We are professional 17-7pH Valve seat rings (UNS S17700, 1.4568, AISI 631, 17-7 pH) from china
17-7PH is a precipitation hardening martensitic stainless steel that combines high strength and hardness with good corrosion resistance. Its corrosion resistance in conditions TH 1050 and RH 950 is generally superior to standard hardenable chromium types 400 series stainless steels, but is not as good as chromium-nickel type 304. Corrosion resistance in condition CH 900 is similar to type 304 in most environments. Like other martensitic steels, it is subject to cracking when exposed under stress in environments containing hydrogen sulfide. Such applications should be avoided.
Applications: Aerospace industry, chemical and food processing equipment, petroleum refining equipment, and general metalworking.
Chemical composition
% | Fe | Cr | Ni | C | Mn | Si | P | S | Al |
min | balance | 16.0 | 6.50 | | | | | | 0.75 |
max | 18.0 | 7.75 | 0.09 | 1.00 | 1.00 | 0.040 | 0.030 | 1.50 |