Fred L. Amorim, Armin Lohrengel, Volkmar Neubert, Camila F. Higa and Tiago Czelusniak
This work is focused on the investigation of direct production of electrical discharge machining (EDM) electrodes through the selective laser sintering (SLS) technique using a new…
Abstract
Purpose
This work is focused on the investigation of direct production of electrical discharge machining (EDM) electrodes through the selective laser sintering (SLS) technique using a new metal-matrix composite material made of molybdenum and a copper-nickel alloy (Mo-CuNi). The influence and optimization of the main SLS parameters on the densification behavior and porosity is experimentally studied. Additionally, EDM experiments are performed to evaluate the electrodes performance under different machining conditions. The paper aims to discuss these issues.
Design/methodology/approach
The new EDM electrode material used was a powder system composed of Mo and pre-alloyed CuNi. A systematic experimental methodology was designed to evaluate the effects of layer thickness, laser scan speed and hatch distance. The densification behavior, porosity and surface morphology of the samples were analyzed through microstructural and surface analysis. EDM experiments were conducted under three different regimes in order to observe the electrodes behavior and performance. The results were compared with copper powder electrodes manufactured by SLS and solid copper electrodes EDMachined under the same conditions.
Findings
The experimental results showed that the direct SLS manufacturing of composite electrodes is feasible and an adequate combination of parameters can produce parts with good quality. The laser scan speed has a great effect on the densification behavior of the samples, while the effect of hatch distance on the porosity is more visible when the overlapping degree is considered. The overlapping also had a significant effect on the surface morphology. The EDM results showed that the Mo-CuNi electrodes had superior performance to the copper powder electrodes made by SLS for all the EDM regimes applied, but inferior to those achieved with solid copper electrodes.
Originality/value
Significant results on the direct SLS manufacturing of a new material which has a great technological potential to be used as an EDM electrode material are presented. Valuable guidelines are given in regard to the SLS optimization of Mo-CuNi material and its performance as an EDM electrode. This work also provides a systematic methodology designed to be applied to the SLS process to produce EDM electrodes.
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Tiago Czelusniak and Fred Lacerda Amorim
This paper aims to provide a detailed study on influence of the laser energy density on mechanical, surface and dimensional properties of polyamide 12 (PA12) parts produced by…
Abstract
Purpose
This paper aims to provide a detailed study on influence of the laser energy density on mechanical, surface and dimensional properties of polyamide 12 (PA12) parts produced by selective laser sintering (SLS), providing the microstructural and crystallization evolution of the samples produced at different energy densities.
Design/methodology/approach
Making use of a space filling design of experiments, a wide range of laser sintering parameters is covered. Surface morphology is assessed by means of profile measurements and scanning electron microscopy (SEM) images. Mechanical testing, SEM, X-ray diffraction (XRD), differential scanning calorimeter (DSC) and infrared spectroscopy (FTIR) were used to assess the influence of energy density on structural and mechanical properties.
Findings
Results show a high dependency of the properties on the laser energy density and also a compromise existing between laser exposure parameters and desired properties of laser sintered parts. Surface roughness could be associated to overlap degree when using higher scan line spacing values and lower laser speeds improved surface roughness when high scan line spacing is used. Higher mechanical properties were found at higher energy density levels, but excessively high energy density decreased mechanical properties. A transition from brittle to ductile fracture with increasing energy density could be clearly observed by mechanical analysis and SEM. XRD and DSC measurements show a decrease on the crystal fraction with increasing energy densities, which corroborated the plastic behavior observed, and FTIR measurements revealed polymer degradation through chain scission might occur at too high energy densities.
Originality/value
Valuable guidelines are given regarding energy density optimization for SLS of PA12 considering not only quality criteria but also microstructure characteristics. Surface properties are studied based on the concept of degree of overlap between laser scanning lines. For the first time, crystallization behavior of SLS PA12 parts produced at different energy levels was studied by means of XRD measurements. Polymer degradation of SLS PA12 parts was evaluated with FTIR, which is a non-destructive and easy test to be conducted.
