Magnesium based composite material and method for making the same

• US 8,734,602 B2
• Filed: 12/26/2010
• Issued: 05/27/2014
• Est. Priority Date: 06/14/2010
• Status: Active Grant

• Current Assignee: Hon Hai Precision Industry Co., Ltd., Tsinghua University
• Original Assignee: Hon Hai Precision Industry Co., Ltd., Tsinghua University
• Inventors: Li, Wen-Zhen, Chen, Hwang-Miaw
• Primary Examiner(s): Roe, Jessee
• Assistant Examiner(s): KESSLER, CHRISTOPHER S
• Application Number:
  US12/978,621
• Publication Number:
  US 20110303866A1
• Time in Patent Office: 1,248 Days
• Field of Search: 752/30, 148/557
• US Class Current: 148/557
• CPC Class Codes: B22D 1/00 Treatment of fused masses in the ladle or the supply runners before casting for continuous casting B22D11/10; metallurgical processing, e.g. refining of iron or other metal C21, C22, C25C
• CPC Class Codes: B22D 27/08 Shaking, vibrating, or turning of moulds
• CPC Class Codes: B22D 27/20 Measures not previously mentioned for influencing the grain structure or texture; Selection of compositions therefor
• CPC Class Codes: C22C 1/1036 starting from a melt

Abstract

The present disclosure relates to a magnesium based composite material. The magnesium based composite material includes a magnesium based metal matrix and nanoparticles dispersed in the magnesium based metal matrix in a weight percentage of a range from about 0.01% to about 2%. The present disclosure also relates to a method for making the magnesium based composite material. In the method, the nanoparticles are added to the magnesium based metal at a temperature of about 460° C. to about 580° C. to form a mixture. The mixture is ultrasonically vibrated at a temperature of about 620° C. to about 650° C. The mixture is casted at a temperature of about 650° C. to about 680° C., to form an ingot.

Claims

1. A method for making the magnesium based composite material, the method comprising the following steps:

providing magnesium based metal and nanoparticles;

adding the nanoparticles to the magnesium based metal at a temperature of about 460°

C. to about 580°

C. to form a mixture while mechanically stirring the magnesium based metal, to achieve a preliminary mix between the magnesium based metal and the nanoparticles;

ultrasonically vibrating the mixture at a temperature of about 620°

C. to about 650°

C., to uniformly disperse the nanoparticles in the magnesium based metal; and

casting the mixture at an increased temperature of about 650°

C. to about 680°

C., to form an ingot.

2. The method of claim 1, wherein the steps are processed in a protective gas.

3. The method of claim 1, wherein the ultrasonically vibrating is at a vibration frequency of about 15 kHz to about 20 kHz.

4. The method of claim 1, wherein the ultrasonically vibration lasts for about 5 minutes to about 40 minutes.

5. The method of claim 1, wherein the nanoparticles are selected from the group consisting of carbon nanotubes, silicon carbon nanograins, alumina nanograins, titanium carbon nanograins, boron carbide nanograins, graphite nanograins, and combinations thereof.

6. The method of claim 1, wherein a weight percentage of the nanoparticles is in a range from about 0.01% to about 10%.

7. The method of claim 1, wherein a weight percentage of the nanoparticles is in a range from about 0.5% to about 2%.

8. The method of claim 1, wherein a size of the nanoparticles is in a range from about 30 nanometers to about 50 nanometers.

9. The method of claim 1, wherein a material of the magnesium based metal is AZ91 magnesium alloy, AM60 magnesium alloy, AS41 magnesium alloy, AS21 magnesium alloy, or AE42 magnesium alloy.

10. The method of claim 1, wherein a material of the magnesium based metal is AZ91D magnesium alloy and the nanoparticles are carbon nanotubes, and a weight percentage of the nanoparticles is about 1.5%.

11. The method of claim 1, wherein a crystalline grain size of the ingot is in a range from about 100 microns to about 150 microns.

12. The method of claim 1 further comprising an extrusion step of the ingot to reallocating the nanoparticles in the ingot.

13. The method of claim 1 further comprising a step of forming an enclosure of an acoustic device from the ingot.

14. The method of claim 13, wherein the acoustic device is an earphone.

15. The method of claim 13, wherein the acoustic device has a total harmonic distortion smaller than a comparing acoustic device using a comparing enclosure consisting of magnesium based metal and having a same size and shape with the enclosure of the acoustic device.

16. The method of claim 15, wherein the total harmonic distortion of the acoustic device is at least 10% less than the total harmonic distortion of the comparing acoustic device.