Analysis of Formability of Glassy Alloys by Surface Heating Under Convective Conditions

Modification of surface films by focussed energy sources with convective boundary conditions is idealised. The problem is approached by linearizing a coupled set of heat and mass transfer equation. The nonlinearity of the coupled problem introduces many complexities and exact solutions are not available in the general case. This work uses certain transformations not published earlier to obtain tractable solutions and stability benchmarks in terms of macroscopic parameters like the Stefan, Biot and Fourier numbers. Linear ODE’s are obtained from the coupled mass and heat transfer equations, which are analysed easily. Evaluation of the properties of the thermal boundary layer and attenuation with imposed fluctuating heat source shows that a regime exists for glass formation. Data from various alloy systems show that glass formability is related to the derived boundary layer thickness and certain non dimensional parameters.