1. Home
  2. ⏣ General Metalworking
  3. 17-7 PH stainless magnetic?

17-7 PH stainless magnetic?

I'm having trouble finding out about the mill-supplied condition of 17-7 PH stainless. The issue is a complicated one but it could be answered if anyone has a piece of 17-7 PH stock and a magnet. If so, is it magnetic?

It can go either way; it depends on whether the stainless was left in the mill-rolled condition before heat treatment. 17-7 PH is a "semi-austenitic" grade that becomes martensitic (and thus magnetic) when it's cold-worked. If it's magnetic, it was mill-rolled or otherwise cold-work and then solution treated. If it's not, it was annealed in between those two steps.

Thanks, if anyone has a piece of the material and can see if a magnet sticks to it.

-- Ed Huntress

Reply to
Ed Huntress
Loading thread data ...

The bar of 17-9 PH I have from McMasterCarr is very magnetic. It's in the H900 state.

Reply to
oldjag

Hookay. Do you order this stuff regularly? If so, do you specify the H900 condition, or does it just come that way if you order 17-9 PH with no other specification?

That's what I'm trying to find out. I'll try to find a good supplier when I get to it and ask, but somebody's asking me what the "normal" condition of the stuff is, as it's delivered by the mill, if you just specify 17-7 PH. I haven't handled the stuff for over 20 years and I don't know.

Thanks for that info, though, regardless.

-- Ed Huntress

Reply to
Ed Huntress

I don't have a piece, at least not one that I'd trust the ID on. But according to an Armco pamphlet I have here, 17-7 comes from the mill in either condition A or C. A is mill annealed and non-magnetic, C is heavily cold worked and magnetic. Condition C is required as a starting point for treating to Condition CH900, which is the state with highest tensile properties.

Reply to
Ned Simmons

I wanted the H900 condition as it being used for a tool to cut mild steel bolts, screws etc. underwater. McMaster seems to have it in most flavors, probably at a bit higher price than if you purchased from a steel supplier in quantity.

Reply to
oldjag

McMaster gets some clinkers.

I ordered some 4140 bar stock, supposedly annealed. Machined rather poorly. Made the part, delivered to the happy customer. It was a one off gib that had been lost on a BP size mil (KO)l. I was in a hurry.

Well it finally bugged me to the point of measuring the hardness. IIRC it was ~20Rc, not quite pre-hard, but much harder than annealed. McMaster can't measure every incoming part, so I don't blame them, but shit happens. DJ

Reply to
Mechanical Magic

Aha! That's exactly what I need. Thanks, Ned.

-- Ed Huntress

Reply to
Ed Huntress

On Mon, 25 Feb 2008 21:36:37 -0800 (PST), with neither quill nor qualm, Mechanical Magic quickly quoth:

So tell McMaster and have them ask their supplier to replace your cutter--at the supplier's cost.

-- Such is the irresistible nature of truth that all it asks, and all it wants, is the liberty of appearing. -- Thomas Paine

Reply to
Larry Jaques

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.