Influence of AZ91 alloy reinforced with nano B4C particles on microstructural characterization, hardness and tribological properties prepared through powder metallurgy

The aluminium metal matrix composite reinforced with ceramic material of Silicon carbide (SiC) has good mechanical properties. However, aluminium based ceramic composites require improvements in their lubrication and tribological properties. In this study an attempt is made in the development of a new material through powder metallurgy technique by the addition of Graphite, which acts as a solid lubricant. This work investigated the inﬂuence of graphite on the wear behaviour of Al 7075/SiC /X wt.% graphite(X=0, 5 and 10) hybrid composite. The investigation reveals the effectiveness of incorporation of graphite in the composite for gaining wear reduction. The Al 7075 (aluminium alloy 7075) reinforced with SiC –graphite were investigated. The composites were fabricated using powder metallurgy route. The microstructures, material combination, wear and friction properties were analysed by scanning electron microscopy, XRD, and pin-on-disc wear tester. The newly developed aluminium composite has signiﬁcant improvements in tribological properties with a combination of 5% Silicon carbide (SiC) and 5% Graphite. The test reveals that sliding distance of 1000 m and sliding speed of 1.5 m/s with applied load of 5 N result in minimum wear loss of 0.01062g and coefficient of friction as 0.1278.

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Carbon Nanotubes Improves the Tribological Properties of Ni60/Al2O3 Coatings

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.785-786.864 ◽

2013 ◽

Vol 785-786 ◽

pp. 864-871

Author(s):

Shu Xiao ◽

Xi Yun Cheng ◽

De Gui Ma

Keyword(s):

Carbon Nanotubes ◽

Tribological Properties ◽

Microstructural Characterization ◽

Flame Spraying ◽

Dual Roles ◽

Wear Rates ◽

Transmission Electron ◽

Pin On Disk ◽

Wear Tests ◽

Original Coating

Carbon nanotubes (CNTs) was introduced into Ni60/Al2O3coating by flame spraying. The effect of adding CNTs on the tribological properties of the coating was studied by varying the CNTs content as 0.0, 1.5, 3.0 and 4.5 wt% in the Ni60/Al2O3powders. The microhardness tester was used to measure the microhardness of the coating. Wear tests were performed on a pin-on-disk tribometer, to evaluate the tribological properties of the Ni60/Al2O3/CNTs coatings. Microstructural characterization was performed using scanning and transmission electron microscopy. Ni60/Al2O3/CNTs coatings revealed a lower wear rate and friction coefficient compared with the original coating, and their wear rates and friction coefficients showed a decreasing trend with increasing mass fraction of CNTs within the range from 0 to 3.0 wt% due to the effects of the reinforcement and reduced friction of CNTs. The results showed that the CNTs played dual roles in improving the tribological performance of the coating, indirectly by influencing the microstructure and mechanical properties of the coating and directly by acting as a lubricating medium.

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Analysis of tribological properties of graphite and aluminum composite materials prepared by powder metallurgy technique

Materials Express ◽

10.1166/mex.2020.1692 ◽

2020 ◽

Vol 10 (5) ◽

pp. 663-670

Author(s):

Zhigang Wang ◽

Jun Li ◽

Daquan Li

Keyword(s):

Composite Materials ◽

Powder Metallurgy ◽

Friction Coefficient ◽

Tribological Properties ◽

Utilization Rate ◽

Powder Metallurgy Technique ◽

Aluminum Composite ◽

Powder Metallurgy Process ◽

Metallurgy Process ◽

Composite Samples

In order to make full use of the wear resistance and antifriction of the mixed reinforced particles, improve the performance and utilization rate of the composite material, and reduce its wear amount, in this study, graphite and aluminum composite materials with different graphite concentration were prepared by powder metallurgy process. On this basis, the influence of different graphite concentration on the friction coefficient and wear amount of composite samples and different load on the wear amount of composite materials were discussed and analyzed. The results show that with the increase of graphite content, the friction coefficient and wear amount of the composite will decrease correspondingly. When the load is less than 30 N, the wear curve of the sample changes steadily. When the load is more than 30 N, the wear will increase sharply. Therefore, the analysis of the tribological properties of the graphite and aluminum composites based on the powder metallurgy process plays an important role in improving the utilization rate of the composite and reducing its wear.