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Camila Fernandes Higa, Thatyanne Gradowski, Selene Elifio-Esposito, Marcelo Fernandes de Oliveira, Paulo Inforçatti, Jorge Vicente Lopes da Silva, Fred Lacerda Amorim and Michelle Sostag Meruvia
This study aims to investigate the production of scaffolds by selective laser sintering (SLS) using poly(vinyl alcohol) (PVA) polymer, for in vitro studies, a relatively new and…
Abstract
Purpose
This study aims to investigate the production of scaffolds by selective laser sintering (SLS) using poly(vinyl alcohol) (PVA) polymer, for in vitro studies, a relatively new and growing area in which scaffolds could be used in the design of three-dimensional models for in vitro disease model or tissue equivalent for safety and effectiveness tests.
Design/methodology/approach
The influence of the SLS process parameters laser power, 26 W and 32 W, and number of laser scans, 1, 2, 4 and 6, on the surface microstructure of the samples and on the degree of crystallinity and chemical stability of PVA material, was investigated using powder with particle size of 20-320 µm. Laser sintered PVA samples were subjected to cell culture tests using osteoblastic cells derived from human osteosarcoma (SaOs-2).
Findings
The laser power has no significant influence on the microstructure of the laser-sintered samples, however the number of scans has a considerable influence on the sintering degree; the SLS process causes a decrease in the degree of crystallinity and changes the chemical structure of the as-received PVA, especially when using higher laser power and more number of scans. Preliminary in vitro cell culture tests show that the laser-sintered PVA material is biocompatible with SaOs-2 cells.
Originality/value
SLS offers good potential for the fabrication of scaffolds and thus, may be applied as an alternative to conventional scaffold fabrication processes to overcome their limitations.
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Fred Lacerda Amorim, Armin Lohrengel, Guenter Schaefer and Tiago Czelusniak
This work aims to investigate the direct production of electrical discharge machining (EDM) electrodes by means of the selective laser sintering (SLS) technique using a new…
Abstract
Purpose
This work aims to investigate the direct production of electrical discharge machining (EDM) electrodes by means of the selective laser sintering (SLS) technique using a new non-conventional metal-matrix composite material (TiB2-CuNi). The influence and optimization of the main SLS parameters on the densification behavior and porosity is experimentally studied. EDM experiments are also performed to evaluate the electrodes performance.
Design/methodology/approach
The new EDM electrode material used was a powder system composed of TiB2 and CuNi. Making use of a designed systematic experimental methodology, the effects of layer thickness, laser scan speed and scan line spacing were optimized, where aspects such as densification behavior, porosity and surface morphology of the samples were analyzed through microstructural and surface analysis. EDM experiments were conducted under three different regimes in order to observe the electrodes behavior and performance. The results were compared with copper powder electrodes manufactured by SLS and EDMachined under the same conditions.
Findings
The experimental results showed that the direct SLS manufacturing of composite electrodes is feasible and promising. The laser scan speed has a high effect on the densification behavior of the samples, while the effect of scan line spacing on the porosity is more visible when the overlapping degree is considered. Surface morphology was not affected by the scan line spacing, whereas balling phenomenon was reported, regardless of the scan line spacing. The EDM results showed that the TiB2-CuNi electrodes had a much superior performance than the copper powder electrodes made by SLS, regardless of the EDM regime applied.
Research limitations/implications
Generally, the machine tool itself promotes some restrictions to the SLS process optimization. It is normally attributed to the characteristics of the laser type and the amount of energy that can be delivered to the powder bed. The present investigation could not cover all the optimization potential involved with the studied material due to limitations of the SLS machine tool used.
Originality/value
Significant results on the direct SLS manufacturing of a new non-conventional composite material, which has a great technological potential to be used as an EDM electrode material, are presented. Valuable guidelines are given in regard to the SLS optimization of TiB2-CuNi material and its performance as an EDM electrode. This work also provides a systematic methodology designed to be applied to the SLS process to produce EDM electrodes.
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The purpose of this paper is to evaluate the interrelationship between process recovery, employee recovery and customer recovery in a financial services call centre. The authors…
Abstract
Purpose
The purpose of this paper is to evaluate the interrelationship between process recovery, employee recovery and customer recovery in a financial services call centre. The authors also investigate how process recovery affects customer recovery via employees – the bridge between organisation and customers.
Design/methodology/approach
A case study–based approach is adopted in this study, and data triangulation is achieved through multiple data collection methods including semi-structured interviews, employees’ survey and company reports. Justice theory is the theoretical lens considered to understand the “service recovery (SR)” phenomenon.
