Surface Tension and Density of Al-Ni Alloys

摘要: In the present work, surface tension and density of a set Al-Ni alloys have been investigated as function composition temperature. The measurements were performed by large drop method, under equilibrium with an oxygen-free surrounding atmosphere to prevent oxidation phenomena. study was focused mainly on Al-rich in framework EU FP7-IMPRESS project aimed obtain tailor-made nanopowders for high-performance macroscale catalytic devices. measured thermophysical properties compared both literature results data theoretically predicted applying thermodynamic calculation methods (e.g., QCA CFM), aim highlight role intermetallic compounds. Al-Ni-based expected be used high-temperature oxidation-resistant materials several fields, example, aeronautics, turbine blade production, space systems, automotive engineering, chemistry, hydrogen fuel cell technology, biomedicine. particular, attractive such low density, high strength, good corrosion resistance. 1 On basis binary phase diagram, 2 evidence is presented five compounds Al3Ni, Al3Ni2 ,A l 3Ni5, AlNi, AlNi3). Among these intermetallics, Al3Ni has gained considerable interest, recent years, applications, valuable alternative Raneytype nickel-aluminide (Al68.5Ni31.5) alloy. These differ from most other types catalysts since their area achieved selectively leaching away aluminum aqueous sodium hydroxide. Recently, AlNi extensively spite properties, based limited applications due extreme brittleness resulting difficulties shaping casting. For reasons, casting solidification modeling become indispensable tool development optimization Albased alloy technology. However, knowledge reliable key issue industrial processes. application numerical tools generally hampered lack property values. Thermophysical can divided into those relevant heat fluid flow. flow include thermal conductivity, specific capacity liquid solid phase, enthalpy fusion, fraction cooling. viscosity, together its temperature coefficient. Moreover, values important prediction defects bubble entrapment gas porosity well better understanding nucleation-condensation phenomena