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This study aims to evaluate the low energy impact characteristics of 3D printed carbon fiber thermoplastic and thermoset polymer composite using the Izod impact test. The effects of infill density are examined on the Izod impact properties of 3D printed thermoset polymer and thermoplastic composite specimens. Furthermore, a thorough investigation is conducted into the effect of heat treatment using a hot-air oven on both types of 3D printed composite specimens. To characterize the impact characteristics of each specimen, the fracture surfaces caused by impact load are inspected, and the fracture mechanism is studied using scanning electron micrographs.

Izod Impact specimens of thermoset (epoxy resin) and thermoplastic carbon fiber of different infill density (70, 75, 80, 85, 90 and 100%) are fabricated using the different fiber impregnation 3D printing process. To carry out the heat treatment process, printing of composites is done for each infill design from both thermoset and thermoplastic composites and the impact characteristics of specimens are evaluated on a pendulum test-rig using the ASTM D-256 standard. Using a scanning electron microscope, each fracture zone underwent four separate scanning processes, ranging in size from 2 µm to 100 µm.

The impact resistance of the 3D printed thermoset and thermoplastic composite material is significantly influenced by the type of fiber placement and infill density in the matrix substrate. Because of the weak interfacial strength between the layers of fiber and polyamide 6, the specimen printed with continuous fiber implanted at the part exhibited reduced impact resistance. At 75% infill density, the impact specimen printed with coextruded fiber showed the highest impact resistance with a 367.02% greater magnitude than the continuous fiber specimen with the same infill density.

This work presents a novel approach to analyze the low energy impact characteristics and three-dimensional printing of carbon fiber reinforced thermoplastic and carbon fiber reinforced thermoset and thermoplastic composite material.

The tensile behavior of additively manufactured nylon-based carbon fiber-reinforced composites (CFRP) is an important criterion in aerospace and automobile structural design. So, this study aims to evaluate and validate the tensile stiffness of printed CFRP composites (low- and high-volume fraction fiber) using the volume average stiffness (VAS) model in consonance with experimental results. In specific, the tensile characterization of printed laminate composites is studied under the influence of raster orientations and process-induced defects.

CFRP composite laminates of low- and high-volume fraction carbon fiber of different raster orientations (0°, ± 45° and 0/90°) were fabricated using the continuous fiber 3D printing technique, and tensile characteristics of laminates were done on a universal testing machine with the crosshead speed of 2 mm/min. The induced fracture surface of laminates due to tensile load was examined using the scanning electron microscopy technique.

The VAS model can predict the tensile stiffness of printed CFRP composites with different raster orientations at an average prediction error of 5.94% and 10.58% for low- and high-volume fiber fractions, respectively. The unidirectional CFRP laminate composite with a high-volume fraction (50%) of carbon fiber showed 50.79% more tensile stiffness and 63.12% more tensile strength than the low-volume fraction (26%) unidirectional composite. Fiber pullout, fiber fracture and ply delamination are the major failure appearances observed in fracture surfaces of laminates under tensile load using scanning electron microscopy.

This investigation demonstrates the novel methodology to study specific tensile characteristics of low- and high-volume fraction 3D printed CFRP composite.

Inconel 718 is used in gas turbine engines for aerospace applications due to high creep resistance but generating a hole with good surface integrity is challenging because the γ′′ interface is very strong so that slip is difficult in the grain boundary. So, the purpose of this work is to enhance the performance of drilling using a micro texture drill tool filled with solid lubricant.

Three different micro textures such as star shaped with 6-sharp apex, rectangular slots parallel and perpendicular to drill axis are created using laser on the drill tool. Deep cryogenic treatment is done on the textured tool to improve the strength and wear resistance before it is filled with solid lubricant. A detailed experimental investigation is performed to analyse the hole geometry and surface integrity of the drilled hole.

The accuracy of the drilled holes is enhanced in the star shaped texture drill tool over other textured and non-textured tools. A significant improvement in surface finish and hardness are observed and moreover cylindricity error, burr height of the hole is less for the above condition. It is also inferred that, at lower feed rate and higher speed produce hole with an accuracy of 96%.

Aerospace industry is focussing on improving the hole geometry and surface in Inconel 718. This work demonstrates the novel technique to improve drilling of Inconel 718 using laser textured tool filled by the solid lubricant.

The purpose of this paper is to analyse the effect of water absorption and heat treatment on the impact strength of three-dimensional (3D) printed Izod specimens. A low-cost post-processing technique is proposed to improve the impact strength of 3D printed parts substantially.

