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Purpose This paper aims to examine the relationship between supply integration and firm performance by first, investigating the mediating effects of manufacturing flexibility and mass customization; and second, exploring the moderating role of innovation orientation on the link between internal capabilities and performance. Design/methodology/approach Resource orchestration and contingency theories are used to address the mediating and moderating effects. A cross-sectional data set on 242 Swedish manufacturers is used to test for the hypotheses using structural equation modeling. Findings The findings provide support for the mediating roles of manufacturing flexibility and mass customization in the relationship between supply integration and firm performance. However, the results point to contrasting contingent effects of innovation orientation. While innovation orientation positively moderates the association between mass customization and firm performance, it shows a negative impact on the link between flexibility and performance. Research limitations/implications The study contributes to the literature on the integrative activities with upstream supply chain actors. Specifically, the authors highlight how specific capability configurations comprising of supply integration, manufacturing flexibility and mass customization lead to firm performance. Moreover, the authors provide insights on the contingency role of innovation, especially if firms consider flexibility or customization capabilities. Originality/value While the individual impacts of flexibility and customization on performance have been addressed previously, there is a paucity of research on how these two capabilities are integrated with supply integration. Moreover, there is little known regarding the role of innovation orientation on these integrated relationships.

Non-fungible tokens (NFTs) are a highly nascent and emerging phenomenon revolutionizing how digital assets are traded. NFTs embody immutable rights to unique digital assets such as digital art and collectibles, and are represented as digital tokens that can be traded across marketplaces utilizing blockchain technologies. NFTs engender new ways to organize, consume, move, program, and store digital information, and have experienced a rapid rise in various adaptations across art, sport, broadcasting, content creation, and tech-crypto business. This paper explains what NFTs are, how they fit with blockchain and cryptocurrencies, how they are used by various industries, and what opportunities and risks they present. Our key contribution is to conceptually map an initial NFT ecosystem. In doing so, we provide relational mapping between and among key stakeholders including content creators, core and related technical and business intermediaries, consumers, investors and speculators. Further, the paper highlights implications for managers and ties them to conceptual exploration and exploitation frameworks. We also provide limitations and prescient understanding about the likely trajectories for NFTs.

PurposeTo examine the interplay between sustainable supply chain management (SSCM) and circular economy, this research conceptualises and empirically tests an integrative framework of environmental information exchange with suppliers (ES), environmental product design (EPD) and cost performance (CP) with the contingency effect of digital orientation (DO). The associations proposed in the integrative framework provide a configuration of SSCM practices that support circular economy's restorative processes in the digital age.Design/methodology/approachThe resource orchestration theory and contingency theory are used to investigate the mediation and moderating effects, which were tested by a moderated mediation analysis of survey data of 100 firms in Australia.FindingsThe results show that EPD fully mediates the relationship between ES and CP. Further, DO was found to moderate the relationship between EPD and CP, but not the relationship between ES and EPD.Practical implicationsThe empirical findings of this study offer an effective SSCM practice configuration for firms seeking to target advanced circular business models and economic benefits. Managers should be aware that ES may not be enough to improve CP; EPD is a required mechanism to translate the ES benefits into cost superiority. Managers should also stimulate a DO culture to develop effective EPD capabilities, which leads to improved CP and a foundation for companies seeking to target circularity.Originality/valueThis study advances prior theoretical and practical knowledge. The authors propose and empirically test an integrated SSCM and circular economy model that incorporates mediation and moderation effects to clarify inconsistent findings in prior work, which provides a more holistic and practical understanding of SSCM practices in the digital context. Furthermore, the SSCM literature recommends the adoption of circular economy principles. The integrated model in this study provides a bridge between SSCM and circular economy.

PurposeOur study advances theory in supply chain resilience (SCRes) by identifying and describing the mechanisms through which interorganizational relationships (IORs) contribute to SCRes.Design/methodology/approachWe employ a multi-method conceptual development design combining structured and narrative review of the literature, supported by illustrative case studies. A four-stage refinement process was used for data reduction, and analysis was informed by complex adaptive systems (CAS) theory.FindingsOur findings identify connectivity, collectivity and scalability as key mechanisms through which relationships between organizations contribute to SCRes. These mechanisms draw on IOR elements of information sharing, decision synchronization and incentive alignment to augment self-organization and emergence, and adaptation and coevolution via modifying/advancing resilience strategies and practices.Originality/valueOur study advances theory and practice of SCRes by expounding on how connectivity, collectivity and scalability act as mechanisms that drive and diffuse the contribution of resilient strategies/practices to resilience capability. This is significant for strategic alignment between IORs and SCRes.

