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This study presents a panorama of the AlSi7Mg0.6 (A357) aluminum alloy in additive manufacturing by selective laser melting. The document is mainly interested in the metallurgical tempers obtained after manufacture and after heat treatment; it quickly cover the process. The results concerning the material integrity (porosity), mechanical properties, microstructures, residual stresses, etc., are presented in order to best define the technological capacities of these metallurgical tempers: as-built, soft annealed, T6, and artificial aging. Some information on the mechanisms and kinetics of precipitation is also presented using the Johnson-Mehl-Avrami-Kolmogorov model. Finally, the conclusion proposes an inventory (advantages/disadvantages) of the metallurgical tempers obtained to better understand the industrial applications.

The thermal transport properties of five predominately pearlitic grades of grey, compacted graphite and spheroidal graphite iron have been investigated by the laser flash technique. Samples have been taken from cylinders cast in controlled thermal environments designed to produce three dissimilar cooling rates. Digital image analysis has been utilised in order to characterise the different graphite morphologies. The results indicated linear relationships between the thermal transport properties and the roundness of the graphite and the nodularity for compacted graphite and spheroidal graphite iron. A pronounced decrease in the thermal conductivity occurred when the lamellar graphite structure was transformed into compacted graphite. The thermal conductivity of compacted and spheroidal graphite iron has been recalculated with good accuracy over a temperature range of 25-500uC by means of regression analysis.

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