Microstructural Development and Mechanical Behaviour of SiC Whisker-Reinforced Mg-Li Alloys
Preform production, squeeze infiltration and extrusion procedures are described for the preparation of single phase (β) Mg-Li alloys reinforced with SiC whiskers. Observations are reported on the generation of whisker alignment and second phase distribution as a result of preform binder dissolution and re-precipitation.Tensile test data are given, showing that the presence of whiskers can lead to considerable property enhancement. Dynamic stress relaxation processes appear to affect the tensile behaviour at room temperature over the range of strain rates employed during conventional testing. It is thought that this is associated with the very fast diffusion kinetics exhibited by the lithium.
KeywordsMetal Matrix Composite Critical Strain Rate Lithium Loss Whisker Surface Dark Field Transmission Electron
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