Qasim Murtaza

Forecasting product returns for recycling in Indian electronics industry

Purpose - – The purpose of this paper is to develop a model for forecasting product returns to the company for recycling in terms of quantity and time. Design/methodology/approach - – Graphical Evaluation and Review Technique (GERT) has been applied for developing the forecasting model for product returns. A case of Indian mobile manufacturing company is discussed for the validation of this model. Survey conducted by the company and findings from previous research were used for data collection on probabilities and product life cycle. Findings - – Product returns for their recycling are stochastic, random and uncertain. Therefore, to address the uncertainty, randomness and stochastic nature of product returns, GERT is very useful tool for forecasting product returns. Practical implications - – GERT provides the visual picture of the reverse supply chain system and helps in determining the expected time of product returns in a much easier way but it requires probabilities of different flows and product life cycle. Both factors vary over a period, so require data update time to time before implementation. Originality/value - – This model is developed by considering all possible flows of sold products from customer to their reuse, store or recycle or landfill. First time this type of real life flows have been considered and GERT has been applied for forecasting product returns. This model can be utilized by managers for better forecasting that will help them for effective reverse supply chain design.

Experimental Analysis of Spray Dryer Used in Hydroxyapatite Thermal Spray Powder

The spray drying process of hydroxyapatite (HA) powder used as a plasma spray powder on human hip implants was examined. The Niro-Minor mixed spray dryer was studied because it incorporates both co-current and counter-current air mixing systems. The process parameters of the spray drying were investigated: temperature, flow rate of the inlet hot air in the spray dryer, viscosity of feed/HA slurry, and responses (chamber and cyclone powder size, deposition of powder on the wall of spray dryer, and overall thermal efficiency). The statistical analysis (ANOVA test) showed that for the chamber particle size, viscosity was the most significant parameter, while for the cyclone particle size, the main effects were temperature, viscosity, and flow rate, but also their interaction effects were significant. The spray dried HA powder showed the two main shapes were a doughnut and solid sphere shape as a result of the different input.

A Novel Manufacturing Route for Automobile Parts through Two-Wire-Arc Thermal Spray Process

The present work deals with a novel manufacturing route that can be used to fabricate automobile sheet parts such as bonnet/bumper by metal alloy coating through two-wire-arc thermal spray (TWATS) process. Later the coating is supported with fiber through cladding process and becomes a freestanding composite coating. The coating has a metallic look and is free from oxidation. This novel manufacturing process is rapid and customized. A case study, where aluminum alloy wire was used to produce freestanding coating, was performed by response surface method optimization of the two-wire-arc spray process factors: the voltage, current, spray distance, gas pressure, and selection of mold/substrate material that was used to fabricate automobile bonnet. Initial experiments were performed on the four different substrates materials, viz., steel, aluminum, ceramic, and graphite; the graphite substrate showed some promising results and was selected to run the experimental array to optimize the process parameters. Spray distance more than 150 mm, voltage 30 V, current 250 A, and primary atomizing gas (nitrogen) pressure 100 psi (0.689 MPa) may be used. The freestanding aluminum coating was evaluated analyzing its performance, in terms of desirable microstructure and mechanical properties.

Machinability of phosphorous containing sintered steels

Abstract Study of the machinability characteristics of porous sintered materials has received far less attention during the last decades, presumably due to powder metallurgy’s greatest advantage over other manufacturing methods in eliminating completely or minimising greatly machining and also perhaps due to lack of any standard test method developed for machinability studies. However, many parts because of intricate design, require machining afterwards. Thus, there is a renewed interest in machinability characteristics of sintered porous materials. Various investigations on machinability studies of sintered ferrous materials have been reviewed in this study. Finally, the effect of some usual additives and microstructural modification on the machinability of sintered and heat-treated steels has been examined. The method used was time taken by a drill of standard dimension before it broke down. Increasing C-content was found to have marginal while usual alloying elements like Cu, Ni, etc. had significant effect on machinability characteristics of sintered steels. It has been concluded that combination of parameters affecting machinability of P/M materials may prove to be beneficial and effective method to control machining characteristics of sintered steels.

Triple bottom line performance evaluation of reverse logistics

Purpose The paper aims to incorporate the relationship of reverse logistics into the economic, environmental, and social sustainability, known as triple bottom line and developed a framework for reverse logistics performance evaluation. Design/methodology/approach The performance measures, based on triple bottom line approach, were selected, and fuzzy analytical hierarchy process and extent analysis approach was applied for estimating the weights, global weights of performance measures and hence, the reverse logistics performance index. Reverse logistics performance of three electronic companies were evaluated and compared for the demonstration of the methodology. Findings The results show that economic performance has highest performance index followed by environmental performance and social performance. “Recapturing value” and “return on investment” from economic, “minimum energy consumption” and “optimum use of raw material” from environmental and “community complaints” and “customer health and safety” from social perspective have higher performance indexes. Over all, “reduced packaging”, “use of recycled material” and “employee benefits” show very poor performance indexes. Research Limitations/implications The study will provide useful guidance to the academicians and practitioners for evaluating, improving and benchmarking the reverse logistics performance. Originality/value The analysis adds to the very few studies on triple bottom line aspects of reverse logistics and its performance evaluation. Also, fuzzy analytical hierarchy process and extent analysis is used first time being an efficient tool to tackle the fuzziness of the data involved in performance evaluation.

