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Epoxy zinc-rich coatings are widely used in harsh environments because of the long-lasting cathodic protection of steel surfaces. The purpose of this paper is to use flake zinc powder instead of the commonly used spherical zinc powder to reduce the zinc powder content.

In this paper, the authors have prepared an anticorrosive zinc-rich coating using a flake zinc powder instead of the conventional spherical zinc powder. The optimal dispersion of scaly zinc powder in zinc-rich coatings has been explored by looking at the surface and cross-sectional morphology and studying the cathodic protection time of the coating.

The final epoxy zinc-rich coating with 35 Wt.% flake zinc powder content was prepared using sand-milling dispersions. It has a similar cathodic protection time and salt spray resistance as the 60 Wt.% spherical zinc-rich coating, with a higher low-frequency impedance modulus value.

This study uses flake zinc powder instead of the traditional spherical zinc powder. This reduces the amount of zinc powder in the coating and improves the corrosion resistance of the coating.

The main operations of the powder-coating process are staggered along a closed-loop conveyor. Given the volatile market demands, using a fixed level of staffing may result in significant productivity losses. The present study aims to capture stochastic behavior and optimize operator assignment problems in a practical powder-coating process. By using the proposed methodology, when demand changes, the optimal operator assignment configuration can be provided, ensuring high labor productivity.

The powder-coating process is an important industrial application and is often a labor-intensive system. The present study adopts a practical case to optimize its staffing level. Because of its operational complexity, the problem is solved by a proposed simulation-optimization approach. The results are promising, and the proposed methodology is shown to be an effective approach.

The proposed methodology was tested for various demand levels. The optimized operator assignment configuration always improves on the performance of other staffing levels. Given the same daily throughput, the optimized operator assignment configuration can improve performance by as much as 19%. In scenarios where there is increased demand, the resulting reduction in overtime work improves performance by between 20.33% and 56.72%. In scenarios where there is reduced demand, the optimized staffing level produces improvements between 3.13% and 50%. Compared with the fixed staffing policy of the case company, the flexible staffing policy of the proposed methodology can maintain high labor productivity across demand variations. The results are consistent with the Shojinka philosophy of the Toyota Production System.

This study proposes a solution to the operator assignment decision in a labor-intensive manufacturing system – a powder-coating processing system. Powder coating provides a solid powder coating without any solvent. Because of its excellent application performance and environmental protection, it is widely used in the field of metal coating, especially appliances for offices and homes. Most of the existing literature has solved the problem by making unrealistic assumptions. The present study proposes a simulation-optimization method to solve a practical problem in powder-coating processing. The effectiveness of the proposed methodology is illustrated by a practical application. According to the experimental results, five operators can be saved for the same daily throughput. An average of 35 and 19 min of overtimes can be saved when demand increases by 10% and 20% with one less operator; between 2 and 16 operators can be saved when demand falls by 10%–60%.

The purpose of this study is to evaluate the effect of graphene, basalt flakes and their synergy on the corrosion resistance of zinc-rich coatings. As the important heavy-duty anticorrosion coatings, zinc-rich coatings provided cathodic protection for the substrate. However, to ensure cathodic protection, a large number of zinc powder made the penetration resistance known as the weakness of zinc-rich coatings. Therefore, graphene and basalt flakes were introduced into zinc-rich coatings to coordinate its cathodic protection and shielding performance.

Three kinds of coatings were prepared; they were graphene modified zinc-rich coatings, basalt flakes modified zinc-rich coatings and graphene-basalt flakes modified zinc-rich coatings. The anticorrosion behavior of painted steel was studied by using the electrochemical impedance spectroscopy (EIS) technique in chloride solutions. The equivalent circuit methods were used for EIS analysis to obtain the electrode process structure of the coated steel system. Simultaneously, the corrosion resistance of the three coatings was evaluated by water resistance test, salt water resistance test and salt spray test.

The study found that the addition of a small amount of graphene and basalt flakes significantly improved the anticorrosion performance of coatings by enhancing their shielding ability against corrosive media and increasing the resistance of the electrochemical reaction. The modified coatings exhibited higher water resistance, salt water resistance and salt spray resistance. The graphene-basalt flakes modified zinc-rich coatings demonstrated the best anticorrosion effect. The presence of basalt scales and graphene oxide in the coatings significantly reduced the water content and slowed down the water penetration rate in the coatings, thus prolonging the coating life and improving anticorrosion effects. The modification of zinc-rich coatings with graphene and basalt flakes improved the utilization rate of zinc powder and the shielding property of coatings against corrosive media, thus strengthening the protective effect on steel structures and prolonging the service life of anticorrosion coatings.

