Correlation between Thermal Parameters, Primary Dendrite Arm Spacing and Microhardness on a Directionally Solidified Ternary Al-6wt%Cu-8wt%Si Alloy
The objective of this paper is to present an experimental study that aimed to establish correlations between primary dendrite spacing (λ1) and microhardness of a ternary Al-6wt%Cu-8wt%Si alloy solidified under transient heat extraction, using a horizontal unidirectional water-cooled solidification device. To examine the microstructural evolution, solidification thermal parameters (growth rate and cooling rate - VL and TR, respectively) were calculated through the application of an experimental method and were then correlated with λ1 using analytical power functions laws. The correlation between microstructural parameters and the measured microhardness values are presented in the forms of power and Hall-Petch types of equations. The analysis of the microstructure of the investigated alloy indicated that the increasing of TR and VL reduced the primary dendrite arm spacing, increasing the microhardness.
Andreas Öchsner, Graeme E. Murch, Ali Shokuhfar and João M.P.Q. Delgado
O.L. Rocha et al., "Correlation between Thermal Parameters, Primary Dendrite Arm Spacing and Microhardness on a Directionally Solidified Ternary Al-6wt%Cu-8wt%Si Alloy", Defect and Diffusion Forum, Vol. 365, pp. 136-141, 2015