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Fabrication and Tribological Properties of Copper Matrix Solid Self-Lubricant Composites Reinforced with Ni/NbSe2 Composites

Materials ◽

10.3390/ma12111854 ◽

2019 ◽

Vol 12 (11) ◽

pp. 1854

Author(s):

Fei-xia Zhang ◽

Yan-qiu Chu ◽

Chang-sheng Li

Keyword(s):

Powder Metallurgy ◽

Friction Coefficient ◽

Wear Rate ◽

Tribological Properties ◽

Friction And Wear ◽

Copper Matrix ◽

Wear Properties ◽

Disk Friction ◽

Friction Reducing ◽

Properties Of Composites

This paper presents a facile and effective method for preparing Ni/NbSe2 composites in order to improve the wettability of NbSe2 and copper matrix, which is helpful in enhancing the friction-reducing and anti-wear properties of copper-based composites. The powder metallurgy (P/M) technique was used to fabricate copper-based composites with different weight fractions of Ni/NbSe2, and tribological properties of composites were evaluated by using a ball-on-disk friction-and-wear tester. Results indicated that tribological properties of copper-based composites were improved by the addition of Ni/NbSe2. In particular, copper-based composites containing 15 wt.% Ni/NbSe2 showed the lowest friction coefficient (0.16) and wear rate (4.1 × 10−5 mm3·N−1·m−1) among all composites.

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Effect of Presence of Nano-Size Alumina Particles on the Properties of Elemental Magnesium

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.23.171 ◽

2005 ◽

Vol 23 ◽

pp. 171-174 ◽

Cited By ~ 6

Author(s):

X.L. Zhong ◽

Manoj Gupta

Keyword(s):

Powder Metallurgy ◽

Uniform Distribution ◽

Dimensional Stability ◽

Microstructural Characterization ◽

Alumina Content ◽

Alumina Particles ◽

Higher Temperature ◽

Characterization Studies ◽

Nano Size ◽

Composite Samples

In present study, elemental magnesium was reinforced with nano-size alumina particles (50-nm). The composite samples were synthesized using the technique of powder metallurgy and the effect of extrusion temperature and sintering on the end properties was particularly investigated. The results of microstructural characterization studies confirmed the presence and reasonably uniform distribution of alumina particles. Results obtained from extruded unsintered samples revealed that the hardness and dimensional stability of magnesium increases with an increasing presence of alumina particles while the 0.2%YS, UTS and ductility deteriorated. Results further revealed that including sintering step and extruding at higher temperature lead to an increase in dimensional stability, hardness, 0.2%YS, UTS and ductility for an alumina content as low as one percent by weight.

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Enhancing Properties of Aerospace Alloy Elektron 21 Using Boron Carbide Nanoparticles as Reinforcement

Applied Sciences ◽

10.3390/app9245470 ◽

2019 ◽

Vol 9 (24) ◽

pp. 5470

Author(s):

Sravya Tekumalla ◽

Ng Joo Yuan ◽

Meysam Haghshenas ◽

Manoj Gupta

Keyword(s):

Mechanical Properties ◽

Boron Carbide ◽

Compressive Loading ◽

Hot Extrusion ◽

Microstructural Characterization ◽

Thermal Insulating ◽

Damping Characteristics ◽

B4c Particles ◽

Superior Mechanical Properties ◽

Melt Deposition

In this study, the effect of nano-B4C addition on the property profile of Elektron 21 (E21) alloys is investigated. E21 reinforced with different amounts of nano-size B4C particulates was synthesized using the disintegrated melt deposition technique followed by hot extrusion. Microstructural characterization of the developed E21-B4C composites revealed refined grains with the progressive addition of boron carbide nanoparticles. The evaluation of mechanical properties indicated a significant improvement in the yield strength of the nanocomposites under compressive loading. Further, the E21-2.5B4C nanocomposites exhibited the best damping characteristics, highest young’s modulus, and highest resistance to ignition, thus featuring all the characteristics of a material suitable for several aircraft applications besides the currently allowed seat frames. The superior mechanical properties of the E21-B4C nanocomposites are attributed to the refined grain sizes, uniform distribution of the nanoparticles, and the thermal insulating effects of nano-B4C particles.

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