The growing number of studies on road network pricing requires adoption of systematic methodologies to assess research outcomes and provide an unbiased summary of research findings and lessons learned. This paper aims to identify and analyse primary studies related to a set of research questions on road network pricing that primarily address the effectiveness of road network pricing as a travel demand management strategy. The paper achieves this by consolidating the fragmented evidence on the topic and identifying the role of transport pricing in steering our post-pandemic cities on a path of sustainable urban mobility. The paper uses a reliable and auditable systematic approach to examine past and current research trends, resulting in a rational assessment of the role and impacts of road network pricing as a travel demand management strategy. The paper achieves this by performing a bibliometric citation analysis that identifies 105 articles of valuable research contributions that represent fundamental knowledge in the development of research covering the period between 2007 and 2020. Importantly, the review identifies four main research themes in the literature, namely implementation impacts, innovations in technology, acceptability, and modelling methodologies for determining impacts, that are core elements of the research effort on the travel demand management and sustainability aspects of road pricing. Inductive reasoning is then used to address emerging issues, applications, and the effects of road network pricing in reducing congestion and enhancing urban centre environmental quality. The paper concludes with a discussion of policy directions for overcoming barriers to the implementation of road network pricing as an effective strategy for addressing modern-day urban mobility challenges such as rising urban populations, emissions, and pollution particularly amid and post COVID-19. Finally, the paper provides a roadmap of future research opportunities that can heighten the role of road network pricing in shaping the directions of sustainable urban transport policies and strategies.

Accurate counting and measurement of logs (known as log scaling) stacked in piles, is an integral part of the wood log supply chain. Currently, these tasks are manual, and hence labour intensive and prone to human errors. In this paper, we present LogLiDAR an IoT sensing-based solution for counting and scaling logs using LiDAR (Light Detection and Ranging) images. LogLiDAR incorporates an interactive user interface to explore log counting and scaling. The underlying system for processing LiDAR images is developed using a pipeline of point cloud library (PCL) algorithms. This work is the first attempt to develop an IoT-based (LiDAR) solution for counting and scaling logs for the log industry.

As increasing transportation costs mounts pressure on the businesses, there has been an increasing interest on vehicle routing problem (VRP) as a viable and effective solution. Both industry and academia are continuously looking for new approaches to save transport cost and time while increasing profit margins. This endeavor will eventually reduce costs of delivering goods and services for customers, and therefore enhancing the competitiveness of firms involved. Particularly, transportation cost savings could have potential impacts on marketing activities of remanufactured and recycled products in reverse logistics chains. Therefore, developing practical solutions for VRP of original and remanufactured products is one the emerging topics in the current transportation research. In this article, we propose a multi-objective non-linear programming model for the green vehicle routing problem (GVRP), including original and remanufactured products distribution (both delivery and pickup) of end of life (EOL) products. Through the appropriate fuzzy approach the model is linearized, validated, and solved. The results show considerable level of improved performance under the model configurations and proposed solution approach. The obtained results clearly indicate that the proposed mathematical model is capable of reducing the fuel cost, distribution center set-up cost and supplying vehicles, as well as minimizing air pollution. Finally, using a real case study the reliability and viability of the proposed model is verified.

This paper presents a systematic review of studies related to artificial intelligence (AI) applications in supply chain management (SCM). Our systematic search of the related literature identifies 150 journal articles published between 1998 and 2020. A thorough bibliometric analysis is completed to develop the past and present state of this literature. A co-citation analysis on this pool of articles provides an understanding of the clusters of knowledge that constitute this research area. To further direct our discussions, we develop and validate an AI taxonomy which we use as a scale to conduct our bibliometric and co-citation analyses. The proposed taxonomy consists of three research categories of (a) sensing and interacting, (b) learning, and (c) decision making. These categories collectively establish the basis for present and future research on the application of AI methods in SCM literature and practice. Our analysis of the primary research clusters finds that learning methods are slowly getting momentum and sensing and interacting methods offer an emerging area of research. Finally, we provide a roadmap into future studies on AI applications in SCM. Our analysis underpins the importance of behavioral considerations in future studies.

