Tungsten Fiber Reinforced Copper Matrix Composites: A Review.

Tungsten fiber reinforced copper matrix WCu composites have served as an ideal model system with which to analyze the properties of metal matrix composites. A series of research programs were conducted to investigate the stress-strain behavior of WCu composites the effect of fiber content on the strength, modulus, and conductivity of WCu composites and the effect of alloying elements on the behavior of tungsten wire and of WCu composites. Later programs investigated the stress-rupture, creep, and impact behavior of these composites at elevated temperatures. Analysis of the results of these programs has allowed prediction of the effects of fiber properties, matrix properties, and fiber content on the properties of WCu composites. These analyses formed the basis for the rule-of-mixtures prediction of composite properties which has been universally adopted as the criteria for measuring composite efficiency. In addition, the analyses allowed extrapolation of potential properties of other metal matrix composites and were used to select candidate fibers and matrices for development of tungsten fiber reinforced super- alloy composite materials for high-temperature aircraft and rocket engine turbine applications. This report summarizes the WCu composite efforts conducted at NASA Lewis Research Center, describes some of the results obtained, and provides an update on more recent work using WCu composites as high-strength, high-thermal-conductivity composite materials for high heat flux, elevated-temperature applications.