What are the disadvantages of adding calcium to az91?
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The disadvantages of adding calcium to AZ91 magnesium alloy include potential issues related to the phase composition, solidus temperature, and alloy oxidability. While calcium can form intermetallic compounds like Al2Ca, which may enhance oxidation resistance and reduce the ignition temperature, it is crucial to prevent contamination during the alloying process to maintain satisfactory mechanical properties. Additionally, the use of calcium in place of rare earth (RE) elements as a grain refiner may slightly lower the mechanical strength properties of the alloy. However, the cost-saving and energy-saving benefits of using calcium over RE elements in large-scale industrial production, especially for high-energy consumption vehicles, make it a more suitable option despite these minor drawbacks.
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| Papers (4) | Insight |
|---|---|
2 Citations | Adding calcium to AZ91 can lead to the formation of intermetallic compounds like Al2Ca, which can reduce β-Mg17Al12 and refine the microstructure, suggesting no specific disadvantages mentioned in the paper. |
2 Citations | Adding calcium to AZ91 can lead to contamination, affecting mechanical properties. However, it increases ignition temperature, reduces oxidability at high temperatures, and requires careful production processes to prevent issues. |
13 Citations | Adding calcium to AZ91 alloy can lead to slightly lower mechanical strength properties compared to using RE elements, but it offers significant cost and energy savings, making it more suitable for industrial production. |
| Not addressed in the paper. |
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