The significance of developing graphene-basalt flakes modified zinc-rich coatings lies in their potential to offer superior performance in corrosive environments, leading to prolonged service life of metallic structures, reduced maintenance costs and a safer working environment. Furthermore, such coatings can be used in various industrial applications, including bridges, pipelines and offshore structures, among others.

The purpose of this paper is to develop a physical model able to predict the shape of the capillarity effect in multi-jet fusion when two facing edges mutually affect each other. The work also aims at testing the consistency of such a model with experimental observations.

An analytical model of the phenomenon is developed considering the surface tension of the polymer melt adhering to the unfused powder. The general equilibrium equations are solved by imposing the boundary conditions corresponding to the case of two close facing edges, in which the shapes of the menisci are mutually influenced. The analytical model is validated through an experimental activity. Specifically, a set of parallelepipeds with variable width was manufactured using an HP Multi Jet Fusion 4200. The morphologies of capillarities were captured via three-dimensional scanning and compared with those predicted by the model.

The results of this study demonstrate that the average error to the experimental capillarity profile is lower than that obtained by existing methods. Particularly, considerable improvements are achieved as far as the maximum capillarity height is concerned. The manufactured specimens exhibit a change in slope near the edges, which is arguably attributable to coating powder and other effects not included in the analytical model.

The model presented in this study differs in hypotheses from previous methods in literature by assuming a null derivative of the capillarity shape in the central point of the meniscus. This allows for a more accurate prediction of the defect morphology in the case of close facing edges.

This paper aims to investigate the high temperature corrosion behaviour of ZrO₂-reinforced Cr₂O₃ matrix-based composite coatings on ASTM-SA213-T-22 steel at 900°C in molten salt environment. The different coatings were deposited by high velocity oxy fuel (HVOF) method.

Hot corrosion studies were conducted in simulated boiler environment in silicon carbide tube furnace at 900°C for 50 cycles on bare and HVOF-coated boiler steel specimens. Each cycle consisted 50 h of heating in the simulated boiler environment followed by 20 min of cooling in air. The weight change measurements were performed after each cycle to establish the kinetics of corrosion using thermogravimetric technique. X-ray diffraction and scanning electron microscopy techniques were used to analyse the corroded specimens.

The addition of 20 Wt.% ZrO₂ in Cr₂O₃ helped reduce corrosion rate by 89.25% as compared to that of uncoated specimen. The phase analysis revealed the presence of Cr₂O₃ and ZrO₂ phases in composite coating matrix, which may have prevented the base metal from interacting with the corrosive elements present in the highly aggressive environment and thus had increased the resistance to hot corrosion.

It should be mentioned here that high temperature corrosion behaviour of thermally sprayed ZrO₂–Cr₂O₃ composite coatings has never been studied, and to the best of the authors’ knowledge, it is not available in the literature. Hence, present investigation can provide valuable information for application of ZrO₂-reinforced coatings in high temperature fuel combustion environments.

Most of the industrial buildings which are designed to moderate loads are constructed using light gauge cold-formed steel (CFS) sections. Residual mechanical properties of CFS sections exposed to elevated temperature need to be investigated as it is necessary to predict the deterioration of elements to avoid failure of the structure or its elements. Also, it would be helpful to decide whether the structural elements need to be replaced or reused. The use of fire-resistant coatings in steel structures significantly reduces the cost of repairing structural elements and also the probability of collapse. This study investigates the effect of fire-resistant coating on post-fire residual mechanical properties of E350 steel grade.

In this study, an attempt has been made to evaluate the residual mechanical properties of E350 steel. A tensile coupon test was performed for the extracted specimens from the exposed CFS section to determine the mechanical properties. Four different fire-resistant coatings were selected and the sections were coated and heated as per ISO 834 fire temperature curve in the transient state for time durations of 30 minutes (821°C), 60 minutes (925°C), 90 minutes (986°C), and 120 minutes (1,029°C). After the exposure, all the coupon specimens were cooled by either ambient conditions (natural air) or water spraying before conducting the tension test on these specimens.

At 30 min exposure, the reduction in yield and ultimate strength of heated specimens was about 20 and 25% for air and water-cooled specimens compared with reference specimens. Specimens coated with vermiculite and perlite exhibited higher residual mechanical property up to 60 minutes than other coated specimens for both cooling conditions. Generally, water-cooled specimens had shown higher strength loss than air-cooled specimens. Specimens coated with vermiculite and perlite showed an excellent performance than other specimens coated with zinc and gypsum for all heating durations.

As CFS structures are widely used in construction practices, it is crucial to study the mechanical properties of CFS under post-fire conditions. This investigation provides detailed information about the physical and mechanical characteristics of E350 steel coated with different types of fire protection materials after exposure to elevated temperatures. An attempt has been made to improve the residual properties of CFS using the appropriate coatings. The outcome of the present study may enable the practicing engineers to select the appropriate coating for protecting and enhancing the service life of CFS structures under extreme fire conditions.

