Industry 4.0 being the new face of manufacturing for future, metal additive manufacturing is a key element in this framework. For metal additive manufacturing, laser-based additive manufacturing ...techniques are dominating today. However, some of the inherent technical limitations associated with these techniques lead to a significant gap between the industrial requirements and the final deliverables. Additive friction stir deposition is a promising alternative that is still in its early stages of development. This review summarizes the vital findings in AFSD with particular emphasis on microstructure evolution and physical properties. The technical limitations of laser-based AM techniques are discussed to describe the role of AFSD in their domain. AFSD is discussed sequentially covering the basic physical process, features, capabilities, and limitations. AFSD, being a solid-state thermomechanical process, results in a refined equiaxed microstructure with enhanced mechanical properties and no signs of porosity and residual stresses. In addition to this, AFSD is capable of depositing large scale components at a high build rate that leads to cost and energy-efficient fabrication. The existing limitations of the process are discussed with the scope for future improvements. This critical review concludes with the suggested strategies for the widespread adoption of AFSD.
The manufacturing industries in modern era are competing to reduce cost of production by employing innovative techniques, one being hard turning. In hard turning process, the work piece is heat ...treated to the required hardness in the initial stage itself and near net shape is arrived directly by hard turning process. Hard turning reduces manufacturing lead time by excluding the normal cost incurring processes such as, turning, heat treatment, finish grinding etc. In this experimental investigation hard turning process is assisted with minimal cutting fluid application technique, which reduces cutting fluid usage to a minimum of 6-8 ml/min. Soya bean oil based emulsion was used to make the hard turning environment friendly. The oil was prepared by adding additives, which will enhance the desirable properties of the oil for hard turning. Response surface methodology was used for optimization of cutting parameters and for the prediction of surface roughness. A central composite design was implemented to estimate the second-degree polynomial model. The cutting parameters considered for experimentation were cutting speed, feed rate and depth of cut. The surface roughness was considered parameter for prediction. Surface roughness predicted by the response Surface Methodology matched well with the experimental results.
This paper presents the machining characteristics of AA6061/(0-9 wt%) ZrB
2
+ ZrC aluminium metal matrix composites using polycrystalline Diamond(PCD). In the present investigation, AMCs were ...fabricated by in situ reactions between K
2
ZrF
6
, KBF
4
and SiC particles. The electric stir casting furnace was used to fabricate the AMCs under a controlled environment. X-ray diffraction patterns (XRD) and field emission scanning electron microscope (FESEM) were used to ascertain the formation of ZrB
2
and ZrC particles in the AMCs. FESEM micrographs confirmed the uniform distribution of ZrB
2
and ZrC particulates along with good interfacial bonding with matrix aluminium alloy. The effect of varying wt% of ZrB
2
+ ZrC along with cutting speed, feed and depth of cut on machining forces and surface roughness were analysed. FESEM was used to study the morphology of cutting tool, machined surface and chip formation. It was observed that cutting forces reduce with increase in cutting speed due to decrease in built-up edge (BUE) formation and deprivation of dislocation density. The tool wear increased with increase in cutting speed, depth of cut and ZrB
2
+ ZrC content due to the increase in abrasive action of ceramic particles and reduction of stable BUE.
In this research work, an effort was made to predict the dry sliding wear response of AlMg1SiCu alloy hybrid composites which were reinforced with 10% Silicon carbide particles (SiC) together with ...weight fractions of 3, 6 and 9% of self-lubricant molybdenum disulphide particles (MoS
2
) through melt stir casting. The wear behaviour of the hybrid composite samples was evaluated based on Box-Behnken design on pin-on-disc tribometer without lubrication. The output response weight loss was employed to train the neural network model in ANFIS back-propagation algorithm. The weight loss of 9% MoS
2
hybrid composite reduced at low sliding speeds, due to the development of shallow sliding grooves and MoS
2
-lubricated tribolayer. Scanning electron micrographs and EDS of the AlMg1SiCu alloy hybrid composites revealed a uniform distribution of SiC and MoS
2
particles. The tensile strength of the as-cast hybrid composites increases as the wt.% of MoS
2
particles increases, according to the tests. However, the addition of MoS
2
improved the hardness of the hybrid composites until it reached 6 wt.%, after which it decreased slightly. Weight loss and coefficient of friction decreased by addition of self-lubricant MoS
2
in the matrix material. Worn-out surface of the hybrid composite shows the controlling wear mechanisms of the composites, and well-trained ANFIS model could accurately predict the responses better when compared with the response surface methodology model.
In this study, mixed mode solar dryer of forced convection type, integrated with a CuO nanoparticle coated flat plate solar collector was developed and its effectiveness of drying maize under the ...meteorological conditions of Coimbatore, India was evaluated. The aforementioned setup entails a solar collector (flat plate type) with 3 drying trays and a centrifugal blower. The conventional solar absorber plate was made up of aluminium, which was coated with black paint. Another modified solar absorber plate was made up of aluminium with a coating of black paint with two different vol% of CuO nanoparticles (0.02% and 0.04%), for improving the heat transfer rate. Performance tests on the modified dryer were carried out at constant air flow rate (1.5 m3/min) and the results were compared with the conventional type. The efficiency of the collector got improved by 4% while using black paint with 0.04 vol% of CuO nanoparticle coated absorber. Also the drying time got reduced by 6%, when compared to conventional type dryer. Also the collector temperature recorded in the black paint with 0.04 vol% CuO nano-particle coated collector was higher compared to black paint coated and black paint with 0.02 vol% CuO nanoparticle coated collector.