In the present work, the effect of water absorption and the heat-treatment on the impact resistance of 3D printed poly-lactic acid parts possessing different layer-height, build-orientation and raster-orientation was studied. Water absorption tests were conducted in distilled water and it was observed that the water- absorption in specimens follows the Fickian diffusion mechanism. A set of specimens was heat-treated at 120°C for 1 h using an induction furnace. Post water absorption and heat-treatment a significant increase in the impact resistance is noticed and especially a steep increase in impact resistance is observed in heat-treated specimens.

Experimental findings show that raster orientation played a major role in the impact resistance of a 3D printed structure in comparison to other process parameters. The order of influence of process parameters on the impact strength of specimens was disclosed by the mean effect plots. In terms of processing time and cost, the post-processing heat-treatment approach was found to be convenient compared to the water absorption technique.

This paper presents a new set of low-cost post-processing techniques (water-absorption and heat-treatment) for improving the impact strength of 3D printed specimens.

There is a tremendous growth of housing stock with subsequent resource consumption due to rapid urbanization. Most of the existing small-scale constructions have no planning, leading to both environmental degradation and negligible resilience to hazards. The contemporary sustainability and green building concepts are difficult to apply to small individual housing units but a collective regional assessment can be made. The regulatory bodies need to assess regions for resiliency and sustainability to prioritize fund allocation. Due to varying housing typologies and unaccounted resource consumption, reliable spatial information/data are not available to quantify risks and sustainability. The paper aims to discuss these issues.

The fuzzy logic approach has been used here to propose a regional assessment factor to give a coarse relative status of each region (and not individual houses). The criterion considered incorporates both hazard safety and environmental aspects.

A model of fuzzy technique for order preference by similarity to ideal solution based on experts’ linguistic opinions has been designed with appropriate negations for prioritizing regions.

This paper anticipates that apart from pressing the need for increasing resilience to hazards, this simplified opinion-based tool will assist the government and administrators to prioritize and strategize their funds/efforts toward achieving safety and sustainability. Depending on the evaluation and assessment, specific retrofits can be planned and executed. The assessment may be used by NGOs working in housing sector and architects and engineering professionals or academicians.

An amalgamation of Decision-Making Trial and Evaluation Laboratory (DEMATEL) and Analytical Network Process (ANP) has been performed to develop a decision-making framework for improving the overall performance of the microfinance institutions. A primary survey was conducted to collect real-time data from the heterogeneous stakeholders of microfinance institutions across India. The validation of the proposed framework is performed by comparing the results against the conventional method of Analytical Hierarchy Process (AHP).

This study identifies various dimensions and indicators for measuring the performance of Indian microfinance institutions. Additionally, the ranking and prioritisation of the performance dimensions and indicators is obtained by considering the mutual interrelation between them.

The study indicates that there exists a significant dyadic relationship between financial performance and social performance for improving the overall performance of the microfinance institutions. Governance is found to unidirectionally influence both financial and social performance. Among all the considered dimensions, financial performance of a microfinance institution is the most critical dimension for improving the overall performance. The top five performance indicators of the Indian microfinance institutions are funding source, borrowing and overhead cost, size of the firm, end-use of the money and depth of outreach.

The study was conducted in the context of Indian microfinance institutions; hence the scope of generalisation of the results is limited. This research considers both subjective and objective aspect of the performance dimensions and indicators from the perspective of multiple stakeholders (i.e. firm, society and regulator). The integrated framework is expected to aid in improving overall performance of microfinance institutions by focusing on the most critical (high prioritised) performance indicators.

An integrated DEMATEL-ANP framework is used in the domain of microfinance to assess the performance dimensions. This study is unique in terms of analysing performance of microfinance institutions from the perspective of heterogeneous stakeholders.

The purpose of this study is to identify, analyse and model the post-processing barriers of 3D-printed medical models (3DPMM) printed by fused deposition modelling to overcome these barriers for improved operational efficiency in the Indian context.

The methodology used interpretive structural modelling (ISM), cross-impact matrix multiplication applied to classification (MICMAC) analysis and decision-making trial and evaluation laboratory (DEMATEL) to understand the hierarchical and contextual relations among the barriers of the post-processing.

A total of 11 post-processing barriers were identified in this study using ISM, literature review and experts’ input. The MICMAC analysis identified support material removal, surface finishing, cleaning, inspection and issues with quality consistency as significant driving barriers for post-processing. MICMAC also identified linkage barriers as well as dependent barriers. The ISM digraph model was developed using a final reachability matrix, which would help practitioners specifically tackle post-processing barriers. Further, the DEMATEL method allows practitioners to emphasize the causal effects of post-processing barriers and guides them in overcoming these barriers.

