Hydrogen induced fracture characteristics of single crystal nickel-based superalloys. Final report, 19 June 1989-18 June 1990

Technical Report · Fri Jun 01 04:00:00 EDT 1990

OSTI ID:6521398

Chen, Poshou; Wilcox, R C

A stereoscopic method for use with x ray energy dispersive spectroscopy of rough surfaces was adapted and applied to the fracture surfaces single crystals of PWA 1480E to permit rapid orientation determinations of small cleavage planes. The method uses a mathematical treatment of stereo pair photomicrographs to measure the angle between the electron beam and the surface normal. One reference crystal orientation corresponding to the electron beam direction (crystal growth direction) is required to perform this trace analysis. The microstructure of PWA 1480E was characterized before fracture analysis was performed. The fracture behavior of single crystals of the PWA 1480E nickel-based superalloy was studied. The hydrogen-induced fracture behavior of single crystals of the PWA 1480E nickel-based superalloy was also studied. In order to understand the temperature dependence of hydrogen-induced embrittlement, notched single crystals with three different crystal growth orientations near zone axes (100), (110), and (111) were tensile tested at 871 C (1600 F) in both helium and hydrogen atmospheres at 34 MPa. Results and conclusions are given.

• Research Organization: Auburn Univ., AL (USA)
• OSTI ID: 6521398
• Report Number(s): N-90-26108; NASA-CR--183992; NAS--1.26:183992
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
BEAMS
CHEMICAL REACTIONS
CLEAVAGE
COMMINUTION
CRYSTAL GROWTH
CRYSTAL STRUCTURE
CRYSTALS
DOCUMENT TYPES
ELECTRON BEAMS
EMBRITTLEMENT
FRACTURE MECHANICS
FRACTURING
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
HYDRIDATION
LEPTON BEAMS
MATERIALS
MECHANICS
MICROSTRUCTURE
MONOCRYSTALS
PARTICLE BEAMS
PROGRESS REPORT
TEMPERATURE DEPENDENCE