مشخصه یابی ریزساختاری آلیاژ Al-8Fe-1.4V-8Si تحت ریخته گری

Microstructural characterization of squeeze-cast Al–8Fe–1.4V–8Si

مشخصه یابی ریزساختاری آلیاژ  Al-8Fe-1.4V-8Si تحت فرایند ریخته گری فشاری

 

ABSTRACT

This paper investigates the effect of vanadium on the composition and morphology of intermetallics formed during the squeeze casting of Mgmodified Al–8Fe–1.4V–8Si alloy in both monolithic form and as-reinforced with 7.58, 10.52 and 15.68 wt.% SiC particles (SiCp). Iron intermetallics of -Al7(Fe,V)3Si and -Al18Fe11Si phases were predominantly observed in the alloy and composite. SEM studies and the EDX analyses revealed that refinement of Fe-intermetallics and modification of -phases to less deleterious morphologies of -phases has been achieved by vanadium addition of 1.4%. Also, heat treatment enhances V diffusion and SiC particles act as nucleation sites for the formation of finer -intermetallics. Fractographs exhibited cracking of long -phases and partial decohesion of SiCp from the matrix.

مطالعه امکان­پذیری فرآیند ریخته­ گری تحت­ فشار در خلأ

A feasibility study of the partial squeeze and vacuum die casting process

مطالعه امکان­پذیری فرآیند ریخته­ گری تحت­ فشار در خلأ و انقباض جزئی

ABSTRACT

A feasibility study of the partial squeeze and vacuum die casting process was performed to make defect-free casting products with excellent mechanical properties. The trial die casting process in this study was industrially implemented for producing a reaction shaft support made of a hyper eutectic Al±15%Si alloy. To combine the squeezing and vacuum effect, the plunger injection system was designed and attached to a chill vent type vacuum machinery system. The combination of the vacuum effect before injection and the squeezing effect after injection resulted in excellent defect-free die casting products. The uniform distribution of ®ne acicular eutectic and proeutectic silicon obtained from the trial process also provided excellent mechanical properties.