• Journal of Powder Materials
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• v.1 no.1
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• pp.42-51
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• 1994

6061Al-SiCP metal matrix composite materials(MMCs) were fabricated by injecting SiCP particles directly into the atomized spray. The main attraction of this technique is the rapid fabrication of semi-finished, composite products in a combined atomization, particulate injection(10 $\mu\textrm{m}$, 40 $\mu\textrm{m}$, SiCP) and deposition operation. Conclusions obtained are as follows; The microstructure of the unreinforced spray formed 6061Al alloy consisted of relatively fine(50 $\mu\textrm{m}$) equiaxed grains. By comparision, the microstructure of the I/M materials was segregated and consisted of relatively coarse(150 $\mu\textrm{m}$) grains. The probability of clustering of SiCP particles in co-sprayed metal matrix composites increased it ceramic particle size(SiCP) was reduced and the volume fraction was held constant. Analysis of overspray powders collected from the spray atomization and deposition experiments indicated that morphology of powders were nearly spherical and degree of powders sphercity was deviated due to composite with SiCp particles. Interfacial bonding between matrix and ceramics was improved by heat treatment and addition of alloying elements(Mg). Maximum hardness values [Hv: 165 kg/mm2 for Al-10 $\mu\textrm{m}$ SiCp Hv--159 kg/mm2 for Al-40 $\mu\textrm{m}$SiCp] were obtained through the solution heat treatment at $530^{\circ}C$ for 2 hrs and aging at $178^{\circ}C$, and there by the resistance were improved.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.11a
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• pp.58-62
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• 2000

The fabrication process and analysis of thermal properties of 50~76vo1% SiCp/Al metal matrix composites(MMCs) for heatsink materials in electronic packaging were investigated. The 50~76vo1% SiCp/Al MMCs fabricated by pressure infiltration casting process showed that thermal conductivities were 85~170W/mK and coefficient of thermal expansion(CTE) were ranged 10~6ppm1k. Specially, the thermal conductivity and CTE of 71vo1%SiCp/Al MMCs were ranged 115~156W/mK and 6~7ppm/K. respectively, which showed a improved thermal properties than the conventional electronic packaging materials such as ceramics and metals.

• Tribology and Lubricants
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• v.25 no.1
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• pp.66-72
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• 2009

Al-based composites reinforced with SiC particulate were fabricated using a thermal spray process, and dry sliding wear behavior of the composites was investigated. Pre-mixed Al and SiC powders were sprayed on an A16061 substrate by flame spraying, and dry sliding wear test were performed under various sliding speed and applied load conditions against ${Al_2}{O_3}$ ball. Wear behavior of the composites was studied by using scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). And build-up mechanism of MML on the worn surface of the composites was examined. It was revealed that these MML was formed of debris from the contact surface of the composites and effected to wear behavior of the composites protecting the contact surface of the composites.

• Corrosion Science and Technology
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• v.11 no.4
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• pp.108-111
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• 2012

The effects of volume fraction (15-30%) of SiC particulate reinforcements on the corrosion behavior of SiCp/7091 Al composites in the 3.5% NaCl solution were studied by electrochemical techniques and scanning electron microscopy. The results showed that the amount of SiC particulate reinforcements did not cause much difference in the corrosion behavior of SiCp/7091 Al composites but the corrosion rate was proportional to the amount of SiCp reinforcement. And numerous pits and severe dissolution of the matrix was observed probably due to the discontinuities and galvanic effects between Al matrix and SiC reinforcements.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.29-33
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• 2001

In the present study, AZ91Mg/$\textrm{Al}_2\textrm{O}_3$ short fiber+SiC particulates hybrid metal matrix composites(MMCs) were fabricated by squeeze casting method. Different particulate sizes of 45, 29 and $9\mu\textrm{m}$ were hybridized with 5% volume fraction to investigate the effect of SiC particulates size on microstructure, mechanical and thermal properties such as hardness, flexural strength, wear resistance and thermal expansion. Results show that the microstructure of the hybrid composites were quite satisfactory, namely revealing relatively uniform distribution of reinforcements. Some aggregation of SiC particulates caused by particle pushing was observed especially in the hybrid composites containing in fine particulates($9\mu\textrm{m}$). The hardness and flexural strength were improved by decreasing particulates size, whereas wear resistance improved by increasing particulates size because of large particulates restricting matrix wear from contacted stress. Regardless of particulates size, thermal expansion of composites was the same. This may be because the content of particulates was in all cases 5 volume fraction.1

• Korean Journal of Materials Research
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• v.10 no.12
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• pp.793-798
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• 2000

The age-hardening behavior of unreinforced 6061 Al alloy and SiCp/6061 Al alloy composites reinforced with different size of SiC particle (average diameter ; 0.7$\mu\textrm{m}$ and 7.0$\mu\textrm{m}$) was investigated by hardness measurement, calorimetric technique and transmission electron microscopy. At 17$0^{\circ}C$ isothermal aging treatment, the peak aging time of 0.7$\mu\textrm{m}$SiCp/6061Al alloy composite and 7.0$\mu\textrm{m}$SiCp/6061Al alloy composite is shorter than that of unreinforced 6061Al alloy, and the aging of 7.0$\mu\textrm{m}$SiCp/6061Al alloy composite is accelerated more than that of 0.7$\mu\textrm{m}$SiCp/6061Al alloy composite. This acceleration is due to the increase of dislocation density by the compositeness with SiCp and the SiC particle size. In the peak aged condition, the major strengthening phase of these materials is intermediate $\beta$ phase(Mg$_2$Si), and the activation energy for the formation of $\beta$ phase is considerably decreased by the compositeness with SiCp and the increasing of SiC Particle site.

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05a
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• pp.146-147
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• 1992

• Journal of Korea Foundry Society
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• v.15 no.4
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• pp.360-367
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• 1995

Effects of metal coating treatment on SiC particle on wetting behavior and interfacial strength were studied. Experimental variables are included types of coated metallic films such as Cu and Ni-P, and temperatures of heat-treatment under vacuum. The experimental results concerning wetting phenomena of liquid Al on SiC, showed that coating treatment of metallic film on SiC particles remarkably improves the wetting behavior of liquid Al on SiC, especially in the case of Ni-P coating. The interfacial strength of Al/SiC composites made of coated SiC plate was higher than that of the composite with non-coated SiC plate although the coating treatment was not perfect.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1998.04b
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• pp.29-29
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• 1998

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05b
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• pp.21-22
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• 1992