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Mechanical bonding between dissimilar metals is challenged due to the differences in their properties. In this paper, the influence of tapering in friction welding (FW) between AA6063 and AISI304L and the effect of welding parameters are investigated to obtain quality joints. Different experiments were carried out for this study with main influencing parameters such as upset pressure (UP), friction time (FT) and friction pressure (FP). Tensile test, impact test and microhardness distribution along weld zone, heat affected zone (HAZ), parent zone of welded joint were evaluated and the results were compared. Microstructure study observed by scanning electron microscopy (SEM) revealed the bonding between two dissimilar metals. Fractography analysis showed the dimple rupture. Tensile strength and peak load increased with increasing friction pressure. The formation of intermetallic compounds at the weld interface was confirmed with the EDX spectrum. The tapering on faying surface of SS304L specimen reduced the friction time needed for sound weld joints and increases the properties of joint. Since no appreciable researches have been done on the joining between AA6063 and AISI304L with minimum working pressure through FW, special attention was given to this work with a taper on faying portion. The minimum parameters required for the joining were also understood through this investigation.

The essence of the Hadith of the Holy Prophet (S.AW) is its fame. When there is Tafarud in a Hadith, the scholars scrutinize it with great concern to detect whether Tafarud is incidental or the Ravi has committed some mistake. The status of the Hadith is established on the basis of Tafarud. There is no specific rule or formula for it, rather every Tafarud is decided permanently on the basis of circumstances. In this paper I have mentioned Imam Tabrani way of Tafarud. I have explained different forms of Tafarud in his book Al Mujam-ul- Awsat. I have also explained with example that Tafarud is accepted sometimes wile rejected at others.

Purpose The purpose of this paper is to minimize the mean flow time in open shop scheduling problem (OSSP). The scheduling problems consist of n jobs and m machines, in which each job has O operations. The processing time for 50 OSSP was generated using a linear congruential random number. Design/methodology/approach Different evolutionary algorithms are used to minimize the mean flow time of OSSP. This research study used simulated annealing (SA), Discrete Firefly Algorithm and a Hybrid Firefly Algorithm with SA. These methods are referred as A1, A2 and A3, respectively. Findings A comparison of the results obtained from the three methods shows that the Hybrid Firefly Algorithm with SA (A3) gives the best mean flow time for 76 percent instances. Also, it has been observed that as the number of jobs increases, the chances of getting better results also increased. Among the first 25 problems (i.e. job ranging from 3 to 7), A3 gave the best results for 13 instances, i.e., for 52 percent of the first 25 instances. While for the last 25 problems (i.e. Job ranging from 8 to 12), A3 gave the best results for all 25 instances, i.e. for 100 percent of the problems. Originality/value From the literature it has been observed that no researchers have attempted to solve OOSPs using Firefly Algorithm (FA). In this research work an attempt has been made to apply the FA and its hybridization to solve OSSP. Also the research work carried out in this paper can also be applied for a real-time Industrial problem.

Hastelloy-X is a nickel-based superalloy predominantly using in engine combustion zone parts of gas turbines. Micro-holes are drilling to the surface of these parts for air-cooling passageways to improve part-life by reducing thermal fatigue. Laser, micro-electric discharge machining (µEDM), and micro electrochemical machining (µECM) are the major processes for creating holes in superalloys. Yet, if used individually, these techniques could end up with faulty holes. The sequential application of multiple drilling methods for hole-making will eliminate the defects. In this work, micro-holes have drilled on Hastelloy-X by using a laser in sequence with μEDM and laser in sequence with μECM. Holes produced by these two-hybrid approaches are later compared for productivity and quality features. Both form and productivity factors have been estimated, and optimal input combinations for each response have been identified from the mean analysis. The Pareto-Analysis of Variance has been used to determine the critical factors for each response. A detailed characterization study has been done to ensure the surface integrity of the holes. It has been found that micro-holes formed by sequential laser processing with μEDM improve the responses compared to the individual μEDM outputs. A similar improvement has also observed in laser combined with µECM holes concerning individual µECM. Both results collectively indicated that the novel sequential laser approach with µEDM is more efficient than the sequential application of laser with the µECM. This study provides clear guidance for the sequential micro-drilling of Hastelloy-X using numerous non-traditional drilling approaches.

This work describes the effect of newly introduced faying surfaces on the microstructure and the mechanical properties of dissimilar weld joints of AA6063 and AISI304L alloys that fabricated through the rotary friction welding process (RFW). The experiments were done as six different experimental methods (‘A’ to ‘F’) at 1300 rpm rotation, 18 MPa friction pressure (FP), 24 MPa upset pressure (UP) and 5 sec friction time (FT) with the faying surfaces of hemispherical bowl and thread of 1 mm pitch on the weld specimens. The fabricated joints and the weld zones were characterized by macro and micro-study, Energy Dispersive X-ray Spectroscopy (EDS) spectrums, tensile properties, Vickers microhardness, impact toughness and fractography. The results showed that these faying surface modifications strengthen the bonding between the weld specimens and influences the performance of the joints. The hemispherical bowl showed better results than the threaded surfaces. Axial shortenings were within the acceptable limit in the range of 20–27 mm. Macro and microstructural studies showed the defect-free weld joints and the strong bonding between AA6063 and AISI304L alloys. The hemispherical faying surface on AISI304L alloy formed a U-shaped weld interface (WI) in the dissimilar joints. EDS proved the formation of the Fe-Al intermetallic and the element ‘O’ at weld zone. The joint efficiency for all the methods was around ≥ 100%. Maximum tensile strength was recorded as 238 MPa for method ‘F’. The threaded surface showed good hardness property nearby WI and method ‘A’ yielded maximum impact toughness for the joint.