Previous research presents mixed findings about the impact of environmental orientation (EO) on environmental performance (EP). Using the theoretical lens of resource orchestration theory (ROT) and contingency theory (CT), this study explores the relationships between EO, external environmental information exchange (EEIE) (with suppliers and customers), and EP. In particular, this study investigates the mediating role of EEIE between EO and EP, and the moderating effect of EO on the relationship between EEIE and EP. The proposed relationships were analysed through structural equation modelling and hierarchical linear regression analysis using survey data collected in Australia. The results reveal the partial mediating effect of EEIE on the EO-EP link, and the contingency effect of EO on the relationship between EEIE (with customers) and EP. Our study extends the boundaries of the current understanding by empirically testing both mediation and moderation within the same study, thereby presenting insights into how EO can positively influence EP, and under what circumstances. These findings provide managers with useful guidance on how EO can be complemented by external information sharing for environmental solutions.

PurposeThe purpose of this paper is twofold: first, to empirically evaluate the key impediments to the competitiveness of the rail sector in Australia; and second, to provide relevant transport management and policy recommendations for enhanced competitiveness.Design/methodology/approachThis paper has adopted an empirical approach. A survey was developed and distributed among rail stakeholders in Australia. Accordingly, exploratory factor analysis and confirmatory factor analysis were conducted to evaluate the key impeding areas.FindingsThis paper found four areas that are impeding rail development, these being infrastructure management, shortage of freight data and poor information sharing, service delivery and organisational and commercial interactions.Research limitations/implicationsThe theoretical approach of this thesis can be applied to any freight market where competition exists between different transport modes. However, the specific strategies provided in this research in terms of transportation management, infrastructure planning and policy were made according to the specific market condition, infrastructure quality and regulation that exist in Australia.Practical implicationsThe findings provide important implications for both industry and government in terms of making transport planning and policy decisions, but also useful insights by identifying the weak parts of the rail sector and directions to target them.Originality/valueThe notion of the rail stakeholder does not appear to have been previously defined in the literature. Therefore, this research takes a broader view of rail stakeholders to include various interest groups within the rail sector and its operational environment.

This paper proposes a hardware in the loop simulation testbed by using airborne seekers (an onboard visual tracking system) as a relative measurement sensor in the leader-follower formation flight. To the best of the authors’ knowledge, this is the first study on experimental applications of airborne seekers in unmanned aircraft formation flight. The proposed structure gives an effective method to study the effects of uncertainties such as the camera process delay and the seeker measurement noises on formation keeping. Compensation of errors in visual measurements is considered as well.

With the advent of computers, sensor technologies and advanced data analytics, unmanned shipping is not just a concept for maritime researchers, but it has become a serious debate for the international maritime community. Early studies have revealed promising economic and environmental benefits for the users of autonomous vessels which potentially results in lower operational costs and higher safety levels. Furthermore, many researchers believe that with the current technology, it is achievable to develop and run unmanned ships capable of meeting safety and operational standards. However, future implications of unmanned vessels for the maritime industry are diverse, difficult to measure and unknown to some extent. The maritime industry is a complex industrial sector encompassing various players involved in transport, logistics, regulatory, engineering, finance and insurance activities which are vertically and horizontally intertwined. Therefore, introducing autonomous vessels will not only transform the way vessels are operated across international waters, but also comes with major ramifications for all players involved in providing an end-to-end freight transport solutions. Given this gap, this chapter's objective is to explore the policy implications of autonomous ships for the maritime industry. Our exploration identifies new cost implications and asset management challenges, examines the likely impacts of embracing autonomous ships on port and shipbuilding sectors, and also, provides an industry maturity framework and debates the potential impacts of unmanned vessels on different shipping markets.

Blockchain is an emerging technology expected to unleash disruptive and transformational forces in many fields. As a decentralized distributed digital ledger, Blockchain technology has the potential to become an underlying operating system that governs the way our cities function in the future. This paper explores the potential of Blockchain as a technology for enabling sustainable future cities and empowering citizen co-creation and participation, promoting civic engagement and achieving Smart Cities' efficiency and transparency objectives. The article first provides background to the Blockchain concept, current and emerging trends in its development, followed by a survey of potential urban applications with particular attention to the domains of governance, transport, supply chain and logistics. Next, the paper presents the challenges that must be overcome to enable widespread adoption and deployment of the technology. The paper is intended for urban researchers and practitioners alike and will be a contribution that can be used by a broad range of stakeholders who wish to understand the disruptive forces of Blockchain, opportunities and potential applications, as well as challenges in the context of Smart Cities.

