Nucleation Effect of Ti-6Al-4V Powder on Al-Si Eutectic Alloy

作者：Sarajan Zohair^*

来源：Materials and Manufacturing Processes, 2009, 24(12): 1354-1358.

DOI：10.1080/10426910902997167

• Casting process
• Damping effects
• Elongation
• Eutectic Al-Si
• Globular form
• Grain size
• Hydrogen degassing
• Inoculants
• Melt homogenized
• Metal powder
• Needle-plate-like
• Nucleation
• Silicon secondary phase
• Tensile strength
• TiAl3 phase
• Ti-6Al-4V chips

In this research nucleation effect of Ti-6Al-4V powder on grain size and tensile strength of Al-12.1% Si eutectic alloy was studied. Metal powder produced from Ti-6Al-4V machining chips by meshes of 50 and 140 and weight percentages of 0.1, 0.15, 0.2, and 0.25 were used. The microstructure by mesh 50 with 0.15wt% consists of grain with average size of 6 mu m, tensile strength and elongation equal to 492MPa and 7.25%, respectively. By mesh 140 with 0.15wt% the considered values are equal to 10 mu m, 540MPa, and 8.82%, respectively. Before refinement the needle-plate-like eutectic silicon is distributed arbitrarily. The morphology of the eutectic silicon is changed from needle-plate to a fibrous form with addition of 0.15wt% of mesh 50 and finally changes its morphology from a needle-plate to a globular form after adding 0.15wt% of mesh 140, which is fully modified. SEM/EDX micro-analyzing shows that TiAl3 compound has been formed, which is the major factor in grain size modification and tensile strength increasing. This phase is formed prior to solidification of Al-Si alloy makes it an efficient nucleation site for aluminum grains upon solidification.

• 出版日期2009