There may have been a few post-processing barriers that were overlooked by the Indian experts, which might have been important for other country’s perspective.

The presented ISM model and DEMATEL provide directions for operation managers in planning operational strategies for overcoming post-processing issues in the medical 3D-printing industry. Also, managers may formulate operational strategies based on the driving and dependence power of post-processing barriers as well as the causal effects relationships of the barriers.

This study contributes to identifying, analyzing and modelling the post-processing barriers of 3DPMM through a combined ISM and DEMATEL methodology, which has not yet been reviewed. This study also contributes to decision makers developing suitable strategies to overcome the post-processing barriers for improved operational efficiency.

Industrial Relations and People Management.

Graduate or Postgraduate level, Executive working in manufacturing sector.

This case highlights the industrial relation issues in a public sector undertaking, a government-owned company in India. The case depicted the issues taken place in the company in the year 2015-2016. The primary data were collected by a working professional, who dealt with and was involved in the scenarios discussed in the case. Other modes such as in-depth interviews were also taken as per requirements. This case also highlights the importance of roles of unions and association in these organizations. Factors which are important to maintain industrial harmony were analyzed and their perspective with respect to production loss were addressed.

Every employee must be dealt with in a dignified manner with rationale. Hierarchy is required to be in place but doesn’t need to be authoritative. Be communicative and transparent while taking action. There should be no compromise on indiscipline at workplace and decision to be taken accordingly. Manage conflict by involving all the concerned authorities from outset. The analysis of the case shows that if the rationale was followed while managing the people it will lead to industrial harmony. Role of trade unions and association will prove beneficial as they will become a part of creating a solution in the matter of discords, ensuring growth for the company and its employees. It is important to mention here that the case was developed on the basis of the first-hand experience of the author.

Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

CSS 6: Human Resource Management.

The purpose of this paper is to identify the key elements of digitalization for lean and green operations and develop a conceptual framework for their implementation. The paper focuses on small and medium-sized enterprises (SMEs) and aims to explore the role of digitalisation in enhancing their operational efficiency and sustainability. By identifying key factors and metrics related to digitalisation, the paper seeks to provide insights for strategic management to improve lean and green practices in SMEs.

Interpretive structural modeling (ISM) and Matrix of Cross-Impact Multiplication Applied to a Classification (MICMAC) approaches were deployed to classify the major dimensions of digitalisation. These methods were used to analyse the direct and indirect relationships among the identified elements of digitalisation. A comprehensive literature review and expert consultations were conducted to identify 13 key elements relevant to lean and green operations. The experts also assisted in determining the contextual relationships between the variables for the ISM model.

The analysis classified the 13 identified elements of digitalisation into different levels according to their driving power and dependence. The results from the ISM model indicated three levels of classifications. At level-1, Internet of things (IoT) and smart sensors (IoT & SS), automation and robotics directly influence lean and green operations. At level-2, real-time monitoring and control system and at level-3 fundamental elements of digitalisation such as big data analytics, predictive maintenance, cloud computing, energy management systems (EMSs), additive manufacturing, blockchain, digital workflow automation and digital collaboration platform.

All elements are interrelated and essential for making strategic decisions. This study emphasis the significance of prioritising these attributes to attain long-term excellence through digitalisation. For the industries that seek the reward of lean and green operations for their growth, this paper has great practical utility. Identifying the key factors of digitalisation would help strategic managers in handling lean and green environment of SMEs through these aspects.

This study, based on the instrumental approach of the stakeholder theory, examines the firm performance of public and private sector firms in the mandatory corporate social responsibility (CSR) expenditure regime in India. CSR was legislated in India in the year 2014.

The study hypothesizes that firms which fulfill the mandatory CSR expenditure requirement will have a higher firm performance and uses one-way ANOVA and post-hoc test for analysis. Firm performance is examined with respect to firm value and market performance.

The instrumental approach of the stakeholder theory is not supported in the mandatory CSR expenditure regime in India. The public sector firms that comply with the mandatory CSR expenditure requirement have a lower firm performance. Further, the private sector firms that meet the mandatory CSR expenditure criterion do not have a significantly different firm performance than the private sector firms that do not fulfill this criterion.

The study indicates as to why some firms fail to meet the CSR expenditure compliance. It also gives suggestions on how regulators and government agencies can solicit the participation of the Indian firms to undertake CSR initiatives. The study further suggests how firms may reap maximum benefit from the CSR expenditure.

Since CSR expenditure has been made mandatory only in the year 2014 in India, hardly any study has examined firm performance in the mandatory CSR expenditure regime in India.