Squeeze Casting of SiC Whisker Reinforced Magnesium Composites

용탕단조를 이용한 SiC 휘스카 강화 마그네슘복합재료의 제조

Squeeze casting was performed to fabricate the SiC whisker reinforced magnesium matrix composites, and the suitability of the squeeze casting for the production of the sound composites was determined by micro/macro-structures observations and tensile test. The two-directional infiltration of the melt and the removal of air during infiltration using the devised mold were necessary to produce the composites. The pressure of 100 MPa was effective for the production of composites with the SiC whisker volume fraction of 30%, but the pressure should be lower than 50 MPa in case of below 20% in the volume fraction. The SiC whiskers in the squeeze cast composites were randomly and densely aligned, and the SiC whiskers/magnesium interfaces were continuously well-bonded. The elastic modulus, 0.2% proof stress and tensile strength in the composite were about 2.5times, l0times and 4times as large as those of magnesium, respectively, indicating that the squeeze casting sufficiently provides the high strength magnesium composites reinforced with SiC whiskers.