Joining of dissimilar alloys is demanded industrial applications and is effectively possible with the friction welding (FW) process. In this work, SS304L alloy rods were electroplated with silver (Ag), nickel (Ni) and chromium (Cr) and joined with AA6063 at various upset pressures (UP) (18, 21, 24 MPa) through friction welding process. The interlayer produced by the electroplating process was considered as the third element between AA6063 and SS304L during the FW. The results obtained through weld microstructures, fracture images, energy-dispersive X-ray spectroscopy, tensile properties, joint efficiency, Vickers microhardness and Charpy V-notch test of the fabricated dissimilar joints are discussed here. Fracture study showed the dimple fracture. The maximum strength and axial shortening were obtained as 216 ± 8 MPa and 27 mm, respectively. Maximum joint efficiency was achieved for Cr interlayer as 105 ± 4% at 24 MPa UP, which also showed a 1.79 tensile-to-yield (TS/YS) ratio. UP of 24 MPa improved ductile nature of joint. Ag and Ni joints rendered poor elongation. FW of chromium-electroplated specimen gave maximum weld performance than that of others. Ag interlayer at 18 MPa UP showed good hardness. Maximum impact energy observed by Cr at 24 MPa UP was 35 J. The novelty of the work is to frictionally weld the dissimilar metals of ϕ12 mm rods with Ag, Ni, Cr interlayer at welding pressures in view of safety and energy consumption. There were the changes in the microstructure and mechanical properties of joints when the interlayers, UPs changed.

This paper presents a detailed investigation on the formation of θ′ and θ″ precipitates in the Cryorolled (CR) material of AA2219 alloy and the Friction Stir (FS) welded portion of CR AA2219 and their influence on material characterizations. The ultrafine grain formation and precipitate dissolutions in CR AA2219 and FS weld were characterized using optical, Scanning Electron (SEM) and Transmission Electron Microscopes (TEM). X-Ray Diffraction (XRD) was carried out to distinguish the phase changes of base AA2219, CR AA2219 and FS weld portion.

As one of the largest manufacturing sectors, the automotive industry has a deep impact on the society and environment. Automotive products provide mobility to millions and create jobs, but also threaten the environment. Consumer pressure, government regulations, and stakeholder demands for a competitive edge have forced the automotive industry to consider their environmental and social impacts in addition to their economic status. These pressures have led many automotive industry businesses to adopt Sustainable Supply Chain Management (SSCM) practices. Specific practices that are adopted into the traditional supply chain and that help an industry shift towards a sustainable supply chain are called SSCM practices. Firms have difficulty identifying the most useful practices and learning how these practices impact each other. Unfortunately, no existing research has studied the interrelated influences among these practices in the automotive industry, nor from an Indian perspective. The current study aims to give a better understanding of the interrelated influences among SSCM practices with a particular look at the automotive industry. Our research presents views from multiple stakeholders, including managerial, environmental, societal, and governmental associations. We propose a framework model, using the Decision Making Trial and Evaluation Laboratory method, to evaluate automotive industry SSCM practices specifically situated in the emerging economy of India. Through a questionnaire survey with the above-mentioned stakeholders, we find interinfluences and the prominence of the identified practices. A prominence causal relationship diagram is obtained depicting the cause groups and the effect groups of the practices. The differences and similarities between individual perspectives and combined stakeholder perspectives are identified. The results reveal that management commitment towards sustainability and incorporating the triple bottom line approach in strategic decision making are the most influential practices for implementing the sustainable supply chain management. This study provides a foundation for industrial managers to understand the inter influences among the practices and increases the probability of successful implementation of SSCM practices within the automotive industry.

In this paper, parameter optimization of FSW of cryorolled AA2219 alloy was carried out to obtain defect free weld joint with maximum weld strength. To achieve this, artificial neural network (ANN) was used to model the relationship between the input parameters and the mechanical and corrosion properties (output) of the weld joints. The optimal FSW parameters were determined by genetic algorithm (GA). The feasible solution of the GA was tool rotational speed of 1005 rpm, tool travel speed of 20 mm/min and tool tilt angle of 3°. The feasible parameter was used to weld and check the ability of the parameter to produce better weld joint than the L9 orthogonal array parameters. The weld, subjected to the confirmation test, was investigated by means of metallurgical, mechanical, and corrosion testing. This process reduces the costs associated with trial runs to obtain optimal parameters and also the production cost of the cryorolled (CR) plate which is high.

Mechanical, metallurgical and corrosion behaviors of cryorolled (cryo-treated) and untreated aluminium plate AA2219-T87 were examined. After cryorolling, the yield strength, hardness and impact strength of the alloy was improved upto 14%.The ultra fine grain structure was observed in microstructure. The fracture behavior cryorolled material was analyzed with SEM fractograph. The potentiodynamic polarization test was conducted on both untreated and cryotreated alloy. Corrosion results shows that the resistance of the cryotreated alloywas found to be better compared with the untreated alloy, which was also confirmed by SEM. There was no phase changes found in XRD on cryorolled material.