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In Indian thermal power plants, the main cause of boiler tube failure is the presence of molten sulphates and vanadates, which deteriorate the tube material at high temperatures. To combat the hot corrosion failure of metals, thermal spray technology is adopted. This study aims to investigate and study the effect of hot corrosion behaviour of carbon nanotube (CNT)-reinforced ZrO₂-Y₂O₃ composite coatings on T-91 boiler tube steel in a molten salt environment at 900 °C for 50 cycles.

A plasma spray technique was used for development of the coatings. The samples were exposed to hot corrosion in a silicon tube furnace at 900 °C for 50 cycles. After testing, the test coupons were analysed by X-ray diffraction, scanning electron microscopy/energy dispersive spectroscopy and cross-sectional analysis techniques to aid understanding the kinetics of the corrosion reaction.

CNT-based reinforced coatings showed lower weight gain along with the formation of protective oxide scales during the experimentation. Improvement in protection against hot corrosion was observed with increase in CNT content in the coating matrix.

It is pertinent to mention here that the high temperature behaviour of CNT-reinforced ZrO₂-Y₂O₃ composite on T-91 steel at 900°C temperature in molten salt environment has never been studied. Thus, the present research was conducted to provide useful results for the application of CNT-reinforced composite coatings at elevated temperature.

The purpose of this study was to fabricate carbon nanotubes (CNT)-reinforced chromium oxide coatings and investigate mechanical and microstructural properties of these newly developed coatings on the boiler tube steel.

1 and 4 Wt.% CNT-reinforced Cr₂O₃ composite coatings were prepared and successfully deposited on ASTM-SA213-T22 (T22) boiler tube steel substrates using high-velocity oxy fuel (HVOF) thermal spraying method. Microhardness, porosity, metallography, X-ray diffraction (XRD), scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy, cross-sectional elemental analysis and X-ray mapping analysis have been used to examine the coated specimens.

The porosity of the CNT-Cr₂O₃ composite coatings was found to be decreasing with the increases in CNT content, and hardness has been found to be increasing with increase in percentage of CNT in the composite coatings. The CNT were able to increase hardness by approximately 17 per cent. It was found that the CNT were uniformly distributed throughout Cr₂O₃ matrix. The CNT were found to be chemically inert during the spraying process.

It must be mentioned here that studies related to fabrication of HVOF sprayed CNT reinforced Cr₂O₃ composite coatings on T22 boiler tube steel are not available in the literature. Hence, present investigation can provide valuable information related to fabrication and properties of CNT reinforced coatings on boiler steel.

The main cause of boiler tube failure in high-temperature thermal power plants is molten sulphate-vanadate-induced hot corrosion. Applying thermal spray coatings on alloy steels can reduce hot corrosion. This study aims to examine the impact of nano yttria stabilized zirconia (YSZ) reinforcement on Ni-20Cr composite coatings on hot corrosion behaviour of T22 steel in a corrosive environment of Na₂SO₄-60%V₂O₅ at 650 °C over 50 cycles.

The coatings were deposited using a high velocity oxyfuel technique. The samples were subjected to hot corrosion in a Silicon tube furnace at 650 °C for 50 cycles. Weight gain data after each cycle were used to analyse the kinetics of corrosion behaviour. Corrosion products were examined using X-ray diffraction, scanning electron microscopy, energy dispersive and cross-sectional analytical methods.

During investigation, nano YSZ-reinforced Ni-20Cr composite coatings on T22 steel were discovered to give superior corrosion resistance in a molten salt environment at 650 °C. Throughout the experiment, the coatings gained less weight and formed protective oxide scales. Increased YSZ concentration in the coating matrix resulted in better protection against hot corrosion.

The inclusion of nano YSZ reduced porosity in Ni-20Cr coatings by filling voids and interlocking particles, as well as blocking the penetration of corroding species, hence improving the corrosion resistance of composite coatings. The corrosion rate decreased with increasing YSZ content in the coating matrix.

It should be noted that the high temperature corrosion behaviour of thermally sprayed nano YSZ-Ni-20Cr composite coatings has never been investigated and is not documented in the literature. As a result, the current study can provide useful information for the application of nano YSZ-reinforced coatings in high-temperature fuel combustion conditions.

