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Stir casting is a promising technique used for the manufacture of Al-SiC metal matrix composites. The clustering of reinforcement particles is a serious concern in this production method. In this work, mushy-state solidification characteristics in stir casting are numerically simulated using computational fluid dynamics techniques to study the clustering of reinforcement particles.

Effects of process parameters on the distribution of particles are examined by varying stirrer speed, volume fraction of reinforcement, number of blades on stirrer and diameter ratio (ratio of crucible diameter to stirrer diameter). Further, investigation of characteristics of cooling curves during solidification process is carried out. Volume of fluid method in conjunction with a solidification model is used to simulate the multi-phase fluid flow during the mushy-state solidification. Solidification patterns thus obtained clearly indicate a strong influence of process parameters on the distribution of reinforcement particles and solidification time.

From the simulation study, it is observed that increase in stirrer speed from 50 to 150 rad/s promotes faster solidification rate. But, beyond 100 rad/s, stirrer speed limit, clustering of reinforcement particles is observed. The clustering of reinforcement particles is seen when volume fraction of reinforcement is increased beyond 10 per cent. When number of blades on stirrer are increased from three to five, an increase in solidification rate is observed, and an uneven distribution of reinforcement particles are observed for five-blade geometry. It is also seen from the simulation study that a four-blade stirrer gives a better distribution of reinforcement in the molten metal. Decrease in diameter ratio from 2.5 to 1.5 promotes faster solidification rate.

There is 90 per cent closeness in results for simulation study and the published experimental results.

In hot forging, a significant amount of forging force is used for overcoming frictional force at the die-billet interface. The high frictional force along with thermomechanical stress lead to wear, plastic deformation, mechanical fatigue and cracks, which reduce the service life of hot forging dies. Of all these different types of issues, wear is the predominant mode of failure in hot forging dies. This paper aims to describe mechanisms of wear transition in different loads at near forging temperature, occurring during sliding of chromium-based H11 tool steel specimens.

High temperature pin-on-disc tests are performed with pin specimens machined from bars of X38CrMoV5 steel, heat treated to surface hardness of 40-42 HRc. The disc is made of EN 31 steel with hardness of 60-62 HRc. Tests are performed at constant temperature of 500°C, and the normal load was varied from 20 to 70 N.

Scanning electron microscopy investigations on worn surface have revealed that wear is primarily due to abrasion and plastic deformation. The test results show an increasing trend in wear rate with increase in load up to 30 N, followed by a reversal in trend until 50 N. This transition in wear rate is caused by development of wear resistant layers, which are formed by compaction of wear debris particles on to the worn surfaces. These compact layers are found to be stable during load range from 40 and 50 N. However, with further increase in load, abrasive wear tracks are observed without any evidence of protective layers. As a result, there is an increase in wear rate with increase in loads above 50 N. In addition, plastic shearing was dominant over abrasive wear at this load regime.

The study on wear behaviour of H11 hot forging steel at 20 to 70 N will be an input to the research in hot forming industries.

The prime task of research in hot forging industry is to improve the service life of forging dies. The in-service microstructural changes that may occur in a die during hot forging is expected to significantly affect the service life. The purpose of this work is to analyse the microstructural evolution of double tempered hot forging dies in a real industrial environment, and the correlation of microstructural and microhardness evolution to the in-service wear and plastic deformation.

Specific hot forging tests were carried out on double tempered AISI H11 chromium tool steel for 100, 500 and 1,000 forging strokes. Macro analysis was conducted on die cross section to analyse the wear and plastic deformation at different stages of forging cycles. Microhardness and microstructural analyses were performed on the die surface after these forging tests.

The macro analysis on the transverse section of dies shows that wear is predominant during initial forging strokes, whereas plastic deformation is observed in later stages. Microstructural analyses demonstrate that during first 500 forging cycles, carbide population decreases at 63 per cent higher rate as compared to corresponding drop during 501 to 1,000 forging cycles. Additionally, the carbide size increases at all stages of forging cycle. Further, microstructural images from dies after 1,000 forging strokes show clustering and spherodisation of carbides by which the “blocky”-shaped carbides in pre-forging samples had spherodised to form “elongated spherical” structures.

The findings of this work can be used in hot forging industries to predict amount of wear and plastic deformation at different stages of service. From the results of this work, the service life of double tempered H11 hot forging dies used in forging without lubrication is within 501 to 1,000 forgings.

Most of the literatures are focussed on the cyclic softening of material at constant temperature. This work analyses the microstructural evolution of double tempered hot forging dies in a real industrial environment and correlates the microstructural and microhardness evolution to the in-service wear and plastic deformation.

