Rott N. The effect of vibrational impact of low power density on the structure and properties of eutectic materials

The paper develops scientific bases of the impact of castings vibromechanical treatment during the solidification of a melt on formation laws of structure and fine structure depending on vibration frequency as well as mechanical properties of the materials with eutectic components. The paper demonstrates the effect of vibrational impact of law power density of sound range frequencies (0 … 800 Hz) on mechanical and performance properties of the aluminium alloys Al-Si and Al-Cu, and Hadfield steel (110H13L) by means of superfine structure formation. It is found that mechanical vibration with ~ 50 Hz frequency can change as much as possible structural constituents ratio in such alloys and enable to improve hardness indices. It is demonstrate that during steel 110H13L solidification under the impact of mechanical vibrations of low power density of 50 Hz frequency there is the formation of equiaxed austenitic structure with a uniform distribution of alloying element along grain cross section; on grain boundaries there is ternary eutectic with comparatively thick equidistant plates of carbides (Mn, Fe)3C with the spaces filled in the second component - superfine eutectic (Mn, Fe) + (Mn, Fe)3P. Such ternary eutectic morphology improves strength and plasticity properties of castings as well as reduces negative impact of phosphide eutectic on probable brittle fracture of steel.