Microstructure, tensile and compression behaviour of B4C particles reinforced Al7075 matrix composites

Abstract This study aims to investigate the tribological behaviour of lamb bone ash (LBA) and boron carbide (B4C) reinforced ZA-27 hybrid metal matrix composites fabricated using a stir casting process. The weight percentage of LBA and B4C particles in the composites were varied from 0-5 wt.%. The composites have been evaluated for density, porosity and microhardness before tribological testing. Dry sliding friction and wear behaviour of composites were studied on a pin-on-disc tribometer by varying load from 10-50 N at a fixed sliding speed of 1 m/s. Also, to investigate the effect of sliding speed on friction and wear behaviour of composites, tests were carried out at 2 m/s and 3 m/s of sliding speed. A scanning electron microscope (SEM) was used for examining the microstructure and worn surface morphology of composite samples. SEM micrographs revealed the presence and homogeneous distribution of reinforcement particles, and energy-dispersive X-ray spectroscopy (EDS) analysis confirmed the presence of LBA and B4C particles in the composites. Composites density decreased, and porosity increased with the addition of reinforcement particles. The microhardness of the 5 wt.% reinforced LBA composite improved by 18.38%, whereas hybrid composite containing (2.5 wt.% LBA + 2.5 wt.% B4C) showed an improvement of 42% compared to the base alloy. The coefficient of friction (COF) and wear loss increased with the increase in load, whereas COF decreased and wear loss increased with the increase in sliding speed. Composites showed superior wear resistance even at higher loads and sliding speeds. SEM micrographs of worn surface revealed adhesion and abrasion type of wear mechanisms. Therefore, with the improvement in wear resistance this developed composite can be used as a bearing material over monolithic ZA-27 alloy in the automotive sector.

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B4C Particles Reinforced Al2024 Composites via Mechanical Milling

Metals ◽

10.3390/met8080647 ◽

2018 ◽

Vol 8 (8) ◽

pp. 647 ◽

Cited By ~ 7

Author(s):

Caleb Carreño-Gallardo ◽

Ivanovich Estrada-Guel ◽

Claudia López-Meléndez ◽

Ernesto Ledezma-Sillas ◽

Rubén Castañeda-Balderas ◽

...

Keyword(s):

Crystallite Size ◽

Mechanical Milling ◽

Aluminum Matrix ◽

High Energy ◽

Milling Process ◽

Homogeneous Distribution ◽

Aluminum Matrix Composites ◽

Matrix Composites ◽

2024 Alloy ◽

B4c Particles

The control of a homogeneous distribution of the reinforcing phase in aluminum matrix composites is the main issue during the synthesis of this kind of material. In this work, 2024 aluminum matrix composites reinforced with boron carbide were produced by mechanical milling, using 1 and 2 h of milling. After milling, powdered samples were cold consolidated, sintered and T6 heat treated. The morphology and microstructure of Al2024/B4C composites were investigated by scanning electron microscopy; analysis of X-ray diffraction peaks were used for the calculation of the crystallite size and microstrains by the Williamson–Hall method. The mechanical properties were evaluated by compression and hardness tests. B4C particles were found to be well dispersed into the aluminum matrix as a result of the high-energy milling process. The crystallite size of composites milled for 2 h was lower than those milled for 1 h. The hardness, yield strength and maximum strength were significantly improved in the composites processed for 2 h, in comparison to those processed for 1 h and the monolithic 2024 alloy.

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Synthesis and Characterisation of B4C Reinforced Al6061 Friction Stir Processed Surface Composites

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.a1164.109119 ◽

2019 ◽

Vol 9 (1) ◽

pp. 2883-2887 ◽

Cited By ~ 1

Keyword(s):

Metal Matrix Composites ◽

Metal Matrix ◽

High Strength ◽

Traverse Speed ◽

Homogeneous Distribution ◽

Matrix Composites ◽

Friction Stir ◽

Surface Composites ◽

B4c Particles ◽

Structurally Stable

Current industrial trends show increased usage of lightweight high strength materials such as Aluminium, Titanium, Magnesium, etc., in their products and components. To achieve an improved service life, particulates reinforced metal matrix composites are being favored over the monolithic alloys. Researchers have reported undesirable defects and interfacial reactions while trying to fabricate such composites using conventional methodologies. This motivates the present work to use friction stir processing, an allied process of friction stir welding, to fabricate metal matrix composites. Structurally stable and most commonly used AA6061 alloy was taken for the experiment. B4C particles were used as reinforcements. Experiments were carried out using different process parameters like tool revolution and tool traverse speed or processing speed along with a constant axial force. The B4C particles were packed into a 1.5 mm groove on the Al6061 plate and friction processing was carried out. The SEM investigations on the composites showed a defect-free microstructure with a homogeneous distribution of reinforcement particles. It was found that the reinforcements increased the tensile strength of the composite by 50%. The hardness and wear-resistant properties of the composites had also improved considerably.

