Corrosion and wear resistance of hypo eutectic Zn eAl alloys as a func tion of structural features

A .E. ARES; L.M. GASSA; C.E. SCHVEZOV; M.R. ROSENBERGER

MATERIALS CHEMISTRY AND PHYSICS

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2012 p. 1 - 21

0254-0584

The aim of the present research was to investigate the role of the type of grain ma crostructure (colum nar, colum nar-to-equiaxed transition e CET -, an d equiaxed) and microstructure ( secondary dendrite arm spaci ng - l 2 ) in the wear and el ectrochemical behavior of hype reutectic Zn e Al all oys (Zn- 1wt%A l, Zn- 2wt %Al, Zn-3wt% Al and Zn- 4wt%A l) directionally solidi fi ed in a vertical upward directional solidi fi ca tion dev ice. We also aime d to, correlate the thermal parameter s with the electrochemical and wear prop-ertie s. The results obtai ned in this all oy system indicate that the corrosion resistance decreases as the conc entration of aluminum increases, but tha t at the highes t conc entrations ( near the eutectic conc entration) t his resistance de pends on the str ucture. For the same wear cond itions, the wear rate of the equiaxed region is lower t han the colum nar and transition regions. Independe ntly of the type of struc ture, wear resistance increases as the aluminu m conc entration in creases. For each all oy concen tration, the wear resistance increases from the columna r to the equiaxed struc ture. A clear inverse relation is obs erved be tween the wear resistance and l 2 , whic h may explain the increase in wear resistance in the equiaxed region. At low spacings, the wear rate converges to a single value