•A mixed mode CuO nanoparticle coated flat plate solar collector was developed.•Its performance for drying maize was evaluated.•The modified solar absorber plate was made with a coating of CuO nanoparticles.•The collector efficiency improved by 4% for 0.04 vol% CuOnp coated absorber.•The drying time of 0.04 vol% CuOnp coated absorber was reduced by 6%.
The predominant aim of the research has been meant to evaluate cutting characteristic features of machining on AA6061/ZrB2-ZrC hybrid composite metal matrix with polycrystalline diamond tool. Though ...researchers understand, Taguchi would be used for dry turning operations to find the optimal cutting parameters. We have used the Taguchi L16 orthogonal array in the current investigation to evaluate the cutting characteristics. Through this work it's analyzed that the optimal cutting as well as main cutting parameters actually affects the cutting performance. In order to understand the effectiveness of investigational optimization, confirmatory tests have been carried out hybrid composites fabrication composite has proved that it has better machining characterization. Hence, the fabricated composite can be recommended for applications especially hypersonic flight and rocket propulsion systems and because of the presence of hard ceramic material it is used commercially for the manufacture of cutting tools inserts.
Grinding, the commonly used final finishing process across various industries for preparation of surfaces, uses an abrasive cutting wheel. Surface finish is the most commonly used index of final ...product quality in terms of aesthetics, corrosion resistance and others. The final surface finish of the grounded components depends on the cutting conditions of the grinding wheel and the machining parameters. Grinding wheel loading and wheel wear are the significant factors that determine the cutting conditions of the grinding wheel. Grinding wheel dressing is usually carried out to restore the original cutting conditions of the wheel. Speed, feed and depth of cut are the various machining parameters that affect the final surface finish. This paper aims to develop a predictive as well as optimization model by integrating Artificial Neural Network (ANN) with Genetic Algorithm (GA). Experiments were conducted on cylindrical grinding machine with Silicon Carbide grinding wheel. Speed, feed and depth of cut were selected as the three machining parameters with three different levels. Multilayer Normal Feed Forward ANN model of type 3-5-1 was considered for the prediction of surface roughness. Predicted values using the ANN model showed good agreement with the experimental values of surface roughness. Using ANN model alone could have the drawback that local minima based on initial parameters/training can be mistaken for the global optimum. Integrating Genetic Algorithm (GA) with ANN model overcomes this to a great extent. Such a hybrid technique can result in global optimal point of the machining parameters thereby leading to minimum surface roughness. The experimental results show the feasibility of the proposed method in the predictive modeling and optimization of grinding parameters.
Al 4043 is commonly used as a filler material for welding of aluminium-based components. In the present research work, Al 4043/xTiB
2
(titanium diboride) microcomposites (
x
= 2, 4, 6, 8 and 10 wt%) ...are fabricated by dilution of Al 4043/10TiB
2
in situ master composites synthesized by salt-melt reaction. To synthesize the nanocomposites, in situ Al 4043/10TiB
2
composites are re-melted, diluted and ultrasonic-treated for 5 min. The microstructural analysis revealed that ultrasonic treatment (UT) is beneficial on improving the dispersion and refinement of TiB
2
particles. UT of Al 4043/2TiB
2
composites reduced the size of TiB
2
particles from ~ 1270 to ~ 25 nm. At the same time, the efficiency of UT on agglomerate breakage and particle size reduction decreases with the increase in amount of reinforcement. The hindrance generated by increased amount of reinforcements to ultrasonic wave propagation and allied impairment on cavitation implosion is proposed as the reason for the reduction in efficiency of UT. The mechanical property analysis revealed that UT-assisted size reduction and agglomerate breakage of TiB
2
particles significantly increase both hardness and compressive strength of in situ composites. The results revealed that the compressive strength of TiB
2
-reinforced Al 4043/10TiB
2
micro- and nanocomposite increased up to ~ 90 and ~ 150 MPa, respectively
.
Also, a significant improvement in hardness was observed in the reinforced Al 4043/10TiB
2
micro- and nanocomposites by ~ 94% and ~ 98%, respectively, compared to the monolithic alloy.
In the present work, AA6061 aluminum matrix composite (AMCs) was fabricated by mixing AA6061 matrix with the byproducts of in situ reaction namely ZrB2 and ZrC sub micron particles. The in situ ...reaction took place between K2ZrF6, KBF4 and SiC particles. The Fabrication of AMCs was done under a controlled environment using an electric stir casting furnace. The mechanical and microstructural properties of as cast AMCs were investigated by Differential thermal analysis (DTA), x-ray diffraction patterns (XRD), Field emission scanning electron microscope (FESEM), Electron back-scattered diagram (EBSD), and transmission electron microscopy (TEM). The in situ formation of ZrB2 particles in AA6061 aluminum matrix occurred at a temperature of 852.8 °C and ZrC particles at 1116.8 °C, which was confirmed by Heat flow curves obtained by differential thermal analysis (DTA). The formation of ZrB2 and ZrC particulates in the AMCs is also ascertained by XRD and FESEM results. The homogeneous distribution of in situ formed ZrB2 and ZrC particles in the AMCs with good interfacial bonding was confirmed from the FESEM micrographs. The refinement of grains of aluminum matrix by the in situ formed ZrB2 and ZrC particles was proved by EBSD maps. The in situ formed ZrB2 and ZrC particles in the AMCs exhibited hexagonal and spherical shapes, thermodynamically stable structure, increased the microhardness and UTS of in situ fabricated AMCs.
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