The effect of hydrogen on plain and notched test specimens of precipitation hardenable nickel alloys

Nickel alloys, Hydrogen Stress Cracking, Hydrogen Embrittlement, Oil & Gas downhole equipment, Slow Strain Rate Testing INTRODUCTION The Precipitation Hardenable Nickel alloy 718 (N07718) is widely used for critical downhole oil field applications such as high strength tubing hangers and complet...

Full description

Saved in:
Bibliographic Details
Published inNACE International Corrosion Conference Proceedings pp. 1 - 10
Main Authors McCoy, S A, Maitra, D, Mannan, S K, Crum, J R, Tassen, C S
Format Conference Proceeding
LanguageEnglish
Published Houston NACE International 01.01.2017
Subjects
Age hardening
Alloys
Aluminum
Chromium
Corrosion resistance
Ductility
Failure
Failure investigations
Glycerol
Grain boundaries
Hangers
Hardenability
High temperature
Hydrogen
Hydrogen embrittlement
Mechanical properties
Microscopy
Nickel alloys
Nickel base alloys
Niobium
Oil fields
Precipitates
Slow strain rate
Strain analysis
Stress concentration
Stress cracking
Superalloys
Tensile strength
Test methods
Titanium
Yield stress
Online AccessGet full text

Cover

More Information
Summary:Nickel alloys, Hydrogen Stress Cracking, Hydrogen Embrittlement, Oil & Gas downhole equipment, Slow Strain Rate Testing INTRODUCTION The Precipitation Hardenable Nickel alloy 718 (N07718) is widely used for critical downhole oil field applications such as high strength tubing hangers and completion equipment. Over the last 15 years a limited number of field failure investigations in PH Nickel alloys have been related to the presence of sufficient amounts of intergranular delta phase precipitates promoting hydrogen embrittlement, which results in brittle cracking of alloy 718 3,4 and alloy 7255. The general alloying principle for the PH Nickel alloys uses high levels of Nickel, Chromium and Copper for corrosion resistance and Nb combined with a controlled combination of Ti and Al to provide the age hardened strengthening mechanism. In this investigation a Slow Strain Rate testing method developed by the French Corrosion Institute(2) and a modified test method using a notched tensile specimen has been used to assess the susceptibility of PH Nickel base alloys to hydrogen embrittlement9.