Where the
world gathers for metal finishing
Q&As since 1989


-----

Heat treating 17-7PH Stainless Steel

Q. Can 17-7 PH condition A be heat treated to CH900/RH950?

Everardo Hernandez
Sierra Pacific Engineering and Products - Los Angeles, California
2004

---

A. Yes to the RH950 condition, no to the CH900 condition. The CH900 requires that the starting material be in the heavily cold worked condition, called condition C, and not the annealed or solution treated condition called A. Lee Gearhart metallurgist - E. Aurora, New York 2004 A. It may be possible to heat treat your article to RH950 or CH900, depending on exactly what you have. CH900 applies to 17-7 PH (Type 631) wire that has been previously solution annealed and then cold drawn, which is then aged for 1 hour at 900 °F (482 °C). If your article has not been cold drawn, then CH900 cannot be performed. RH950 is performed as follows: after solution annealing the article is heated for austenite conditioning, which consists of heating to 1750 °F (954 °C) then air cooling. Within 1 hour the article must be cooled to -90 °F (-68 °C) for 8-9 hours, then air warmed to ambient. The article is then aged for 1 hour at 950 °F (510 °C). Toby Padfield Automotive module supplier - Michigan 2004

---

---

Q. Can 17-4PH condition A be heat treated to CH900/RH950? I have a job that requires this process, I want to know if this is possible.

Felipe Gutierrez
Sheet metal Shop - Oxnard, California
2006

---

RFQ: Hi Guy's, Hi Girl's,
On the subject of 17-7PH I'm looking for very nice etched cross sectional micrographs or SEM's in longitudinal direction and at 90° to this. If possible of thin strip in condition A, Condition TH 1050 and RH 950.
I need them for educational purpose.
Thanks for your help.

Andy Blatter
- Rothenburg, Luzern, Switzerland
2007

Ed. note: Sorry, this RFQ is old & outdated, so contact info is no longer available. However, if you feel that something technical should be said in reply, please post it; no public commercial suggestions please ( huh? why?)

Q. IS 17-7 CONDITION C AND ANNEALED CONDITION THE SAME?
IF NOT, CAN YOU HEAT TREAT FROM ANNEALED CONDITION TO CONDITION C?

Carole Delacroix
alloys - Orange, California
July 15, 2008

Q. Hello,
I need the detailed steps of cold work of 17-7 steel. It is very work hardening alloy and it needs intermediate annealing processes. I don't know how it is possible to anneal this steel but it's final strength is not reduced.

zahede farzan
student - Tehran, Iran
May 12, 2009

---

Q. Does anyone have data on the resultant drop in hardness/tensile strength if 17-7 PH CH900 is overaged at 900 °F for periods greater than normal, say 6 or 12 or 24 hours? I am putting together some educational materials and this data would be helpful as a cautionary note.

Jim Kobrinetz
- Chicago Illinois USA
July 20, 2011

---

---

Q. Re: Heat Treating of Annealed 17-7PH sheet:
I have a request to harden a part to RH1020. Is this possible ?

JEFF MILLER
METAL PRODUCTS - Gardena, California
August 22, 2012

---

---

July 6, 2015

Q. Hi everyone.

I have a problem with the magnetic properties of 17-7PH wire springs.

Is there someone who can give me a clue about the main factor of magnetic properties in 17-7PH SS?
My wire condition is CH900 finished with 90% drawing ratio.
Due to a very small size of sample, I couldn't measure the martensite or delta ferrite volume fraction.

Regards,
SIHOTANG

Restu Sihotang
Wire Manufacture - Busan,Korea

----
Ed. note -- That's 7 unanswered questions in a row, folks. If you know enough about the subject to be able to post a reasonable question, you probably know enough to be able to help.