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.
Yeah, McMaster Carr has nice little summaries under a variety of
headings--bearings, bronzes, drill rod, screw types, etc. A nice touch,
formerly Droll Troll
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.
Take that up with Joslyn-------I'm simply repeating *exactly* what their
product data sheet says:
"Joslyn 17-4 PH should never be put in service in Condition A (Solution
Interestingly, Jorgensen's stock book agrees with what Joslyn says.
I have to assume they know more about their product than you do.
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.
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.
Had they worded their comments differently, I'd likely agree-------but in
this case, unlike all others that I have read, it distinctly says to not put
it in service in solution annealed condition. All other stainless specs
I've read caution that the material at hand may be lower in corrosion
resistance in the annealed state, but there is no recommendation that they
not be put in service. Curious, isn't it!
Yes indeed. I have an Armco product data brochure from 1978
that contradicts your reference. Here's the same brochure
updated a bit...
On page 4 it says,
"This alloy exhibits useful mechanical properties in
Condition A. Tests at Kure Beach, NC, after 14 years show
excellent stress corrosion resistance. Condition A material
has been used successfully in numerous applications.
The hardness and tensile properties fall within the
range of those for Conditions H 1100 and H 1150.
However, in critical applications, the alloy is used in the
precipitation-hardened condition, rather than Condition A.
Heat treating to the hardened condition, especially at the
higher end of the temperature range, stress relieves the
structure and may provide more reliable resistance to
stress corrosion cracking than in Condition A."
Thanks for the updated data. I think the last sentence explains it
pretty well. I'd suggest it *can* be used in the solution
By the way, at the bottom of my sheet, it mentions that 17-4 PH is a
registered trademark of Armco Steel Corp. I would think their information
would be correct.
I found the following reason for the warning against using 17-4 in
condition A, in the ASM Metals Handbook, 8th edition, Volume 2 Heat
Treating, Cleaning, and Finishing. Page 249 preface " 17-4 PH is
normally supplied in the solution treated condition, in which it has an
essentially martensitic structure and has limited formability.
Fabrication .....bla,bla,bla " "This alloy should not be put into
service in any application in the solution treated condition, because in
this condition its ductility can be relatively low and its resistance to
stress corrosion cracking is poor. Hardening to any of the strength
levels shown in table 7 (H900 to H1150) improves both toughness and
resistance to stress corrosion.
Interesting, is that the following section on 17-7 PH makes no such
mention of warning in condition A.
Compounding the confusion further as MIL-HNBK-5J " Metallic Materials
for Aerospace Vehicle Structures" warn with the use of 17-7 PH in
condition A, but not 17-4.
In any case, I stand corrected, and Harold wins the cigar.
I'm willing to split the cigar with you, Tom. Thanks for the great
report! It's always been a mystery to me what the reason might
be------but I've always been quick to make mention of the
caution-------*just in case*. Better to err on the safe side I always say.
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.
"I've got more trophies than Wayne Gretsky and the Pope combined!"
- Homer Simpson
Website @ http://webpages.charter.net/dawill/tmoranwms
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.
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
: 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,
"Steamboat Ed" Haas : Yet another genius
Hacking the Trailing Edge! : without a job...
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