Effect of (La+Yb) addition on the fluidity of an A356.2 aluminum alloy

ABSTRACT

The effect of mixed rare earth (La+ Yb) addition on the fluidity of A356.2 was investigated by fluidity tests, optical microscope (OM), environmental scanning electron microscope (ESEM) with energy diffraction spectrum (EDS) and X-ray diffraction (XRD). Varying amounts of (La+ Yb) addition were tested, 0%，0.3%，0.6%, and 0.9% (wt.%). The fluidity of A356.2 was improved with the addition of mixed rare earth (La+ Yb). The fluidity length of the A356.2 + 0.6% (La+ Yb) alloy (670mm) was increased by 19% compared to that of A356.2 (565mm). The fluidity of the alloy was related to the morphology of α-Al and Al₈Si₆Mg₃Fe（Fe phase）in the alloy. A refined microstructure of the alloy corresponded with better fluidity. A higher pouring temperature also improved fluidity. However, this trend declined when the pouring temperature increased above 730°C.

KEYWORDS:

• Mixed rare earth
• aluminum alloy
• microstructure
• fluidity
• grain refinement
• Fe phase

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The project is supported by the National Natural Science Foundation of China (51364035), the Natural Science Foundation of Jiangxi Province (No. 20171BAB206034), Loading Program of science and Technology of College of Jiangxi Province (KJLD14003) and Research Project of Jiangxi Provincial Department of Education (GJJ170453).