The UNS N09935 alloy with a minimum yield strength of 760 MPa (110 ksi) was successfully balloted in
NACE MR0175/ISO 15156-3: 2003 based on SCC test results in a test environment much more severe
than NACE Test Level V and on GHSC test results in NACE Test Level III. These results indicated the
suitability of this material for sour service applications. Further to these findings, an R&D test
programme has been implemented to investigate the corrosion resistance of UNS N09935 in more
severe conditions, beyond 200 °C. Properties of this material and results of this test programme are
herein presented and discussed.
Key words: 935 alloy, UNS N09935, corrosion resistance, HPHT sour environment