17-4PH H1150 vs 17-4PH HH1150 or double aged
17-4PH H1150 vs 17-4PH HH1150 or double aged
(OP)
Hello,
We are looking for the difference between the two materials with regard to internal stress after machining, hardness properties and corrosion properties.
We typically purchase the material in the H1150 and machine the part in the H1150 condition. We do the same with the H900 condition also.
Our supplier only offers the Annealed state, so they drop ship to a heat treatment facility that has proven to be unreliable to delivery...etc. So we have been search for an alternative supplier. We may have found one, but they double age the or HH1150 the material. Is there a benefit we are missing or a setback in the bushes?
We use the material in a wide variety of process industries. Many of which require design review for a material change if a replacement part is offered.
Any insight into the double aging of 17-4PH is appreciated.
Thank you in advance.
Paul
We are looking for the difference between the two materials with regard to internal stress after machining, hardness properties and corrosion properties.
We typically purchase the material in the H1150 and machine the part in the H1150 condition. We do the same with the H900 condition also.
Our supplier only offers the Annealed state, so they drop ship to a heat treatment facility that has proven to be unreliable to delivery...etc. So we have been search for an alternative supplier. We may have found one, but they double age the or HH1150 the material. Is there a benefit we are missing or a setback in the bushes?
We use the material in a wide variety of process industries. Many of which require design review for a material change if a replacement part is offered.
Any insight into the double aging of 17-4PH is appreciated.
Thank you in advance.
Paul





RE: 17-4PH H1150 vs 17-4PH HH1150 or double aged
In the US, 17-4PH material is widely available, and heat treating it to H1150 condition is not complicated and there are dozens of competent vendors that can do this work. So I don't understand why you have a problem. The potential risk and liability from making a material change just to accommodate one particular material supplier does not seem justified in this particular situation.
RE: 17-4PH H1150 vs 17-4PH HH1150 or double aged
You should be ordering the HT to a specification (perhaps use the AMS) and there should be no room for deviation from that. This isn't a difficult HT, finding a responsible vendor should be straight forward.
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P.E. Metallurgy, Plymouth Tube
RE: 17-4PH H1150 vs 17-4PH HH1150 or double aged
there is a status called H 1150M which is treated at 1400F/2hr, air cool, then 1150F/4hr air cool. This is for the best machinability with higher elongation and much higher impact strength, compared with single aging H1150.
It makes no sense aging the same twice.
RE: 17-4PH H1150 vs 17-4PH HH1150 or double aged
Thank you all for your insight into my query. All the comments are very helpful in explaining the obvious to the untrained mind and gaining some knowledge along the way.
May my next metals thread provide a little more comic relief and less, really?
Enjoy the spring!
MECOMAN