Study to optimize Cr-Mo steels to resist hydrogen and temper embrittlement

Technical Report · Thu Aug 23 04:00:00 EDT 1979

DOI:https://doi.org/10.2172/5763699· OSTI ID:5763699

Johnson, E. W.; Shaw, B. J.

Hydrogen sulfide environmental tests on a 2-1/4 Cr-1 Mo sample are presented. The present emphasis is on modifying a testing technique for low yield strength steels (by approx. 100 ksi) in which (i) plane stress-plane strain and (ii) incubation time problems are severe. It is demonstrated that the plane stress zones pin the crack and that these zones can be eliminated by side grooving the specimen. The incubation time is reduced by pre-fatiguing in the environment. The reasons for using an arrest stress intensity value, from a simulated bolt load test (K/sub arr/), rather than a crack onset K, from a rising load test (K/sub 0/) for an assessment of hydrogen embrittlement susceptibility are given. It is shown in this sample that a smooth sided 3T specimen has a K/sub 0/ approx. 150 ksi in /sup 1/2/ whereas a side grooved 2T specimen has a K/sub arr/ approx. 20 ksi in /sup 1/2/.

• Research Organization: Westinghouse Electric Corp., Pittsburgh, PA (USA). Research and Development Center
• OSTI ID: 5763699
• Report Number(s): FE-3050-T2
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
CHALCOGENIDES
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-MOLYBDENUM STEELS
CORROSION RESISTANCE
CORROSIVE EFFECTS
CRACKS
CRYOGENIC FLUIDS
ELEMENTS
EMBRITTLEMENT
FLUIDS
HYDROGEN
HYDROGEN COMPOUNDS
HYDROGEN SULFIDES
IRON ALLOYS
IRON BASE ALLOYS
NONMETALS
STEELS
SULFIDES
SULFUR COMPOUNDS
TEST FACILITIES