I've yet to read one anywhere else. I'm as curious as anyone---I have a considerable amount of the material, a gift from a friend that closed the doors on his shop for health reasons. I use the hell out of it, but it's very easy to heat treat, so I do so. If, by chance, you happen to discover anything pertaining to the material, I'd be keenly interested in hearing from you.

It's strange material to machine, but once you're on to it, it's a pleasure to work with.

Harold

I'm just guessing here, but it looks like it must be in a supersaturated condition, with heating releasing the solute as precipitates, hardening it. This compares to aluminum that's halfway heat treated, since aluminum also precipitation hardens. I would guess it gradually ages at room temperature, possibly warping in the process, but this begs the question of shelf life; or perhaps the stresses cause trouble.

Tim

-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @

I find this very interesting, do you have a link? I have an old Jorgensens book that I will have to dig out, but I never heard of Joslyn. I have always used an old NASA research booklet as my guide for heat treatment and properties of all the precipitating hardening stainless steels. 17-4 is real amazing stuff. It cuts with a fantastic finish, drills easier than 304 or 316, and heat treats simply at 900 degrees F for the H900 properties which I do in a small dental vacuum oven.

Its corrosion resistance is not very good in the solution treated condition. If corrosion resistance is not an issue then I don't see any reason not to use 17-4 before hardening, but if you don't need the corrosion resistance or strength there are much cheaper alternatives.

Ned Simmons

Thanks, I have some remnants that I use sometimes. Fortunately the heat treat is very easy so I will do that whenever corrosion resistance or strength is a factor.

Dan

Ned Simm> > > Does Joslyn say why 17-4 should not be placed in service in the

Harold and Susan Vordos wrote: : Might be a good idea to suggest how you'll use it. It might dictate the : proper alloy. Some, like 17-4 PH, are advised to not be put in service in : the solution annealed condition, so heat treat could be necessary if you : choose that alloy. --OK here's the thing: like most folks I've got a truck with a totally inadequate glove compartment. What I've done is glue a strip of CRS to the dashboard. I went down to the local TAP Plastics store and got a couple of those square transparent boxes, maybe 1-1/2" square and tall enough to hold plastic spoons, toothpicks, etc; i.e. the things one always needs on long drives. I plunk a super magnet in the bottom of each one, put it on the steel strip and presto: I'm organized. Now the steel is totally rusted out and gunk is everywhere. Enter stainless, exit mess, yes? :-)

That'd work. Galvanized strap might work as well or better, though it might not look as cool.

Sorry, no link. All I have is a photo copy of the literature, which I have already scanned, so you're welcome to it if you're interested. Contact me on the side if you wish and I'll forward it to you.

Like you, I find it very nice to machine. It's a bit tough on carbide when roughing, but then all stainless aside from the free machining grades are. The finishes are outstanding, and even heat treated, it still machines quite well, although in the H900 condition it can be a bit challenging.

I use a burnout oven for heat treating small items, but I have a large electric heat treat oven (23KW) that I will eventually get installed for larger items.

Harold