..., which require high strength and corrosion resistance. Numerous subsea failures of these materials have been attributed to hydrogen embrittlement (HE) caused by hydrogen evolved by cathodic protection (CP) systems, and in the presence of geometrical design features, i.e. grooves, notches, threads etc...

...Abstract Hydrogen embrittlement susceptibility of precipitation hardened Ni-alloys is a complex function of several factors such as chemical composition, deformation mode, grain size and grain boundary precipitation of carbides and intermetallic phases. Understanding the role of these factors...

...ABSTRACT Limited evidence has been published which indicate that UNS N06625 (Alloy 625) is susceptible to hydrogen embrittlement. In this study we present new industry learning about how the performance of Alloy 625 is affected by hydrogen. Three different Ni-alloy 625 batches from different...

... applied potential was also studied to determine its effect on the measured parameters. Test Approach for Crack Growth Rate Testing Abstract Hydrogen embrittlement phenomenon has been investigated in the current study by performing crack growth rate (CGR) measurements under static and fatigue loading...

... to the hydrogen embrittlement resistance of Alloy 718. UNS N07718 Alloy 718 Hydrogen Embrittlement DCB Seawater Cathodic Protection INTRODUCTION UNS N07718 (Alloy 718) is an attractive material for use in subsea and downhole environments due to its combination of corrosion resistance and high strength...

...Abstract Precipitation-hardened nickel alloys (PHNAs) are widely used for demanding oil and gas subsea applications, because of their high strength and corrosion resistance. However, several failures were associated with hydrogen embrittlement, under cathodic protection (CP), as subsea CP systems...

...EXPERIMENTAL PROCEDURE Abstract This paper elaborates on a method previously reported that characterized a materials susceptibility to hydrogen embrittlement in a seawater environment under CP by monitoring the crack growth rate of ASTM ⁽¹⁾ E1820¹ pre-cracked CT specimens...

... OH − Abstract A preliminary analysis of failed prestressing strands within a post-tensioned tendon on the Wando River bridge in South Carolina showed signs of possible hydrogen embrittlement. One proposed source of hydrogen is through galvanic coupling that may exist between the galvanized steel...

...-17 3.0-4.5 - - 4-7 UNS N06690 58 min. 27-31 - - - - 7-11 Abstract Precipitation hardened (PH) nickel alloy UNS N07725 used in oil and gas subsea service have experienced several brittle fractures linked to hydrogen embrittlement (HE). The alloy’s susceptibility to cracking...

...Hydrogen Embrittlement Susceptibility Test In order to evaluate the hydrogen embrittlement susceptibility of the laboratory heats, SSRT tests were carried out with test specimens complying with NACE ⁽⁵⁾ TM0198-2011, ¹⁷ having a gauge section diameter of 3.81 mm (0.15...

...In this work the resistance against hydrogen embrittlement was tested by constant load technique on solution annealed materials and slow strain rate, SSRT, was performed in sour environment at NACE MR0175 / ISO ⁽²⁾ 15156 ⁶ Test level VI in cold worked condition in 140...

... subsequent adsorption and diffusion may lead to premature fracture. The present study investigated the influence of different UNS N07718 microstructures, obtained according to the API 6A CRA and ASTM B637 standards, on the hydrogen embrittlement susceptibility. For this purpose, a modified Incremental Step...

...Abstract Pure Titanium (Ti) can undergo Hydrogen Embrittlement (HE) in corrosive environments like sulfuric and hydrochloric acids as well as other chloride containing solutions such as Sodium Chloride solutions. Hydrogen plays a major role in the fracture process by forming hydrides which...

...Abstract Low Alloy steels (LASs) are, by volume, the most widely used alloy family in critical oil & gas (O&G) components. However, the strength and hardness of LASs for sour environments are limited to prevent different forms of hydrogen embrittlement, such as hydrogen stress cracking...

... is proposed. DCB constant load SENT hydrogen embrittlement INTRODUCTION For many decades several standardized and not standardized methods based on different pre-cracked specimen geometries have been used for quantifying the stress intensity threshold K_Ith under environmentally assisted cracking...

...Abstract The hydrogen embrittlement susceptibility of several UNS N07718 microstructures was determined with different in situ testing techniques. Hydrogen-affected stress intensity factors for crack initiation and for unstable crack growth were determined through incremental step load...

...°C. Other hydraulic systems (Fluid C) using a different inhibitor package had not experienced any similar failures as of the incident field investigation. Hydrogen embrittlement (HE) was considered as one possible cause of the observed cracking. In this work, multiple electrochemical tests were...

... during electrochemical charging. In addition, the slow strain rate (SSRT) method was used to determine the steels resistance to hydrogen embrittlement in terms of ductility ratio and time to failure. Permeation tests were used to characterise the hydrogen diffusivity and apparent solubility, whilst...

...) in hot and sour brines. However, evidence shows that they are susceptible to hydrogen embrittlement (HE) at low temperature. Failures of 718 (UNS N07718), 625+ (UNS N07716) and 725 (UNS N07725) in service have been attributed to HE. ^{1 - 3} In the case of 718, the failures have been attributed...

..., and environmentally assisted cracking resistance. However, unexpected cleavage failures of subsea components have been associated with hydrogen embrittlement (HE), calling into question the assumed superior properties of these alloys. Recent findings have linked the PHNAs’ HE field failures with the precipitation...