Correlation between unsteady-state solidification microstructure and wear behavior

Abstract

In the past, many studies have been performed on the improvement of mechanical properties of alloys by refining grain size. Nonetheless, there is considerable uncertainty regarding the mechanism of the grain size effect. In this talk, it will be shown that the influence of microstructural features, located inside the grain, such as the matrix morphology (cell, dendrite) and second-phase particles, can be particularly important from the point of view of mechanical behavior. The influence can often be quantified in a constitutive relation that is an appropriate variant on the familiar Hall-Petch relation: the quantitative improvement in properties varies with d-1/2 , where d is the microstructural feature spacing. Since microstructural features can be tailored by processing the molten metal, it is important to understand how they evolve during solidification, being controlled by cooling and solidification rates. This talk aims to present some of the results from the work developed during his stage at CENIM, referring to the correlation between unsteady-state solidification microstructure of Zn-Al-Bi alloys and wear behavior.