Effect of Cooling Rate on the Microstructure and Mechanical Properties of ZK60 Alloy


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Microstructure and mechanical properties of Mg-6.0wt%Zn-0.5wt%Zr (ZK60) alloy were studied as a function of cooling rate. The temperature field and cooling rate during the casting process were investigated by use of finite element analysis (FEA) simulation. The results showed that the microstructure was refined and the eutectic phase distributed much uniformly with the increase of cooling rate. The increase of yield strength, ultimate strength and elongation can be ascribed to the strengthening effect of fine grain. Relationship between grain size and yield strength is consistent with the Hall-Petch formalism: 1/ 2 80.37 132.56 − = + d y σ .



Materials Science Forum (Volumes 546-549)

Edited by:

Yafang Han et al.




J. B. Lin et al., "Effect of Cooling Rate on the Microstructure and Mechanical Properties of ZK60 Alloy", Materials Science Forum, Vols. 546-549, pp. 319-322, 2007

Online since:

May 2007




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[10] [20] [30] [40] [50] [60] [90] 120 150 180 210 240 270 Yield Strength Tensile Strength Elongation Elongation, % Strength, MPa (V)(IV) (II) (III) (I) Fig. 7 Tensile properties of the center of each step 0. 08 0. 10 0. 12 0. 14 0. 16 0. 18.

[90] [93] [96] [99] 102 105 R=0. 99699 Yield Strength, MPa d-1/2 (µm-1/2) σσσσy=80. 37+132. 56d-1/2 Fig. 8 Grain size dependence of yield strength of ZK60 step-like casting.