Influence of impurities on the resistance to spall fracture of aluminum near the melting temperature

This paper presents the results of comparative experiments with commercial aluminum AD1 and aluminum A999 of high purity which were designated for measurements of spall strength of these materials at room temperature and at $$640\,^{\circ }\hbox {C}$$ . The measurements confirmed a sharp drop of the spall strength of commercial aluminum when approaching the melting temperature, which probably is associated with an earlier beginning of melting on the grain boundaries with higher concentration of impurities. The pure aluminum A999 maintains high spall strength near the melting temperature.