An Investigation of the Structure and Mechanical Properties of High Temperature Glassy and Microcrystalline Alloys

摘要

This research had two aims: (a) development and characterization of high Tg (or Tx) glassy alloys, and, (b) identification and development of glassy Fe, Ni and Co base alloys which are capable of undergoing crystallization to a ductile, superfine grain size (less than about 0.1 micrometer), hot workable alloy product. In the first instance the Ni60Nb40 and Ni85Nb15 composition ranges were studied for glass formation, crystallization and properties. Alloying studies were undertaken to increase Tg(Tx) and to strengthen and stabilize the glassy state. In the second instance, compositions and glass forming tendencies were studied whereby the lowest possible metalloid content could be achieved while still producing a glass. For example, the classical Fe80B20 composition can be kept in the glassy state during melt spinning for compositions as low as 12-14 at. pct. boron. (Author)