The Influence Of Temperature,Substrate And Atmosphere On Surface Tension And Wettability Of FeSiB(Cu,Nb) Alloy Melt

Fe-based amorphous and nanocrystalline alloy have excellent magnetic properties including high permeability and low hysteresis loss,and the cost is low,so it is widely used in functional materials.Studying the surface tension and wettability of FeSiB(Cu,Nb)alloy melt with ceramic substrates are the base work for the production of amorphous and nanocrystalline products.Wetting behavior,interfacial interaction and surface tension play the key role in the process of preparing and processing materials.For Fe-based amorphous and nanocrystalline alloy obtained by rapid solidification techniques,studying the surface tension is meaningful.Contact angle and surface tension instrument is used to systematically measure the contact angle and surface tension of Fe78Si9B13 and Fe73.5Si13.5B9Nb3Cu1 melt at different temperatures.The relevance is explored between surface tension,contact angle and ceramic substrates by using BN,Al2O3 and SiC three kinds of ceramic substrates,and vacuum,N2 and Ar three kinds of protection atmospheres.The wetting process belongs to reaction wetting between three kinds of ceramic substrates and Fe78Si9B13 and Fe73.5Si13.5B9Nb3Cu1 melt at high temperatures.New phases are generated from the solid-liquid interface.The increasing temperature is helpful to improve the wettability.Compared to at inert gas atmosphere,the wettability reaches equilibrium more quickly in vacuum.Surface tension of the alloy melts will usually decrease with increasing temperature for the stable system.However,the interfacial reaction and the generated phases is revealed in this work to have a significant impact on the contact angle and surface tension,and finally leads to a more complicated results.The obtained data in vacuum are more stable than that in inert gas atmosphere,especially for the repeatability and accuracy.And this contrast will widen with compositions,reaction of solid-liquid interface and new generated phases.As the droplet contour is always not stable in Ar atmosphere,the surface tension of the melts is not accurate.Owing to the refractory nitride generated from N2 and molten alloys at high temperatures,the droplet contour always irregular,the contact angle and surface tension in N2 atmosphere can not be measured.The chemical reaction between Fe78Si9Bi3 melt and SiC substrate is the most evident with the thickest reaction layer,the smallest contact angle and the best wettability,on which the Al2O3 substrate is followed,and the BN is the worst.The decrease of contact angle is the fastest for Al2O3 substrate with increasing temperature,which is much slower for BN substrate,and is almost stable for SiC substrate.