The distribution of boron in aluminium, the grain of which had been refined by the addition of the alloy AlTi5B1, was investigated by means of neutron-induced autoradiography and quantitative image analysis. Some aspects and problems of metallegraphic methods for the determination of boron particles in aluminium are discussed. Besides the practice classification on the detector by image analysis the results thus obtained were converted into structure parameters by rising model assumptions and by measurements. In addition, particle density and average particle distance were determined. Experimental results confirm the possibility of using the method described to study grain-refining processes initialed by boron-containing master alloys.