This paper gives a bibliographical review of the finite element modelling and simulation of indentation testing from the theoretical as well as practical points of view. The bibliography lists references to papers, conference proceedings and theses/dissertations that were published between 1990 and 2002. At the end of this paper, 509 references are listed dealing with subjects such as, fundamental relations and modelling in indentation testing, identification of mechanical properties for specific materials, fracture mechanics problems in indentation, scaling relationship for indentation, indenter geometry and indentation testing.

The purpose of this paper is to evaluate the influence of temperature, load and sliding speed on wear and friction behavior of LM25/SiC composites in as-cast and heat-treated conditions.

The LM25/SiC aluminum matrix composites (AMCs) were prepared using the stir casting process. The wear tests were carried out using a pin-on-disc setup in dry condition. The three levels of each parameter, i.e. 100, 150 and 200°C operating temperature; 15, 25 and 35 N load; 0.8, 1.6 and 2.4 m/sec sliding speed, were considered for the investigation. ANOVA has been carried out to evaluate the percentage contribution of parameters. Scanning electron microscope analysis of worn surfaces has been carried out to understand the wear mechanism.

The wear and coefficient of friction (COF) increase with the increase in the temperature, load and sliding speed within a selected range for as-cast as well as heat-treated LM25/SiC AMCs. The mean values of wear and COF in heat-treated samples were found to be lower than as-cast samples for all cases. It was observed that the percentage wear increases significantly as temperature increases in as-cast AMCS. Mild to severe wear transition was observed at 150°C. In heat-treated AMCs, mild wear was observed irrespective of temperature. It was also observed that as the temperature increases, transition of wear mechanism from abrasive to adhesive (including delamination) occurs earlier in as-cast samples as compared to heat-treated samples.

There is a lack of data on combined effect of temperature, load and sliding speed on tribological aspects of as-cast and heat-treated LM25/SiC AMCs, limiting its applications. The present research work has addressed this gap.

This study aims to experimentally investigate branded functional beverage (BFB) consumption behaviour post-COVID-19 through the lens of a conceptual framework built on three renowned behaviour modification models and to critically evaluate how well subjective norms serve as a moderator in the consumption behaviour relating to such beverage products.

A conceptual model was developed based on the tenets of the theory of planned behaviour (TPB), health belief model (HBM) and value-attitude-behaviour (VAB) model. The study was performed on a convenience sample of 537 respondents aged 18 and up from diverse regions in India using the PLS-SEM method. A total of 444 useable questionnaires were utilized for the final data analysis.

Given the post-pandemic setting, the perceived benefits of BFBs significantly influenced its purchase intention and consumption behaviour. It could grossly impact the media's role (information about COVID-19) and the consumers' interest in healthy food. The study revealed that the information about COVID-19 (role of media) strongly increased interest in healthy food, whereas interest in healthy food positively influenced purchase intention of functional beverages. With interest in healthy food as a “mediator”, the role of media (information about COVID-19) positively influenced purchase intention. It is worth noting the moderating role of subjective norms in the relationship between the role of media (information about COVID-19) and interest in healthy food and that between interest in healthy food and BFB purchase intention.

Food marketers shall skillfully use “opinion” leaders and subject experts in marketing communication campaigns to popularize the link between good food and immunity through COVID-19 and healthy diet-related messages sent via a suitable media platform. This would grab food consumers' interest in BFBs and persuade them to incorporate such items in their daily food milieu. Consumers need to be assured that consuming “functional” products would deliver health benefits and upkeep their body immunity in the post-COVID-19 times.

There has been minimal research on the link between perceived benefits, the role of media, interest in healthy food and consumption behaviour on functional beverages in the post-COVID-19 setting. Moreover, subjective norms have never been probed as a moderator in the consumer behaviour studies on BFBs. This pioneering study applied the tenets of the TPB, HBM and VAB model in the context of post-pandemic functional beverage consumption. The altered study settings caused by the COVID-19 pandemic and the context of a developing economy like India have amplified the research value of this study.

This conceptual paper aims to study the Corona Virus Disease-19 (COVID-19) pandemic’s impact on branded functional beverages consumption in India. There is a sincere effort to critically review the role of some vital determinants of consumer behaviour and to develop an integrated model for branded functional beverages consumption behaviour.

A systematic and extensive literature review was performed by searching electronic databases relating to consumer acceptance and purchase behaviour of functional beverages in India from 2000 to 2021. This study also reviewed very recent literature on the potential impact of the COVID-19 pandemic on global consumer traits, buying behaviour, marketing trends and psychographic behaviour.

The extensive review of the literature yielded results that shed light on some crucial factors propelling branded functional beverages’ consumption behaviour in India, especially in the COVID-19 scenario.

The study is based purely on a conceptual understanding of branded functional beverages’ consumption behaviour among Indian consumers. The conceptual framework proposed here results from the review of past literature. Therefore, the scientific world is invigorated to test further the implications presented in this study empirically.