Molten sulphate-vanadate induced hot corrosion is the main reason of failure of boiler tubes used at high temperatures in thermal power plants. The hot corrosion can be encountered by applying thermal spray coatings on the alloy steels. In this perspective, this paper aims to attempt to investigate the effect of carbon nanotubes reinforcement on Cr₂O₃ composite coatings on hot corrosion behaviour of ASTM-SA213-T22 steel in a corrosive environment of Na₂SO₄ – 60%V₂O₅ at 900^°C for 50 cycles.

The coatings have been deposited with high velocity oxy fuel process. The samples were exposed to hot corrosion in a Silicon tube furnace at 900^°C for 50 cycles. The kinetics of corrosion behaviour were analysed by the weight gain measurements after each cycle. Corrosion products were analysed with X-ray diffraction, scanning electron microscopy, energy dispersive and cross-sectional analysis techniques.

During investigations, the carbon nanotubes (CNT) reinforced Cr₂O₃ composite coatings on T22 steel were found to provide better corrosion resistance in the molten salt environment at 900^°C. The coatings showed lower weight gain along with formation of protective oxide scales during the experiment. Improvement in protection against hot corrosion was observed with increase in CNT content in the coating matrix.

The addition of CNT has resulted in reduction in porosity by filling the voids in chromium oxide coating, with interlocking of particle and has blocked the penetration of corroding species to enhance the corrosion resistance of the composite coatings. The corrosion rate was found to be decreasing with increase in CNT content in coating matrix.

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

The airline passenger industry in India was a mess in 2013, but the low-cost carrier IndiGo was making money. This relatively new company had managed to work against the odds and grab market share from longer-established flyers. Still, the weak rupee, depreciated by 15%, was sending a chill wind through the aviation sector, and growth plans would have to include opening new destinations. This meant hiring more employees, opening more ticketing stations, and increasing costs. Could the airline continue its climb, or would it be prudent to prepare for a hard landing?

Discussion of the case will enable the students to: ● use “Strengths, Weaknesses, Opportunities, and Threats” analysis. ● Use “pros and cons” analysis. ● Explain what constitutes an effective strategy. ● Analyze the quality of the strategy for IndiGo Airlines (IA). ● Explain sustained competitive advantage through value, rareness, imitability and organization framework.

This case describes a situation in which InterGlobe Aviation Ltd. (IGAL) has been experiencing multiple engine snags because of the faulty Pratt and Whitney engines. In a span of two years between June 2018 and January 2020, IGAL faced around 22 snags. IGAL is known to be one of the safest airlines in the world, the engine issue has tainted its reputation. In October 2019, in just one week IA faced four-engine snags, forcing the Directorate General of Civil Aviation (DGCA) to come out with a guideline in November 2019. The faulty engines were to be replaced by January 31, 2020. If IA failed to complete the task by the given deadline then IA would have to ground around 70–80 aircraft. IA was way behind the deadline when on January 13, 2020, they received an email from DGCA mentioning an extension of the deadline to May 31, 2020. The purpose of this case is to provide an opportunity for the participants to take into consideration the data given for IA and make assumptions and resolve the dilemma through which Ronojoy Dutta (Dutta), the Chief executive officer if IA is going through.

The case engages the participants in deciding a suitable course of action for IA to develop a strategy and is ideal to teach elements of strategy. The case can be used in the following courses/programs: ● A strategy formulation module in strategic management program or post-graduate program in management.

Teaching Notes are available for educators only.

CSS 11: Strategy.

Teaching Notes are available for educators only.

The AirAsia India 2017 (AAI) case presents the situation faced by Tony Fernandes, the CEO of the AirAsia group of companies, in 2017, when he had to respond to the changes in aviation policy made by the Ministry of Civil Aviation (MCA). As per the changes, an airline operating in India could start its international operations without having five years of domestic flying experience provided it deployed 20 of its aircraft or 20% of the total capacity, whichever was higher, for domestic operations. The objective of this case is to help discuss issues relating to sustaining late entry and exploring new growth opportunities in the context of regulatory changes.

This paper aims to identify various macroeconomic variables that affect the stock market performance of developed and emerging economies. It also investigates the effect of these factors on the stock markets of both economies. The impact of these variables on broad market indices and sectoral indices is investigated and compared too.

