Thermal cycling damage accumulation processes in an advanced metal-matrix composite

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1991

OSTI ID:5700220

Armstrong, W D

The response to thermal cycling of a set of W-1% ThO{sub 2} reinforced Fe-25Cr-8Al-.50Y superalloy matrix composites was studied. During this research, unique composite materials were produced by powder-metallurgical processing. These materials were three aligned composites of differing reinforcement aspect ratio, and a hierarchic composite that included fine-diameter Al{sub 2}O{sub 3} fibers. After HIP processing, specimen blanks were cut from the HIP billets by abrasive water-jet after which specimens were turned using a conventional engine lathe. The specimens were then thermal sprayed with an oxidation resistant FeCrAlY coating identical to the matrix material. The specimens were then thermal cycled between 1,100 C and 352 C and between 1,100 C and 534 C for 100, 500, or 750 cycles on a specially built thermal cycling machine. It was found that the initial longitudinal growth per thermal cycle was small. After many thermal cycles, however, the longitudinal growth per thermal cycle became much larger. The experimental results were analyzed using a new micro-mechanics model. It was found that the predictions of the model agreed with experimental data from the W-FeCrAlY, the W-Cu, and the SiC-Al composite systems.

• Research Organization: Washington Univ., Seattle, WA (United States)
• OSTI ID: 5700220
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ACTINIDE COMPOUNDS
ALLOYS
ALUMINIUM ALLOYS
CHALCOGENIDES
CHROMIUM ALLOYS
COMPOSITE MATERIALS
DAMAGE
ELEMENTS
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS
MATRIX MATERIALS
MECHANICAL PROPERTIES
METALS
OXIDES
OXYGEN COMPOUNDS
REINFORCED MATERIALS
THERMAL CYCLING
THORIUM COMPOUNDS
THORIUM OXIDES
TRANSITION ELEMENTS
TUNGSTEN
YTTRIUM ADDITIONS
YTTRIUM ALLOYS