The conceptual framework proposed here concerning consumer behaviour in functional beverages would guide the food marketers to segment and position their functional food offerings, mainly beverage variants, in the post-pandemic scenario. Moreover, the study findings enable policymakers to craft food policies to uphold the noble cause of moulding a healthy generation.

The COVID-19 pandemic has virtually shattered our food system and modified our associations with food in many different ways. The perception of health risks associated with COVID-19 might have influenced people’s food purchase and consumption behaviours. It is proposed that health-conscious people would prefer more health-promoting foods and beverages to strengthen their immunity. Several reports disclose that food consumers in India demand functional foods and beverages more extensively than before to include in their daily food basket. A detailed literature review revealed an evident shortage of research studies regarding consumer behaviour in functional beverages in India. No prior research works could be identified as to why consumers prefer functional beverages to benefit their overall health and immunity and what guides them to purchase or not to purchase such products, especially in the post-pandemic scenario. Therefore, this research work would be a primer that would guide future studies investigating consumers’ attitudes and purchasing behaviour of branded functional beverages.

The purpose of this study is to identify the cricketers who were able to justify their salary by their on‐field performance in the Indian Premier League (IPL).

A measure is developed to quantify the batting, bowling and wicket keeping performance of a cricketer into one single index called as the performance index. Based on the performance index of cricketers, from first three seasons of IPL, and using the binomial option pricing model, the neutral present values of the cricketers are determined. The distributional pattern of the present values of cricketers is identified and cricketers are classified based on the level of present values. Similarly, the distributional pattern of the bid prices of cricketers is identified and the cricketers are classified on the level of their bid prices. The cross tabulation of the classified bid prices and classified present values, can be used to identify the cricketers who were able to justify their salaries.

The study can spell out which players had amplified their bid prices and to what extent by their on‐field performances.

The performance measure developed in the paper does not consider the fielding skill of the cricketers, as there is no established measure for fielding performance in the game of cricket. Another limitation of the study is that the risk neutral probabilities for the upward and downward states, for the different time periods are assumed to be constant. However, in real life situations these risk neutral probabilities may not be constant for the different time periods.

The proposed model of performance measurement can also be used in several other professional sports. As the idea of IPL works, on franchisee‐system based of hiring players and transfers, so the same model can be applicable to all such sports like football, rugby, baseball where such system exists. This may be helpful to the franchisee to decide on which players should be considered and who should to be dropped for a given price. The players can also use this model to understand what their market price should be and ensure that they are not underpaid.

The article is the first of its kind and hence original in nature.

Online food delivery has been prevalent in recent years worldwide, especially during the COVID-19 pandemic, and people's consumption behaviors have changed significantly. This study aims to investigate the consumption behavior of young adults using online food delivery platforms during the COVID-19 pandemic and focuses on the dominant factors influencing their decision to use online food delivery platforms.

Semi-structured interviews including 14 young adults aged 18–25 living in Hong Kong were conducted to collect data about their perspectives on online food delivery platforms in five areas. This research adopted the stimulus-organism-response model (S-O-R model) to analyze how the factors influence young adult users' loyalty and satisfaction with online food delivery platforms.

Thematic analyses revealed that young adults were attracted to online food delivery platforms for their numerous benefits. They had a high frequency of usage and significant spending. Usability, usefulness, satisfaction and loyalty influenced young adults' behaviors on online food delivery platforms. Participants were overall satisfied with their experiences, but platforms still had room for improvement.

Few prior studies investigated the factors affecting the consumer experience and behavioral intention of online food delivery for young adults in Asia. This study contributes to understanding young adults' experiences and problems with online food delivery platforms. It provides practical insights for system engineers and designers to improve the current services and for the governments to enhance the existing regulatory loopholes.

High-quality labor supply is inevitable to maintain sustainable and steady economic growth. This study mainly explores the impact of the social pension system on the health of human capital, and further explores its impact mechanism.

On the basis of the data from China Family Panel Studies from 2012 to 2018, this article uses the fixed effect model and the mediation effect model to empirically study the influence of the social pension scheme on the health of human capital and further explore its influence mechanism.

This study shows that the social pension scheme can significantly improve the physical and mental health of laborers, especially for low-income and agricultural groups. The implementation of the social pension scheme contributes to increasing medical services and reducing the labor supply for the benefit of human health capital. Therefore, the government should continue to expand the coverage of the social pension scheme and comprehensively improve the importance of human health capital on economic growth.

Medical costs and labor supply play a mediating effect in the relationship between social pension and rural labors' health status, which indicates that medical costs and labor supply level are still important factors affecting the health status of rural labor. There are essential factors affecting the health status of the rural labor force, and their role should be given more consideration in the process of system design and improvement.

The existing studies have more frequently studied the effect of the implementation of social pension schemes from the perspective of economic performance, but this paper evaluates the policy effect of social pension schemes based on the perspective of health human capital, which enriches research on health performance in related fields.