What’s up guys? Michael with Metals in a Minute. Today it’s 17-4, Type 630, or UNS S17400 …. Whatever you choose to call it …… it’s a precipitation hardenable corrosion resistant “stainless” steel alloy.

Heat treatment consists of two steps….
First is a “solution treatment” or “solution anneal” at 1900 deg F that is later followed by a
“precipitation” or “aging” heat treatment in the range of 900 to 1150 deg F.

The result is a combination of strength and corrosion resistance used in many applications.

Highest strength is achieved at 900 deg F and designated as H900.
Solution treatment is commonly performed at the producing mill and the precipitation treatment during the manufacture of the component part.

Common aerospace material specifications are:
AMS 5643 for bars, forgings, tubing, wire, and rings
AMS 5622 for premium quality bars, forgings,tubing, wire, and rings
AMS 5604 for sheet, strip, and plate

Stay tuned for more 17-4! Don’t forget to Check the Specs.

For more info on 17-4 check out our 17-4 grade page.