Findings
This paper helps in understanding the relationship of process and employee recovery with customer recovery. Findings suggest that SR could be used for complaint management as well as in understanding and addressing the gaps in internal operations and employee skill sets. Factors such as training, operating systems, empowerment, incentives, and feedback were identified as critical in providing effective SR. Process improvement is necessary to control complaints by conducting root cause analysis and learning from failure.
Research limitations/implications
Findings are limited to a case company in financial services sector and thus limit its generalisability to other context. Questionnaire distributed to employees only included important dimensions of SR, which would be further developed in future research.
Originality/value
This paper explores the specific reverse exchange strategies, termed in this paper as SR, and analyses the different factors responsible for better performance in the exchange process. The paper highlights how the imbalance in the process and employee recovery dimensions can impact on customer recovery. Closing the customer complaint loop by using the SR perspective may help organisation to not only deal with complaints in a better way but also prevent such complaints in the future.
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Gina G. Barker, Fred Volk and Clay Peters
The purpose of this study was to examine the possibility that culture influences burnout. Characterized by emotional, cognitive and physical exhaustion, burnout stems from…
Abstract
Purpose
The purpose of this study was to examine the possibility that culture influences burnout. Characterized by emotional, cognitive and physical exhaustion, burnout stems from chronic, unresolvable stress experienced when resources to meet demands are insufficient or inaccessible. This study investigated whether people in the US experience burnout differently than people in Sweden.
Design/methodology/approach
The relationship between demands and burnout was hypothesized to be mediated by perceived stress, role conflict and role ambiguity. Country was hypothesized to moderate these relationships. Data collected through surveys from Swedish and American participants were analyzed using a process macro model.
Findings
The results showed demands as positively related to burnout. This relationship was mediated by perceived stress and the mediation was moderated by country with a stronger effect for Swedes. The relationship between demands and role conflict was significant and moderated by country; however, role conflict did not predict burnout. Role ambiguity was not a significant predictor or mediator. After accounting for covariates and predictors, demands generated unique variance in burnout and country played a moderating role in this direct relationship, which was stronger for Americans than Swedes.
Originality/value
The results suggest that culture may play a role in the burnout process. Although a global issue, between-country differences and cultural influences on burnout have received little attention, even though shared culture governs perceptions, identities, roles, norms and practices associated with known predictors of burnout. By examining burnout cross-culturally, this study adds to the limited literature on burnout processes across different professional contexts.
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Gisele Mazon, Thiago Coelho Soares, Robert Samuel Birch, Jonas Schneider and José Baltazar Salgueirinho Osório de Andrade Andrade Guerra
This study aims to discuss the influences of green innovation processes on sustainable development and proposes a research model linking green absorptive capacity, green dynamic…
Abstract
Purpose
This study aims to discuss the influences of green innovation processes on sustainable development and proposes a research model linking green absorptive capacity, green dynamic capabilities and green service innovation with the aim of clarifying how these interactions operate within universities.
Design/methodology/approach
Supported by a survey of sustainability researchers in Brazilian universities, a mediation‐moderation analysis and partial least squares structural equation modelling approach is used to examine the influence of green absorptive capacity and green dynamic capabilities on green service innovation.
Findings
This study reinforces that greening processes and products are relevant to an organization and provide information on the mechanisms for achieving greater sustainable performance.
Research limitations/implications
Considering one of the dimensions of administrative science as being university management, this study provides information on the mechanisms to achieve better sustainable development in universities.
Practical implications
This study contributes to the debate by adding the perception of university managers and provides guidance on new forms of management, which allows them to face changes while minimizing the disruption to the formation of organizational knowledge.
Social implications
Universities are becoming increasingly active in promoting societal changes toward sustainable development. It is intended that the results of this research contribute to future research and act as a reference for researchers, professionals and policymakers.
Originality/value
The concept of green absorption capacity in universities is relatively new and has not yet been investigated completely with respect to its association with university management and organizational structures.
