China Foundry (Mar 2015)
Grain refinement limit of commercial pure Al inoculated by Al-Ti-C (B) master alloys
Abstract
The grain refinement limits of commercial pure Al inoculated by Al-5Ti-1B, Al-5Ti-0.25C and Al-5Ti-0.3C-0.2B master alloys were studied, and the influence of melting temperature on the grain refining performance of these three master alloys was investigated using a high scope video microscope (HSVM), a field-emission scanning electron microscope (FESEM), an electron probe micro-analyzer (EPMA) and X杛ay diffraction (XRD) method. Results show that there is a grain refinement limit of commercial pure Al refined by these three master alloys; with the same addition level of 1.5% under the present experimental conditions, the grain refinement limits (smallest average grain size) of commercial pure Al refined by Al-5Ti-1B, Al-5Ti-0.25C and Al-5Ti-0.3C-0.2B master alloys are 50 祄, 80 祄 and 80 祄, respectively. In addition, with an increase in the melting temperature of the pure Al, the grain refining performance of Al-5Ti-1B and Al-5Ti-0.25C master alloys decreases, but the grain refining performance of Al-5Ti-0.3C-0.2B changes little.
