Abstract In order to improve the wear and frictional behavior of the aluminum metal matrix composites, carbon nanotube, and fly ash were added as reinforcements. Powder metallurgy technique was used to fabricate the hybrid metal matrix composites. Experimentations were carried out using pin on disc type wear test rig. The analyzed experimental results showed that, in comparison to the pure aluminum and mono reinforcement combination, the wear loss and coefficient of friction of hybrid metal matrix composites were greatly reduced. It was noted that compared to pure aluminum wear loss was decreased to 89.58%, 86.97%, 83.3% by adding 0.25, 0.5, 0.75 wt% carbon nanotube (CNT), respectively. By the addition of 4, 8 and 16 wt% FA to pure Al wear loss was decreased to 83.85%, 89.58%, and 78.12%, respectively. It was also noted that compared to Al/8 wt% FA mono reinforced composites, wear loss was decreased to 77%, 71.26%, and 53.22% with the addition of 0.25, 0.5, 0.75 wt% CNT, respectively. With the addition of 4, 8, 16 wt% FA, wear loss decreased to 81%, 88%, and 75% over Al/0.25 wt% CNT composites, respectively. The microstructural study of the worn‐out surfaces revealed low abrasive and adhesive wear by the presence of carbon nanotubes and fly ash in aluminum metal matrix. The reinforcing mechanisms of the wear and frictional properties were also discussed.

A brass material, C377, was rolled to reduce the thickness to form a plate. In this investigation, a simulation is carried out for the flat rolling process of brass material to find the influence of various process parameters on the hardness (Hv). Von Mises stress (MPa) has been analyzed. The parameters considered for this investigation are roller diameter (mm), temperature ( oC), percentage reduction (%) and speed (RPM). The effect of these input parameters has been critically analyzed using the Taguchi method. It has been found that roller diameter and temperature are the most crucial process parameters affecting the hardness value. It is analyzed for different parameters. Taguchi technique is used to find out the best parameter value for roller diameter, temperature, percentage reduction, and speed of the rollers to optimize the hardness and Von Mises stress. The rolling of brass produced a 175Hv hardness and a spread of 1.6mm at a 64 MPa Von Mises stress level when the process parameters were at optimum values.

In this work, powder metallurgy is used to produce hybrid aluminium composites reinforced with 0.25, 0.5 and 0.75 wt% carbon nanotubes (CNTs) along with 4 wt% of Fly ash (FA). The green composites are subjected under different sintering temperature and sintering time to analyse the effect on the hardness property. The microstructure study is done using scanning electron microscope. The results indicated that sintering temperatures have the predominant effect on hardness properties. The sintering time has predominant effect only up to certain limit. The hardness decreased with increase in the amount of CNTs for all sintering temperature. The hardness and compression properties are improved pure aluminium. The microstructural investigation revealed good bonding between the reinforcements and matrix materials.Copyright (c) 2022 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Smart and Sustainable Developments in Materials, Manufacturing and Energy Engineering

In the current work, the authors aim to present an insight on the role of cobalt (Co) doping for the structural, morphological, and linear and nonlinear optical (NLO) properties of CdO thin films. The films were prepared using the spray pyrolysis (SP) technique, and the weight % of Co (x) was varied from 0–10. The structural properties of the films were confirmed by the powder X-ray diffraction (P-XRD) studies and are polycrystalline with a cubic structure and a lattice parameter of 0.4658 nm. As Co content in CdO films increases, cluster grain size and porosity decrease significantly, as seen in surface topographic and nanostructural analysis. Through the Burstein–Moss shift, the optical band gap “Eg” in Co: CdO film decreases from 2.52 to 2.05 eV with the increase in Co-doping. To study the NLO parameters, open aperture (OA) and closed aperture (CA) Z-scan measurements were performed using the diode-pumped solid-state continuous wave laser excitation (532 nm), and with the increased Co-content, the NLO parameters—nonlinear absorption coefficient (β∼10−3 cm/W), nonlinear refractive index n 2 ∼ 10−8 cm2/W), and the 3rd-order NLO susceptibility χ 3 ∼ 10−7 to 10−6 e.s.u.) values were determined and found to be enhanced. The maximum NLO parameters achieved in the present study with increasing Co concentration on CdO nanostructures prepared by the SP method are found to be the highest among the reported values and suggest that processed films are a capable material for optoelectronic sensor applications.

