THERMAL-STABILITY OF PD-BASED METALLIC GLASSES EXAMINED BY ELECTRICAL-RESISTANCE MEASUREMENT

Thermal stability of some Pd-based metallic glasses was investigated m ainly by the electrical resistance measurement. Differential thermal a nalysis was also performed to compare the thermogram with the electric al resistance curve. The crystallization and glass transition temperat ures were in good agreement between both measurements. The influence o f gas atmosphere on the electrical resistance curve was examined under a purified At and a vacuum state. The amount of oxygen impurity was l arger for Ar than vacuum. From the electrical resistance behavior in t he supercooled liquid region it was concluded that the thermal stabili ty of metallic glasses which contain Pd and/or B atoms was obviously a ffected by the oxygen impurity in the Ar atmosphere. Samples which wer e annealed to a temperature in the supercooled Liquid region under an Ar atmosphere showed the precipitation of nano-crystallites.