Microstructure and mechanical properties of graphene nanoplates reinforced pure Al matrix composites prepared by pressure infiltration method

Abstract In situ TiB2/Al-4.5Cu composites with different TiB2 particle amounts were fabricated by the salt-metal reaction technique. The effects of in situ TiB2 on the microstructure and mechanical properties of Al-4.5Cu alloy were studied in this paper. The results showed that in situ TiB2 particles had significant effect on refining grain size and improving mechanical properties of as-cast Al-4.5Cu alloy. With the amounts of TiB2 particles increasing, the yield strength and ultimate tensile strength were improved, while the elongation reduced. The strengthening mechanisms of the in situ particle-reinforcing Al matrix composites were discussed, and the yield strength was predicted accurately by accounting for the three strengthening mechanisms and particle distribution.

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Microstructure and compressive behavior of lamellar Al2O3p/Al composite prepared by freeze-drying and mechanical-pressure infiltration method

Science and Engineering of Composite Materials ◽

10.1515/secm-2020-0001 ◽

2020 ◽

Vol 27 (1) ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Qiang Zhang ◽

Shanliang Dong ◽

Shuai Ma ◽

Xuwei Hou ◽

Wenshu Yang ◽

...

Keyword(s):

Freeze Drying ◽

Perpendicular Direction ◽

Matrix Composites ◽

Mechanical Pressure ◽

Pressure Infiltration ◽

Ceramic Scaffold ◽

Al Composite ◽

Al Matrix Composites ◽

Infiltration Method ◽

Al Matrix

AbstractInfiltrated molten Al matrix by mechanical-pressure infiltration method into the ceramic scaffold prepared by freeze-drying technology could prepare dense lamellar Al matrix composites without damage of the biomimetic microstructure of the scaffold. However, the investigation of lamellar Al matrix composites prepared by freeze-drying and mechanical-pressure infiltration method has not been fully understood yet. In the present work, the Al2O3 scaffold with pearl layer structure was prepared by freezing-dry method, and eventually the lamellar Al2O3p/Al composite was fabricated by mechanical-pressure infiltration method. The Al matrix was infiltrated well into the large pores of the Al2O3 scaffold, and the lamellar structure of the Al2O3 was well preserved. The hardness of the lamellar Al2O3p/Al composite was isotropic in transvers and perpendicular directions. However, the compressive strengths of the lamellar Al2O3p/Al composite were significant anisotropic while the compressive strength in transvers direction was 127.7% higher than that in the perpendicular direction, indicating the integrality of the lamellae microstructure (especially the bridging layers). Due to the mismatched deformability, weak debonding was observed between Al and Al2O3p/Al layers in the fracture surface of the lamellar Al2O3p/Al composite. It indicates that the interfacial bonding between Al and Al2O3p/Al layers is rather strong, which is beneficial for higher strength in transvers direction but lead to lower strength in perpendicular direction.

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