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COMPARISON OF MECHANICAL AND MICROSTRUCTURAL EXAMINATION OF AL7075 COMPOSITES REINFORCED WITH MICRO AND NANO B4C

10.31224/osf.io/reygs ◽

2020 ◽

Author(s):

Krishna Mohan Singh ◽

A. K. Chauhan

Keyword(s):

Mechanical Properties ◽

Aluminum Matrix ◽

Stir Casting ◽

Aluminum Matrix Composites ◽

Matrix Composites ◽

Casting Method ◽

Lightweight Materials ◽

Fine Microstructure ◽

B4c Particles ◽

Microstructural Examination

Due to the demand for lightweight materials in the field of automobiles, aeronautics and some other application, there is a need to develop lightweight materials. For the last few decades, aluminum matrix composites are being developed in order to meet out the demand of the above-mentioned industries. aluminum the above, lightweight material in the form of composites of B4C reinforced in Al7075 alloy is considered for the present investigation. The composite was produced using the stir casting method. In this investigation, the micro and nano B4C particles were used as reinforcements. The fabricated composites were characterized for microstructure and mechanical properties. From the microstructural examination, it was observed that 12% of B4C nanocomposites was having fine microstructure as compared to others. The hardness and strength were found to be maximum for 12 % B4C nanocomposites which impact strength was lowest for 12% micro composites.

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Ultrasonic Vibration-Assisted Laser Directed Energy Deposition of B4C-Ti Composite: Effect of Laser Power and Ultrasonic Vibration

Volume 2: Manufacturing Processes; Manufacturing Systems; Nano/Micro/Meso Manufacturing; Quality and Reliability ◽

10.1115/msec2021-60388 ◽

2021 ◽

Author(s):

Yunze Li ◽

Dongzhe Zhang ◽

Weilong Cong

Keyword(s):

Ultrasonic Vibration ◽

Laser Power ◽

Energy Deposition ◽

Pure Titanium ◽

Matrix Composites ◽

Titanium Matrix ◽

Composite Effect ◽

Directed Energy Deposition ◽

B4c Particles ◽

Directed Energy

Abstract Compared with pure titanium, ceramic reinforced titanium matrix composites (TMCs) have the advantages of higher microhardness, higher wear resistance, and better load endurance properties, which enable their further applications under severe friction and cyclic loading conditions. B4C-Ti composite, as a kind of TMCs, has been fabricated by laser directed energy deposition (DED) technology. However, there are still some problems needed to be solved. First, the B4C particles are not fully melted. It suppresses the reactions between B4C and titanium and reduced the generation of TiB and TiC during the fabrication, which deteriorates the hardness of the B4C-Ti composite. Second, the reinforcement materials are not evenly distributed in the titanium matrix, which damages the performance of the B4C-Ti composite. In this study, B4C-Ti composite parts are fabricated by the ultrasonic vibration-assisted laser DED process. The effects of laser power and ultrasonic vibration on the phase compositions, microstructure, and hardness are investigated.

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On Carbide Particle Reinforced Al Composites Fabricated by Pressureless Infiltration Technique

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.971 ◽

2005 ◽

Vol 475-479 ◽

pp. 971-974

Author(s):

Kon Bae Lee ◽

Ho Sup Sim ◽

Hyung Ryul Yang ◽

Hoon Kwon

Keyword(s):

Carbide Particle ◽

Pressureless Infiltration ◽

Strengthening Effect ◽

Matrix Composites ◽

B4c Particles ◽

Infiltration Technique ◽

Al Matrix Composites ◽

Effective Reinforcement ◽

Carbide Particles ◽

Al Matrix

5052 Al matrix composites reinforced with carbide particles (SiC, TiC, and B4C) were fabricated by the pressureless infiltration and the tensile properties were analyzed. The strength values in the control Al were significantly increased over those of the commercial alloy while the strain to failure of the former decreased. Strength values in the composite reinforced with carbide particles were further increased compared to the control alloys. It was observed that strengthening effect by an addition of reinforcement varied with according to reinforcement types. By relative comparison, both TiC and B4C particles may be effective reinforcement compared to SiC particles in Al matrix composites.

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