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P.Christopher Earley and Elaine Mosakowski
To guide scholars interested in incorporating culture into research on behavior in organizations, this chapter discusses cross-level approaches to the study of culture that go…
Abstract
To guide scholars interested in incorporating culture into research on behavior in organizations, this chapter discusses cross-level approaches to the study of culture that go beyond simplistic comparative analyses. We focus on the major issues confronting a cross-cultural management researcher. We consider diverse theoretical, research design, and analytical approaches that allow the researcher to link culture to organizational behavior. A central theme in our discussion is the paramount importance of a model that specifies mechanisms that link culture to lower levels of analyses, such as organizations, teams, and individuals. Our recommendations for empirical research revolve around the informed use of cross-level theoretical models to guide research design and analytical choices. We conclude with general recommendations for future research on culture and behavior in organizations.
Using surveys of Amazon and Tmall Global users, this paper aims to empirically investigate the issue of platform technological selection. We explore the impact of switching costs…
Abstract
Purpose
Using surveys of Amazon and Tmall Global users, this paper aims to empirically investigate the issue of platform technological selection. We explore the impact of switching costs on users’ intentions to use an app-enabled cross-border e-commerce (CBEC) platform based on an extended technology acceptance model (TAM). The results suggest that the higher the switching cost of a platform is, the greater the users’ satisfaction and intention to use this platform. Therefore, for the platform, a moderate switching cost will be beneficial for retaining users.
Design/methodology/approach
Based on the TAM, this paper takes the switching costs as the starting point and focuses on exploring the relationships among switching costs, perceived usefulness, perceived ease of use, perceived reliability, satisfaction and intention to use. Online surveys of users of Amazon and Tmall Global are adopted as the main instruments of this research. We collected a total of 408 valid responses from Amazon users and 490 from Tmall Global users. For the data analysis, this study conducts frequency analysis, a test analysis of the reliability and validity of the measures, correlation analysis, and path analysis using a structural equation model.
Findings
The results show that switching costs positively affect the users’ satisfaction and intentions to use a CBEC platform through perceived usefulness, perceived ease of use and perceived reliability.
Research limitations/implications
The questionnaire respondents were predominantly Chinese due to the constraints of the survey conditions. In fact, China has a high penetration rate in CBEC, and Chinese users have rich experience using the Amazon and Tmall Global platforms.
Practical implications
The development of CBEC has ups and downs, and users frequently switch platforms. Considering how platforms can stand out from the crowd and retain users, we believe that a moderate increase in the switching cost of the platform is helpful for companies to address these problems, and the implications of the results are particularly valid for decision-makers of CBEC platforms and companies.
Social implications
Amazon and Tmall Global are the two largest CBEC platforms in the world. Using these two companies as examples for comparison can effectively identify the differences between the platforms and the conclusions are representative. We suggest that platforms can improve user satisfaction and willingness to use by establishing VIP communities, issuing coupons, providing shipping services as well as convenient after-sale complaint channels, and improving the platform’s easy-to-use interface, as ways to further enable the platform to retain more users and stand out in fierce competition.
Originality/value
This paper addresses an interesting and practical issue related to the effects of introducing switching costs in an extended TAM applied to CBEC platforms.
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Adele Berndt and Corné Meintjes
Family businesses feature prominently in economies, including the South African wine industry, using websites to convey their family identity. This research paper aims to explore…
Abstract
Purpose
Family businesses feature prominently in economies, including the South African wine industry, using websites to convey their family identity. This research paper aims to explore the family identity elements that family wineries use on their websites, their alignment and how these are communicated online.
Design/methodology/approach
Based on Gioia’s methodology, a two-pronged approach was used to analyze 113 wineries’ websites’ text using Atlas. ti from an interpretivist perspective.
Findings
South African wineries use corporate identity, corporate personality and corporate expression to illustrate their familiness on their websites. It is portrayed through their family name and heritage, supported by their direction, purpose and aspirations, which emerge from the family identity and personality. These are dynamic and expressed through verbal and visual elements. Wineries described their behaviour, relevant competencies and passion as personality traits. Sustainability was considered an integral part of their brand promise, closely related to their family identity and personality, reflecting their family-oriented philosophy. These findings highlight the integration that exists among these components.
Practical implications
Theoretically, this study proposes a family business brand identity framework emphasising the centrality of familiness to its identity, personality and expression. Using websites to illustrate this familiness is emphasised with the recommendation that family businesses leverage this unique attribute in their identity to communicate their authenticity.
Originality/value
This study contributes to understanding what family wineries communicate on their websites, specifically by examining the elements necessary to create a family business brand based on the interrelationship between family identity, personality and expression with familiness at its core, resulting in a proposed family business brand identity framework.