Impact and Sound Absorption of Porous Aluminum and Magnesium Alloy

1. MRS KOREA Materials Research Society of Korea Impact and Sound Absorption of Porous Aluminum and Magnesium Alloy Mechatronics Lab & i-cube center Joint Project School of Nano and Advanced Materials Engineering School of Mechanical Engineering

2. Agenda • Introduction • Experimental Method • Material for Experiment • Results - Sound Absorption • Equation for Damping ratio • Results – Vibration-Absorption • Conclusion

3. Introduction • A compound metal of foaming Magnesium is possible using a foaming agent. • Magnesium is lighter and stiffer than Aluminum. • Foaming aluminum-alloy has sound-absorption and vibration-absorption. • The comparison and analysis of quality is necessary between Al and Mg so that Mg has competitive. • This present time, Al is applied from the research which it sees consequently, in field of Mg more. It could be applied with the material which is excellent. • In order to evaluate a quality basic it used 2 branch methods and it measured the quality of material quality of the aluminum and Magnesium. • Tube Method • FFT Analyzer

4. Experimental Method Tube Method FFT Analyzer (Ono Sokki C5-5200) • The sound-absorbing characteristic test used Tube Method and it tested the aluminum and the Magnesium forming metal. It gave Air gap 10,30,50mm and it measured the sound-absorbing effect. • The test used the machine and the vibration measured how many diminish quickly using FFT Analyzer(Ono Sokki C5-5200). For the comparison of the metal and also the Ingot of the AM60 tested together.

5. a b c Fig.1. Photographs of Specimen for Impact and Sound Absorption Test. a) Aluminum Foam, b) AM60 Foam (Mg) , c) AM60 Ingot (Mg) Material for Experiment

6. Results - Sound Absorption Comparison of sound absorption coefficient with a) AM60 b) Pure Al • The recording low frequency sound-absorbing characteristic where the measurement result Air gap will be big became larger. • The highest point from each condition almost to be near 1. Sound-absorbing characteristic quite is superior.

7. Equation for Damping ratio Quality factor and bandwidth

8. Natural Frequency and Damping ratio Natural frequency (Hz) Damping ratio (ξ) Pure Al 3244 0.72 % AM60 2888 0.83 % AM60 Ingot 4922 0.63 % Results – Vibration-Absorption Damping ratio of Magnesium Forming metal was higher than Aluminum. (0.11%)

9. Modal Analysis which uses ANSYS

10. Conclusion • The objective of the test is to measure a quality and to compare blow. • Currently foaming Magnesium which are used wide industries and foaming aluminum research which are applied and actively advanced. • It evaluates a Magnesium application characteristic. • Sound-absorbing characteristic of Magnesium Forming metal quite is superior in the result of Sound Absorption. • Damping ratio of Magnesium Forming metal was higher than Aluminum in the result of Vibration-Absorption . • Consequently there is a necessity which will research quality, light weight and the quality of high-in-tensity of Magnesium Forming Metal. • In the future the more many research is necessary.

11. Q & A Thank you