Zn, and Si, which are all soluble in aluminium. For every chemical composition of these alloys it is thus essential to A commercially available PM Al-5•5Zn-2•5Mg-1•6Cu point out that liquid phase sintering promotes the basic (wt-%) alloy has been used to study the eVect of mechanisms for neck formation, the development of the elemental Mg additions, ranging from 0 to 4•5 wt-%, alloys and constitution of their microstructure. Speci c on its sinterability and mechanical properties after chemical compositions are designed to obtain heat treatable sintering and heat treatment of the W and T6 type.alloys with enhanced mechanical strength. DSC experiments were performed to study the chemical A great deal of research has been conducted to study reactions occurring during sintering. Results obtained the sinterability of binary 1 7 ,1 8 , 2 1 -2 4 and more complex 1 9 , 2 4 -2 9 from dilatometry and DSC experiments were used to Al alloys. These works report on the in uence of sintering aid determination of the optimum sintering cycles parameters, such as atmosphere, temperature, heating rate, under nitrogen. DSC experiments performed on as particle size, and type of the metallic additions, amongst sintered samples were used for the determination of the others, on the mechanical properties and the dimensional solution treatment temperature. The microstructure stability of the compacts. Liquids in these systems may form obtained after sintering of the experimental Al alloys by melting of the additives themselves or through a eutectic was characterised by SEM and XRD. The mechanical reaction between Al and the added metallic powders. properties of the alloys, both, in the as sintered andAlthough there is a certain degree of controversy on the heat treated states were obtained from tensile testing way to introduce the alloying elements, the use of prealloyed and hardness measurements. Additional theoretical powders represents an obvious alternative and more research calculations, using the THERMOCALC programme, is needed in this area. At present, its utilisation has been along with the experimental observations, were carried pointed out as unattractive because of diYculties during out as an alloy design method to suggest an alternative compaction 1 9 in spite of apparent advantages related to chemical composition and alloying strategy aimed at the dimensional stability of the compacts. 1 8 upgrading the sintering behaviour and mechanicalOther authors, mainly working on binary alloys, 1 6 ,1 7 ,2 0 , 2 4 ,3 0 properties of the present alloy.PM/0987 have also carried out metallographic analyses on specimens subjected to diVerent sintering conditions, while fewer works The authors (
