Infiltration Processing of Tungsten-Reinforced Bulk-Amorphous Metal Matrix Composites

Abstract

ABSTRACTHigh-density tungsten (W)-reinforced bulk amorphous metal (BAM) matrix composites have been fabricated by a pressure infiltration methodology. A hafnium (Hf)-based BAM with a density of 11 g/cm3, glass transition temperature, Tg, of 495 °C, and liquidus temperature, Tliq, of 1,050 °C has been used to infiltrate open-porosity W-wire preforms to create W-Hf-BAM composites. Because of the considerably higher Tliq of Hf-based BAM alloys than those based on Zr, the interaction of the BAM with the fixture components, reaction with the W perform, and the formation of undesirable intermetallic phases in the composite were of primary interest. The roles of infiltration pressure, soak temperature, and time at temperature on the composite structure were examined. The structure and quality of the composites were determined with simple fracture tests, scanning electron microscopy, X-ray diffraction, and differential thermal analysis. The fabrication procedure steps and the characteristics of the composites are described.