Nondestructive Evaluation of Metal Matrix Composites.
Abstract
The objective of this program was to apply nondestructive evaluation (NDE) methods to identify potentially harmful casting defects in FP/magnesium composites; establish detectability and reproducibility limits of NDE applied to FP/magnesium composites; and establish relationships between casting defects and failure modes of FP/magnesium composites. The material investigated was ZE41A magnesium alloy reinforced with FP (aluminum oxide) fibers. The 27 coupons (four coupons each of five flaw types and seven coupons from a related program were evaluated using ultrasonic scanning, wave propagation velocity, and wave attenuation inspection techniques. The coupons evaluated were 12.7 cm (5 in.) long x 3.8 cm (1.5 in.) wide x 0.6 cm (0.25 in.) thick, with a fiber volume fraction of 0.50. After the detectability and reproducibility NDE inspections, tensile and/or bend specimens were machined from the parent coupons, strain gaged, and statically loaded to failure. Micrographs were made of the fracture surfaces for comparison with the NDE records. It was found that ultrasonic scanning using a 20 MHz compression wave, focused transducer operated in the pulse-echo mode generating an analog C-scan provided 100% detectability and reproducibility of the intentionally flawed coupons. Keywords: Metal matrix composites; Nondestructive testing; Nondestructive testing; Magnesium; Fiber reinforced composites; Castings; and Aluminum oxides.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1985
- Accession Number
- ADA166774
Entities
People
- G. M. Koller
- J. W. Adams
- S. W. Schramm
Organizations
- IIT Research Institute