Dry sliding wear characteristics of aluminium nano-composites reinforced with different wt. % of multiwall carbon nanotubes (0.25, 0.5, 0.75 wt. %) and fly ash (4, 8, 16 wt. %) produced by powder metallurgy were investigated. ANOVA and Taguchi methods of design of experiment technique were successfully used to determine the predominant factors and optimisation of the testing parameters on wear. MWCNT (wt. %) and FA (wt. %) was found to be the predominant parameter affecting wear loss with percentage contribution of 43.71% and 30.78%. The results of Taguchi indicate the optimized values of wear parameters were 0.25wt. % MWCNT, 8 wt. % FA, 2 h ball milling, 6 h sintering, 10 N applied load, 200 rpm sliding speed and 500 m sliding distance. The microstructure of composites exhibited well dispersion of the reinforcements in the aluminium matrix. The study of worn surfaces revealed minor grooves and delamination wear due to abrasive and adhesive wear mechanisms.

The densification and compression behaviour of multi-walled carbon nanotubes (MWCNT) and flyash (FA) reinforced composites fabricated by powder metallurgy method were analysed. MWCNTs (0.25,0.5,0.75 wt%) and FA (4 wt%) were blended with aluminium matrix using ball milling technique and compacted at loads of 100,120 and 140 kN and sintered at 500 degrees C for 6 h under argon atmosphere. Experimental results show that density and hardness increased with the compaction pressure. Microstructural observations revealed good bonding between particles. Compression strength test revealed improved compression properties over unreinforced matrix material. (c) 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Smart and Sustainable Developments in Materials, Manufacturing and Energy Engineering.

In this paper properties of Al metal matrix composites reinforced with carbon nanotubes (CNTs) and fly ashes (FAs) synthesized by powder metallurgy technique were investigated. Density, hardness and compression tests were carried out for the mechanical properties of the specimens. The experimental results showed that addition of FA increases hardness up to 8 wt. % and then decreases while hardness of the composite decreases with increase in CNT content. The results also showed that addition of FAs decreases density values while, addition of CNTs increases density of the composites. The compression strength properties of the composites improved over matrix material.With the aid of scanning electron microscope it was observed that CNTs and fly ashes were well dispersed and embedded in the matrix.XRD and EDS results showed no carbide formation or contamination during the processing of the composites

In this paper, pure aluminium metal matrix composite was fabricated using powder metallurgy, where MWCNT and fly ash used as reinforcing materials. The density and hardness of specimen were calculated and influence of fly ash and MWCNTs on them was discussed. Compression strength of the composites was measured by compression test. It was observed that hardness had increasing effect for certain weight percentage of Fly ash and above that level showed the negative effect on them. The increased ball milling time resulted in well dispersion of the reinforcements. Compressive strength test revealed that addition of MWCNT along with fly ash was resulted in the improvement of the strength of the composite compared to pure Al.

In this study, prediction of density and hardness properties using artificial neural network (ANN) and micro structural evolution of multi walled carbon nano tubes (MWCNT) and fly ashes (FA)/Al composites produced by powder metallurgy were investigated. The influence of content (wt.%) of reinforcements(MWCNTs and FA), ball milling time and sintering time on the mechanical properties were experimentally determined by measuring density and hardness values which are the outputs obtained from the artificial neural network. It was found that amount of reinforcements, ball milling time and sintering time play a major role in dispersion and enhancement of the properties. It was also demonstrated that ANN model is a powerful prediction technique to predict the mechanical properties of the composites. Blend powder morphology and sintered composite structure were investigated by scanning electron microscope (SEM). It was found that reinforcements were well dispersed for prolonged ball milling time and sintering time.

In this work, carbon nano tube(CNT) –Fly ash(FA) reinforced aluminium composites were fabricated by powder metallurgy technique. Green compacts of Al-16wt.% FA 0.75 wt.% CNT composite were fabricated under varying compaction loads were sintered over a series of temperatures (300°C,400°C 500◦C) and sintering time(1,3 and 6 hr) to analyse the effect of sintering temperature and sintering time. The surface morphology was studied using scanning electron microscope for analyse the distribution of reinforcements. Scanning electron microscopy (SEM) analysis revealed the uniform dispersion of FA-CNTs in the composite samples. Hardness and density properties of the composites are also evaluated. It was found that the composite prepared at sintering temp 500 ̊C and sintering time 6 hr showed good result.