The effect of eutectic structure and long period stacking ordered (LPSO) structure on the corrosion resistance of Mg 95.5 Gd 3.5 Zn 1 alloy has been investigated. The eutectic structure and LPSO phase were obtained by different heat treatments and their corrosion behavior and microstructures were examined by immersion test, electrochemical measurement, and SEM. It is suggested that the Mg 95.5 Gd 3.5 Zn 1 alloy containing LPSO phase has a better corrosion resistance than that without LPSO phase. This is due to the smaller accelerating corrosion effect, which is caused by the contact between a-Mg and LPSO phase. Figure 4. Cross-sectional SEM images of corroded surface after immersed in 0.17 M NaCl solution for 18 h: (a) aged Mg 95.5 Gd 3.5 Zn 1 alloy with LPSO phase and (b) as-cast Mg 95.5 Gd 3.5 Zn 1 alloy with eutectic structureFigure 5. Polarization curves of the as-cast and aged Mg 95.5 Gd 3.5 Zn 1 alloys in 0.17 M NaCl solution at room temperature www.matcorr.com

Hardness is an essential mechanical indication of cemented carbides. The current work presents an approach to predict the hardness of three-phase WC-Co-Cubic cemented carbides, which establishes a relationship among composition, structure and mechanical performance. With the input of initial composition and grain sizes of carbides, structural parameters needed to predict the hardness can be calculated by thermodynamic calculations and diffusion simulations. The calculated hardness of a series of WC-Co-Cubic cemented carbides agree reasonably with experimental data. The present model is of reference to predict the hardness for multi-phase composites and design the new type of WC-Co-based cemented carbides.