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The effects of minor Al and Ce on the microstructures, room-temperature and high-temperature mechanical properties of as-cast Mg-6Zn magnesium alloys were investigated. With the Al addition into Mg-6Zn alloy, the coarse eutectic Mg51Zn20phases were refined and distributed discontinuously. After adding 0.5wt.% Ce into Mg-6Zn-1Al alloy, a new needle-like Al2CeZn2phase was observed. Meanwhile, the volume fraction of Mg51Zn20phase decreased and the semi-continuous Mg51Zn20phase became discontinuous globular morphology. It has been observed that the addition of Ce element coarsens the grains, and 1wt.% Al addition enhanced the yield strength and ultimate strength from 86.35MPa, 229MPa to 90.7MPa, 238MPa, respectively. Moreover, the Ce addition can significantly increase the high-temperature mechanical properties of cast Mg-6Zn-1Al alloy.

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In view of the increasing consumption of fossil energy, heavy oil with large reserves and wide distribution, as an important unconventional oil and gas resource, has attracted more and more attention in its exploration and development. However, due to the high content of heavy components in heavy oil, its viscosity is high, its fluidity is low, and its quality is poor. Therefore, the key to enhance heavy oil recovery is to reduce its viscosity, improve its fluidity and