The Impact of AL-TI-B Grain-Refiners from Different Manufacturers on Wrought AL-alloy

To investigate the impact of various Al-Ti-B grain-refiners on solidification and grain-refining performance, a wrought aluminium alloy AA6182 was used.Three different grain-refiners from different manufacturers were used to establish the efficiency, i.e. contact time before casting, on the primary solidification and grain formation size.The primary solidification of α-Al grains at inoculation was observed by using thermal analysis (TA).Differential scanning calorimetry (DSC) was used in order to analyze the quality of various grain-refiners.The size of the primary grains was analyzed using optical microscopy (OM).Scanning electron microscopy (SEM) was used to estimate the size and distribution of Al 3 Ti and TiB 2 particles in various grain-refiners and to establish the best efficiency of the investigated grain-refiners.Within 1-4 min of inoculation the smallest fine equiaxed grains were achieved when either one of the investigated grain-refiners was added.It was established, that grain-refiner A contains higher content of impurities which do not melt in the experimental temperature range made by DSC method.The most pure grain-refiner turned out to be grain-refiner B, in which the most optimal number of TiB 2 particles and particle size distribution was found.