Growth of AlN by Reactive Gas Injection of Nitrogen in an AlMg Matrix

The primary objective of the present research was to provide a fundamental understanding of the processing science necessary to fabricate the Aluminum Nitride (AIN) reinforced Aluminum-Magnesium (AIMg) composites via Reactive Gas (N2) Injection in the AIMg alloy melt. Aluminum nitride (AlN) matrix composites were prepared by a novel approach. It was possible to produce a considerable amount of AIN particles in the AI alloy matrix at a reaction temperature as low as 900 °C utilizing the in-situ nitration reaction process developed in the present study. The volume fraction of AIN increases almost linearly with increasing the magnesium (Mg) content in the alloy and the reaction time. The shapes of AIN particles were found to have different forms, whose sizes were in the range from submicron to a few microns. From the present study, it is concluded that the new innovative in-situ nitridation process developed in the present study can be successfully applied for processing of high strength AIMg/AIN composites. For particles and composite structure characterization some methods were used, including: scanning microscopy, quantitative analysis of selected composite regions and XRD analyses. Composite structure and reinforcement distribution was compared with use of quantitative analysis. Morphology and diffraction pattern of aluminum nitride particles was shown. Typical structure of studied composites with microanalysis results was indicated. Aluminum nitride dispersion change was represented.