The Australian domestic freight activity has doubled in size over the past 20 years, averaging growth of 3.5% per annum with the intermodal sector measuring the fastest growth rate. Thus, as the movement of freight by a variety of modes becomes a dominant model and pressure mounts to ensure that the integration of these modes is efficient and effective the role of intermodal terminals in sustaining the distribution systems becomes more prominent. Using both primary and secondary data, this paper provides an analysis of the trends in the Australian rail freight task and evaluates the current infrastructure in terms of capacity and efficiency to accommodate this trend, particularly in different sub-markets. This detailed understanding is a key facilitator for policy makers and freight operators to better utilise the available resources, as well as informed planning decisions for sustainable infrastructure developments.

Formation of wavy boundaries at the open end of a drawn cup is referred to as earing. Plastic anisotropy is the main parameter contributing to formation of ears. Therefore, in order to eliminate the undesirable ears in sheet metal parts, it is essential to predict the deformation behavior of sheet metals using advanced anisotropic yield criteria. Accordingly, the objective of this article is that to use BBC2003 yield criterion, to predict earing in deep drawing of cylindrical cups from AA3105 aluminum alloy. First, a new and simple approach is introduced to calculate the eight constants of this yield function. In this approach, only the uniaxial and plane strain tension tests results, were used. Nonlinear governing equations of these constants were derived and solved by means of well-known steepest descend method. In order to investigate performance and accuracy of this method, the calculated constants were utilized to predict normalized uniaxial yield stress, anisotropy parameters and plane stress yield surface. Then, based on this yield criterion and the associated flow rule, a VUMAT subroutine was developed and employed in the commercial finite element software ABAQUS/Explicit dynamics. The simulation of drawing process was conducted for anisotropic AA3105 aluminum alloy sheet. Cup height (earing profile) and thickness distribution were obtained from experiments and corresponding numerical simulations. Comparison of these results demonstrates great potential of BBC2003 yield criterion in accurate prediction of earing.

There has been a mounting interest in the use of image-based concrete finite element models to estimate their mechanical properties. The aim of this study is to present a new approach for determining the compressive strength of real concrete based on numerical analysis. In this study, the three-dimensional mesoscale finite element (FE) models of concrete specimens were generated based on the computed tomography (CT) images. Most models consider the concrete as a homogeneous material, whereas it is a heterogeneous composite consisting of aggregates, cement paste, and air voids. In addition, the existing heterogeneous models are limited to just one type of aggregate. In this study, two different types of aggregates were selected for concrete mix design and accordingly defined as separate phases in FE models. Two groups of concrete specimens with different water-to-cement ratios were cast. The images were taken using a medical CT scan device and converted to the manageable mesoscale hexahedron elements through the image processing accompanied with meshing technique. FE models were then built considering the mechanical properties of the individual components of concrete determined in the laboratory. Using the explicit dynamics solver of Abaqus software, compressive strength of the specimens was obtained. The compressive strengths of the three specimens with different shapes selected from the two groups of concrete (cubic group I, cubic group II, and cylindrical group II) were estimated with 8.8%, 9.7% and 8% deviations from the experimental curves. The accuracy and performance of this method makes it a potential candidate as a quality control tool for concrete structures. The findings revealed that X-ray CT (XCT) images can be utilized as a suitable method to estimate the ultimate strength of concrete based on early-aged specimens. This can greatly be of advantage to the supervisory administration.

Biomass electricity supply chains are prone to a range of uncertainties that emanate internally or externally. Therefore, design of robust supply chains that remain resilient in the face of disruptions becomes of important interest. This study presents a two-stage stochastic mixed integer non-linear programming (MINLP) model combined with chance constraint to minimize the total cost of producing electricity from woody biomass in a four-level integrated bioenergy supply chain. The strategic decisions such as location and capacity of infrastructure are incorporated into the first stage, and decisions for sourcing the materials, inventory policy and are included in the second-stage. The proposed model considers detailed climate factors such as temperature and dew point, which are highly influential on moisture content, higher heating value, energy values, and ultimately, the performance of bioenergy supply chain. Given the NP-hard nature of the problem, hybrid metaheuristic approach is proposed that benefits from genetic algorithm (GA) operators and chaos theory in the structure of an improved cross entropy (CE) algorithm. Compared to the results of exact solution, the proposed ICE performs better compared to conventional CE by 5.6%.

