ISSN:
1662-9779
Quelle:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Thema:
Physik
Notizen:
Extrusion directly following vacuum infiltration is a special forming technique thatcombines the advantages of liquid metal infiltration and semisolid extrusion. The major advantages ofthis process are elimination of porosity and shrinkage, good surface finish, good dimensionalaccuracy, high strength to weight ratio and near net shaping. Magnesium matrix composites arefabricated usually through stirring casting, powder forming, injecting deposition, liquid metalinfiltration or die casting at present time. However few investigations on magnesium matrixcomposite are conducted for the specific characteristics of magnesium alloy, such as high chemicalactivity and easy oxidation. The present paper is focused on Csf/Mg composites obtained viainfiltration of porous short carbon fiber preform by liquid Magnesium. The complete experimentsetup is designed and fabricated by ourselves, which include the forming molds, the unit for meltingthe magnesium, the unit for vacuuming and the monitoring and collecting system of forming processparameters. In this method the whole experiment setup is vacuumed firstly. Then the pressurizednitrogen is used to infiltrate the magnesium melt through a porous preform of short carbon fibers.After the infiltration completed, the punch of the press extrude the magnesium-infiltrated preform outof the forming die to form the tubes or bars. X-ray diffraction (XRD), optical and SEM microscopeswere used to characterize the infiltration and the microstructure of fabricated composites. Thecompression test was used to characterize the mechanical properties of fabricated composites. Theresults show that the preform was infiltrated thoroughly by melt magnesium and the fabricated Csf/Mgcomposites have excellent mechanical properties compared with the magnesium alloys. Csf/Mgcomposites should be very promising candidates for automobile parts and portable electronicappliance parts in the future
Materialart:
Digitale Medien
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/24/transtech_doi~10.4028%252Fwww.scientific.net%252FSSP.141-143.91.pdf