The publications for the study were retrieved from databases such as Emerald Insight, EBSCO, ScienceDirect and JSTOR using the keywords “Macroeconomic variables” and “Stock market” or “Stock market performance.” The result demonstrated a growing corpus of scholarly work in the domain of stock market. The study was carried out separately for each macroeconomic indicator. Given a large number of articles under consideration, the authors began by reading the titles and abstracts of all publications to identify those that were relevant. The papers are evaluated in Excel and the articles for review range from 1972 to 2021.

The authors found that gross domestic product (GDP), FDI (Foreign Direct Investment) and FII (Foreign Institutional Investment) have a positive effect on both emerging and developed economies’ stock market while gold price has a negative effect. Interest rates had a negative impact on both economies except for a few developing countries. The relationship with oil prices was positive for oil exporting countries while negative for oil importing countries. Inflation, money supply and GDP are the macroeconomic variables that have the same effect on sectoral indices as they do on broad market indices. The impact was sector-specific for the remaining variables.

This paper gives an overview of relation and effect covering variety of macroeconomic variables and stock market indices. Still, there is a scope for further research to analyze the effect on thematic, strategy and sectoral indices. A longer time horizon with new variables, such as bank deposit growth rate, nonperforming assets of banks, consumer confidence index and investor sentiment, can be studied using high-frequency data. This research may help stakeholders adopt and manage their policies during a crisis or economic slump.

This study will assist investors, researchers and educators in the fields of economics and finance in understanding how macroeconomic factors affect the stock market. Furthermore, this study can guide in portfolio diversification strategy across multiple sectors by examining the impact of macroeconomic factors specific to sectoral indices. This paper provides insight into society and researchers since it integrates a number of macroeconomic variables and their interaction with the stock market. It may also help pension funds and mutual fund firms to hedge their funds and allocate equity portfolios.

With respect to India, this study looked at new macroeconomic variables and sectors. It contrasted the impact of these variables in developed and developing economies. The effect of broad and sectoral stock indexes was also investigated and compared. The authors examined how these variables responded during crisis and economic downturns by using articles from a longer time frame. This research also looked into how changing the frequency of data for the variables altered stock performance. This paper emphasized the need for more research into thematic, strategy and broad market indices, such as small-cap and mid-cap indices.

This paper aims to investigate hot corrosion behaviour of different Cr₃C₂–NiCr coatings on boiler tube steel.

High velocity oxy fuel technique has been used to deposit different coatings on commercially available ASTM-SA213-T22 boiler tube steel. The hot corrosion studies have been performed in molten salt environment at 900°C temperature in silicon tube furnace in laboratory.

The results showed that uncoated superalloy suffered intense spalling and the weight change was massive during each cycle on studies of hot corrosion 900°C. The 100 per cent NiCr and 10 per cent (Cr₃C₂) – 90 per cent (NiCr) coatings provided better protection to T22 steel against the hot corrosion because of the formation of Ni and Cr₃C₂ layers.

In this research a variety of coatings have been used. This research work has been aimed to investigate the hot corrosion behavior of Boiler Steel b with different Cr₃C₂–NiCr coatings, under molten salt environment in Silicon tube furnace at 900°C, under cyclic conditions.

This study aims to explore the interrelationships among human-related lean practices, lean production shop floors, process quality, inventory management, operational productivity and business productivity.

This study used a cross-sectional survey approach, and quantitative data were collected from 324 Indian auto-component manufacturing firms. Confirmatory factor analysis was used, followed by structural equation modelling techniques for the conceptual model, which incorporated a complete set of 11 hypotheses.

The results confirmed that human-related lean practices trigger lean production shop floors and improve process quality. Furthermore, the study revealed the positive impact of a lean production shop floor on process quality and inventory management and the positive impact of process quality on both operational and business productivity. Finally, inventory management is of the utmost importance in achieving better operational and business productivity, and operational productivity positively leads to business productivity.

The findings of this study can benefit auto-component manufacturing firms by elucidating the complex relationships between human-related lean practices, lean production shop floors, process quality, inventory management, operational productivity and business productivity. Better knowledge of these relationships will enable firms to enhance efficiency levels, reduce costs and resource wastage and improve their overall performance. This study provides a good understanding of the interplay between lean and quality factors and their influence on inventory management and business performance.