Al-Ce alloys provide economical silicon-free Al-casting solutions

CMI researchers at University of Tennessee Knoxville with industry partners Eck Industries, Shiloh and Borg Warner conducted the research for this highlight

line graph shows silicon metal price has seen a sharp increase in the last few months due to shortages and high demand
Silicon metal price has seen a sharp increase in the last few months due to shortages and high demand

Innovation 
Ce has been shown to be an effective alternative to Si in aluminum casting alloys across all foundry manufacturing.

Achievement
CMI has developed Si-free casting alloys with superior castability and mechanical properties vs Al-Si alloys.

Significance and Impact

  • Silicon is used as a primary alloying element in aluminum as well as in computer chips, transistors, and solar cells.
  • Silicon prices have spiked over 400% in the last year, making Al-Ce alloys far less expensive (see figures).
  • Demand for Si will only increase: automotive wheels contain 6% Si, and the largest volume die-casting alloy is 9% Si.

Hub Target Addressed 
Diversifying the supply of REE by increasing the value of co-mined cerium. Conversion of critical materials into high-value end products. Industry adoption of REE technology.

bar graph shows the cost of silicon in aluminum alloys follow the same trend due to its use as a primary alloying element in 4%–20% by weight.
The cost of silicon in aluminum alloys follow the same trend due to its use as a primary alloying element in 4%–20% by weight.