The effect of particle properties on the morphological change of particles induced by impaction against a solid surface has been investigated using tristearin powders mixed with large and hard particles. It is found that the change in the bulk density of the heap formed on the solid surface can be successfully evaluated based on the effective impaction load introduced in our previous paper. At low impaction load, the heap constituted by tristearin powder having a larger Young＇s modulus shows a smaller bulk density. On the other hand, the bulk density of the heap at high impaction load is independent of the Young＇s modulus of tristearin powders. Furthermore, the degree of alpha-type crystal structure in the heap increases with increasing bulk density. These results suggest that high impaction load causes melting as well as deformation or crushing of tristearin particles.