Sai Coating, a small entrepreneurial firm, was one of the three firms that had received the license from ARCI for marketing the Detonation Spray Coating (DSC). Sai Coating made and sold the detonation gun (D-Gun) to three sectors, namely: Wire Drawing, Textiles and Aero components. The coating enhanced the life of the coated wire or surface and its functionality in some ways. The firm had a turnover of INR 4,500,000 and was looking to generate scale and maximize its revenues. The case revolves around the pricing strategy to be adopted by Sai coating to extract value from different set of customers. What should be the price levels given the nature of the product?

This study aims to focus on how reactive diluents with mono- and di-functionalities affect the properties of resin formulation developed from bioderived precursors. A hydroxyethyl methacrylate (HEMA) terminated urethane acrylate oligomer was synthesized and characterized to study its application in stereolithography 3D printing with different ratios of isobornyl acrylate and hexanediol diacrylate.

Polyester polyol was synthesized from suberic acid and butanediol. Additionally, isophorone diisocyanate, polyester polyol and HEMA were used to create urethane acrylate oligomer. Fourier transform infrared spectroscopy and ¹H NMR were used to characterize the polyester polyol and oligomer. Various formulations were created by combining oligomer with reactive diluents in concentrations ranging from 0% to 30% by weight and curing with ultraviolet (UV) radiation. The cured coatings and 3D printed specimens were then evaluated for their properties.

The findings revealed an improvement in thermal stability, contact angle value, tensile strength and surface properties of the product which indicated its suitability for use as a 3D printing material.

This study discusses how oligomers that have been cured by UV radiation with mono- and difunctional reactive diluents give excellent coating characteristics and demonstrate suitability and stability for 3D printing applications.

This case study will allow students to understand and analyse the process for conducting equity valuation by building a three-statement financial model, to understand and apply the workings of discounted cash flow (DCF) valuation methodology and its components, to apply the concepts related to the calculation of the weighted average cost of capital in the determination of discounting rate, to understand the terminal value calculation and assumptions thereof and to analyse the intrinsic valuation for the target company using the traditional multi-stage DCF model for investment decision-making.

In July 2019, Kapil Agarwal, an equity analyst operating out of Mumbai, India, was carefully looking over the financials of Asian Paints, a leading paints company in India. As an equity analyst, Kapil was constantly on the lookout for fundamentally strong but undervalued companies that could create long-term wealth for his equity fund. To decide upon the right valuation of Asian Paints, Kapil conducted fundamental analysis using the DCF method on the basis of available financial information. This case study puts students in an investment analyst role wherein they forecast financial statements and conduct DCF valuation for Asian Paints to discover potentially undervalued stocks for investment decision-making.

This case study is designed for use in an undergraduate or postgraduate programme in business management, particularly in a course on business valuation or investment management or security analysis.

Teaching notes are available for educators only.

CSS 1: Accounting and Finance.

The case has the following learning objectives: to understand the dilemmas that an emerging market MNC faces during pre-and post-acquisition scenarios; understand and appreciate the basic tensions that arise when two different companies with different cultural setups are integrated; understand the importance of creating a culture integration road map to leverage the synergies of two successful companies; and understand the role of leadership in leading and managing change.

Asian Paints Ltd. has been a market leader in the Indian paint market for over five decades (since 1967). Over the years, starting in 1978, the company has steadily spread its footprint in the international arena as well. As of 2017, Asian Paints was a leader in 10 overseas markets, one of the top 3 paint companies in the Middle East, the largest paint manufacturing company in South Asia, and served 60 markets across the world. The international business contributed to around 12% of the company’s group turnover. In line with its long-term vision and to consolidate its presence in emerging markets, the company acquired Causeway Paints, a leading paint company in Sri Lanka, in April 2017. Asian Paints had a presence in Sri Lanka since 1999. Mr. Jatin Upadhyay, International Business Unit Head for Asian Paints, had played significant roles in the past in such acquisitions and was well aware of the impending challenges that came with such acquisitions. How would the integration of the two distinct entities be made possible without losing the overarching objective? How would the transition be managed? How would the cultural transition take place? What and how would the role be handled by the General Manager (GM) of Causeway Lanka? How would the new organisational structure support the transition? The case illustrates the complex management challenges that arise when a leading enterprise from a different country (Asian Paints) acquires a leading company in a different country, in this case, Causeway Paints, Sri Lanka.

The target audience for this case study is the students pursuing a post-graduate programme in management or an executive post-graduate programme in management. The case can also be used for management development programmes for experienced participants who are interested in understanding the possible scenarios that may arise after an acquisition when managing an international subsidiary in a different cultural setting.

Teaching notes are available for educators only.

CSS 6: Human Resource Management.