Disposition decisions in reverse logistics by using AHP-fuzzy TOPSIS approach

Purpose The purpose of this paper is to explore the various disposition alternatives and to develop a framework for the optimal disposition decisions in reverse logistics. Design/methodology/approach In reverse logistics, once the products are collected and inspected, decision is to be taken regarding their disposition for reuse, re-manufacture or recycle or other possible alternatives. A combination of analytical hierarchy process (AHP) and fuzzy technique for order preference by similarity to ideal solution (TOPSIS) approach is proposed for the selection of best disposition alternative based on criteria economic benefits, environmental benefits, corporate social responsibility, stakeholder’s needs and reverse logistics resources. Findings A case of electronics firm was illustrated for the demonstration of the approach for the disposition of mobile phones. Returned mobile phones must be disposed for repairing or reuse in current business scenario, if possible. Otherwise, the firm may prefer to recycle them rather than dispose or remanufacture. Research limitations/implications The study is limited to mobile manufacturing firm. Also, these findings may vary depending on the sector and products. Further, empirical studies and case studies can be carried out to validate the findings. Practical implications The proposed framework provides useful tool to the practitioners and researchers in decision-making for disposition in reverse logistics. Originality/value Very few studies related to disposition decisions in reverse logistics were found in the previous research literature review. The study will add value to the very limited research on reverse logistics disposition. Also, the AHP-Fuzzy TOPSIS approach is first time being used for the disposition decisions in reverse logistics.

Computational fluid dynamics analysis of the production of bio-thermal spray hydroxyapatite powders

Hydroxyapatite (HA) thermal spray powder for hip implant’s coating may be produced via a mixed type spray drying technique. The HA thermal spray coating performance depends upon the quality of the starting HA powder. Production of this powder is based on a spray drying technique for its fast and continuous production since the HA slurry gets well dispersed in the drying medium through atomisation. This dispersal leads higher rate of evaporation per unit mass of HA product causing more extraction of water from the HA slurry. However, the quality of the powder produced by this spray drying method is low, with inconsistent morphologies and densities, properties that are required in the plasma deposition process. The objective of this study was to use the commercial CFD solver FLUENT to simulate the spray dryer so as to study the various controlling parameters in order to improve the quality of spray dried product. The simulation results predicted the particle size and thermal histories of powder as a result of changing the initial parameters such as HA slurry viscosity. Hence, it proved to be a useful method for understanding the dynamics of the spray drying technique and in optimising the spray drying process.

Optimum Machines Allocation in a Serial Production Line Using NSGA-II and TOPSIS

In the present scenario, manufacturing industries are witnessing large fluctuation in the product demands. The need of the hour is to have a responsive manufacturing system, which can cope up with these kinds of stochastic events. Reconfigurable Manufacturing System (RMS) is considered as modern manufacturing paradigm that offers customised functionality and capacity as and when required. The key enablers for this customisation in functionality and capacity are the Reconfigurable Machine Tools (RMTs) or simply Reconfigurable Machines (RMs). Selecting these multi-functionality and capacity machines along stations/stages of a product flow line is an important aspect for operating RMSs as it has direct implications on the operational performance of such system. In this paper, optimal configurations are selected under conflicting objectives based on cost, operation capability and reliability of the machines. The objective is to assign those machine configurations that minimises the cost while maximising the operation and reliability of the production line. The problem is framed as a multi-objective optimisation problem and is solved using NSGA-II. The results so obtained are discussed in terms of the performance of the reconfigurable system.

Synthesis and effect of Misch metal on mechanical properties of conventional cast Mg–Al–Zn–Sn–Pb alloy system

Magnesium alloys are increasingly accepted in automobile industry owing to their greater strength-to-weight ratio. These qualities lead to less vehicle weight and better fuel economy. Therefore, in the present work an effort has been made to develop a new Mg alloy system that exhibits greater ductility together with greater mechanical strength. Misch metal is added in Mg-based alloys to investigate the changes in mechanical properties. The microstructure of alloys Mg–4Al–3Zn–3Sn–3Pb (H1) and Mg–4Al–3Zn–3Sn–3Pb–0.5MM (H2) are dendritic in nature while for Mg–3Zn–3Sn–3Pb–2Si (H3) the “Chinese script” Mg2Si intermetallic structure was obtained. The ultimate tensile strength and elongation of Mg–4Al–3Zn–3Sn–3Pb–0.5MM (H2) alloy are about 40% and 100 % higher than that of H3 alloy. The ultimate tensile strength, yield strength, and percentage elongation of H2 alloy are 170 MPa, 44 MPa, and 3.4%, respectively.

Study of dry wear behavior and morphological characteristic of 60%Mo-20%NiCr-10%CrC-10%Mo+Fe based alloy coating by atmospheric plasma spray technique

Abstract Efficiency and performance are two critical characteristics of the internal combustion engine. The power generating component is required to be efficient so as to increase the overall performance of the vehicle and to make maximum use of the energy. In this study, we investigate the effect of load and speed on the wear of plasma sprayed coating with 60% Mo and Fe, 20% Mo, 10% NiCr, 10% Mo on cast iron substrate were investigated. Cylinder liner material was used as the counter body. We analyzed wear behavior, wear mechanism, the coefficient of friction, and temperature variation with different load and speed on a pin on disc tribometer in a dry run condition for a constant run of 2500 m. The specific wear rate was found to be increasing with the increase of the load from 50 to 70 N. Simultaneously with the increase in sliding velocity, the coefficient of friction decreased from 0.4 to 0.3. Further, the microstructure of the coating was studied with the help of SEM, EDX, and X-ray diffraction.