Effects of whisker surface modification on microstructures, mechanical and thermal properties of β-Si3N4 whiskers reinforced Al matrix composites

Diamond-particle-dispersed aluminum (Al) matrix composites consisting of monomodal and bimodal diamond particles were fabricated in spark plasma sintering process, where the mixture of diamond, pure Al and Al-5mass% Si alloy powders were consolidated in liquid and solid co-existent state. Microstructures and thermal properties of the composites fabricated in such a unique way were investigated and the bimodal and monomodal diamond particle effect was evaluated on the thermal properties of the composites. The composites can be well consolidated in a temperature range between 773 K and 878 K and scanning electron microscopy detects no reaction product at the interface between the diamond particle and the Al matrix. Relative packing density of the composite containing monomodal diamond particles decreased from 99.1% to 87.4% with increasing volume fraction of diamond between 50% and 60%, whereas that of the composite containing bimodal diamond particles was higher than 99% in a volume fraction of diamond up to 65%. The thermal conductivity of the composite containing bimodal diamond particles was higher than that of the composite containing monomodal diamond particles in a volume fraction of diamond higher than 60% and the thermal conductivity of the composite containing 70 vol.% bimodal diamond particles was 578 W/mK at R.T..

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Microstructural characteristics and mechanical behavior of microwave-assisted sintered ferromagnetic FeCoNi1.5CrCu HEAp/Al matrix composites

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2020.158439 ◽

2021 ◽

Vol 861 ◽

pp. 158439

Author(s):

Li Guirong ◽

Wen Haoran ◽

Wang Hongming ◽

Ren Wenxiang ◽

Yan Yuwei ◽

...

Keyword(s):

Mechanical Behavior ◽

Matrix Composites ◽

Microstructural Characteristics ◽

Microwave Assisted ◽

Al Matrix Composites ◽

Al Matrix

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Enhancement on the Tribological Properties of the Multilayer RGO/Al Matrix Composites by Cu-Coating Method

Materials ◽

10.3390/ma14123163 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3163

Author(s):

Fengguo Liu ◽

Ning Su ◽

Renguo Guan

Keyword(s):

Electron Microscope ◽

Tribological Properties ◽

Milled Powder ◽

Wear Loss ◽

Matrix Composites ◽

Tem Analysis ◽

Lubricating Film ◽

Coating Method ◽

Al Matrix Composites ◽

Al Matrix

Multilayer reduced graphene oxide (mrGO) was chemically modified by electroless plating of copper on surface to form mrGO-Cu. The scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis revealed that nano-Cu particles were uniformly dispersed on the surface of mrGO. The mrGO-Cu powders were further utilized as reinforcements for aluminum (Al) matrix and the mrGO-Cu/Al composite was successfully fabricated through clad rolling of milled powder. The tribological properties of the mrGO-Cu/Al composites were explored. The tribological results show that the mrGO-Cu could reduce the friction coefficient and wear loss of mrGO-Cu/Al composites, since the mrGO-Cu participated in lubricating processes due to the formation of a transfer layer on the contact surface. Furthermore, it is found that the composition of mrGO-Cu could significantly influence the tribological properties of the mrGO-Cu/Al composites. The composites with 4% of mrGO-Cu for composites exhibited the best tribological behavior, which transformed from adhesive wear to abrasive wear, due to the formation of a graphite lubricating film.

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Al Matrix Composites Reinforced by Ti and C Dedicated to Work at Elevated Temperature

Materials ◽

10.3390/ma14113114 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3114

Author(s):

Bartosz Hekner ◽

Jerzy Myalski ◽

Patryk Wrześniowski ◽

Tomasz Maciąg

Keyword(s):

Working Conditions ◽

Elevated Temperatures ◽

Aluminium Matrix ◽

Carbon Surface ◽

Matrix Composites ◽

Time Intervals ◽

Aluminium Matrix Composites ◽

Al Matrix Composites ◽

Microstructure Of The Material ◽

Al Matrix

In this paper, the applicability of aluminium matrix composites to high-temperature working conditions (not exceeding the Al melting point) was evaluated. The behaviour of Al-Ti-C composites at elevated temperatures was described based on microstructural and phase composition observations for composites heated at temperatures of 540 and 600 °C over differing time intervals from 2 to 72 h. The materials investigated were aluminium matrix composites (AMC) reinforced with a spatial carbon (C) structure covered by a titanium (Ti) layer. This layer protected the carbon surface against contact with the aluminium during processing, protection which was maintained for the material’s lifetime and ensured the required phase compositions of Al4C3 phase limitation and AlTi3 phase creation. It was also proved that heat treatment influenced not only phase compositions but also the microstructure of the material, and, as a consequence, the properties of the composite.

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