|About this Abstract
||2011 TMS Annual Meeting & Exhibition
||Bulk Metallic Glasses VIII
||Measurement of Viscosity of a Metallic Glass in the Inaccessible Temperature Region Using Rapid Joule Heating
||Georg Kaltenboeck, Joseph P. Schramm, Marios Demetriou, William L. Johnson
|On-Site Speaker (Planned)
The lifetime of metallic glasses in the temperature region of the crystallization nose is so short that conventional heating techniques are far too slow to allow for the measurement of liquid properties. Therefore, a lack of physical data exists for metallic glasses in this temperature region. For example, a wide gap in the temperature-dependent viscosity exists around the crystallization nose even for the most robust glass formers. Recently, a novel joule heating method was developed that utilizes the unique electrical properties of the metallic glass to rapidly and uniformly heat to any temperature within the undercooled liquid region. Heating rates as high as 10<SUP>6</SUP> K/s were achieved, which enable the complete bypass of crystallization during the heating phase. Using parallel plate rheometry in combination with this heating technique, the viscosity of Zr<SUB>41.25</SUB>Ti<SUB>13.75</SUB>Cu<SUB>12.5</SUB>Ni<SUB>10</SUB>Be<SUB>22.5</SUB> was measured around the crystallization nose over a range inaccessible with conventional heating methods due to crystallization.