|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Bulk Metallic Glasses XIII
||Assessing the Critical Casting Thickness via High-speed Thermography
||Fabian Haag, Jörg F Löffler
|On-Site Speaker (Planned)
Processing of bulk metallic glasses (BMGs) is limited by the temperature interval in which the alloys are in their so-called supercooled liquid range (SCLR). The commonly short period in the SCLR can be considered the processing window, i.e. the time before crystallization occurs. Processing of BMGs is frequently carried out from the molten state maintaining high cooling rates to quickly pass the SCLR and freeze the amorphous structure, e.g. by copper-mold casting. However, detailed information about how the high cooling rate affects the melt flow behavior during casting – and vice versa – is lacking.
We present the prerequisites to monitor quantitative cooling curves by high-speed infrared thermography. Using low-Tg Au-based BMGs, we discuss the cooling curves for fully amorphous, partly amorphous and crystallized regions of cast parts. The proposed technique allows studying crystallization during casting in dependence of the processing history, i.e. overheating and casting temperature.
||Planned: A print-only volume