Real-time in situ synchrotron X-ray tomographic microscopy was used to gain new insights into and quantify the nucleation mechanisms and growth kinetics of b-Al5FeSi intermetallics during solidification of an aluminium Al–7.5Si–3.5Cu–0.6Fe (wt.%) alloy. Three new insights were obtained. First, the plate-like b-intermetallics appeared to nucleate mainly on or near the primary aluminium dendrites...

Solidification needs an undercooling to drive the solidification front. If large undercoolings are achieved, metastable solid materials are solidified from the undercooled melt. Containerless processing provides the conditions to achieve large undercoolings since heterogeneous nucleation on container walls is completely avoided. In the present contribution both electromagnetic and electrostatic...

This article deals with a method of obtaining materials in the Ti-Al system. Research was carried out in accordance with the phase diagram of the system state. It was established, that both single-phase and multiphase systems, containing finely dispersed intermetallic compositions of phases Ti3Al, TiAl and TiAl3, are formed. Additionally, it was found that the pure finely dispersed (coherent-sc...

This study investigates the formation of a chromate conversion coating at Al-Cu-Fe-Mn intermetallic sites of an Al2219 alloy and the corrosion initiation at these sites in a 3.5 % NaCl solution, using SEM, AES and EDX. Changes in the surface chemistry were monitored after progressive exposures to the solution up to 42 hours. The coating was found to be thinner and more defective on the intermet...

The Cottrell-Stokes two-stage straining of fcc metals and intermetallic compounds whose yield stress exhibits an anomalous temperature dependence is analyzed theoretically. The magnitude of stress jumps brought about by changes in temperature is expressed via characteristics of dislocation transformations to shortand long-lived barriers. The manner in which the thermally activated blocking of d...

In the present study, friction spot welding or refill friction stir spot welding was performed to consolidate dissimilar AA5754 Al and AZ31 Mg alloys. The intermetallic compounds of Al12Mg17 and Al3Mg2 were primarily found in the weld, distributed at the interface between the base materials and in the Al top sheet. The distribution of the intermetallic compounds and the interfacial area between...

A nucleation-growth control for Al85Ni10Ce5 glass has transformed to a growth control for Al83Ni10Ce5Si2 glass. That’s to say a small quantity of Si addition can successfully separate the Al phase to single precipitate from a eutectic precipitation composited of Al and other intermetallic compound to synthesize nanostructured materials, characteristic of microstructures with finely dispersed na...