This research presents an optimization problem associated with scheduling of unrelated parallel machines considering the simultaneous effects of start-time-related deterioration, position-related learning and sequence-related setup times, with the aim to achieve an optimized value for the mean weighted tardiness and power consumption minimization. A workaround is proposed and served as the converter for solving the Mixed Integer Programming (MIP) problem by the continuous-based metaheuristic algorithms. Knowing the NP-hard nature of the problem, three metaheuristic algorithms, namely, Genetic Algorithm (GA), Cat Swarm Optimization (CSO) and Interactive Artificial Bee Colony (IABC), are employed to obtain quality solutions within acceptable computation time. A unique elitism strategy is introduced in the conventional CSO to reduce the computational time of its seeking mode and to provide improved solution, with the new algorithm form called CSO-Elit. Furthermore, a compact solution expression form is proposed for the use of GA, CSO-Elit and IABC to reduce the number of constraints. With the newly proposed model, many essential constraints are automatically built into the solution representation. Accordingly, the efficiency of algorithms is compared with LINGO regarding the quality of solutions, computational time, and overall power consumption using two sets of problems in small and large scales. In solving the small-scale cases, no statistically meaningful difference was observed between LINGO, GA and CSO-Elit, while in large-scale instances CSO-Elit demonstrated higher performance. The contributions of this paper lie in modeling a complex parallel machines problem considering power consumption minimization and proposing a new form of CSO algorithm with elitism strategy to reduce the computational time.

The number of containers handled by Australian seaports has quadrupled over the past two decades. This has posed major difficulties for community and businesses. Knowing the projected demand, the need for disruption-free and reliable land corridors is of emerging importance. This paper first aims to establish a transparent image of the role of rail in the Australian port-based container flows and, second, to empirically identify the key impediments to the competitiveness of rail in this market. To achieve the second objective, a survey was distributed among Australian ports and key container stevedores. This paper identifies that despite the significant growth in the container volumes, rail’s share in the land-based movement of this traffic was small, principally due to lower service levels. The analysis indicated that inadequacy of intermodal infrastructure is a key impediment for the use of rail, followed by poor interoperability and shortage of below-rail infrastructure. This paper concludes wi...

Malaysia, situated between East and West, is an interface in world maritime trade, playing a crucial role in the business of moving container boxes in South-eastern parts of Asia. The prominent container terminals in Malaysia such as Port Klang and Port of Tanjung Pelepas are positioned among the top twenty ports in terms of volume handled. The annual average growth of throughputs in Malaysian container ports increased more than three-fold from the year 2000 to 2010. Within this context, the development of Malaysian seaports has been significantly influenced by three forces: increased use of containerisation, significant growth in domestic economic activities and ever-changing patterns in both supply and demand chains, all of which have led to increased transshipment activities and altered shipping routes. This phenomenon has brought dynamic change to Malaysian container ports, resulting in the establishment of new terminals and adapting emerging technology to enhance the ports' ability to accommodate larger vessels and an increased number of containers. This paper aims to present the development of Malaysian container seaports by addressing changes to acreage size and handling volumes during the last three decades. The results of the analysis suggest that major Malaysian ports are experiencing an exponential growth in container trade with the expansion of port capacity following trade growth and need effective strategies to reduce the operational pressures of Malaysian seaports. The results of this research offer directions for development strategies of seaports by utilising the existing inland freight facilities as an effective strategy for capacity enhancement and develop efficient distribution network to meet future demands.

Purpose – The purpose of this paper is to identify current impediments to the competitiveness of the rail industry in the Australian non-bulk freight market. Design/methodology/approach – A systematic literature review was adapted to identify the impediments and challenge themes from 1,081 studies available on the Australian rail industry. To select the studies relevant to the research question, a tollgate criterion was then deployed. Impediments were identified by a structured data synthesis process and a heuristic algorithm was developed to explore the possible relationships between the impediments and challenges. Findings – Four major themes are apparent, each of which presents the rail industry with challenges in the non-bulk freight market. “Infrastructural inefficiencies and the need for further integration” was ranked as the main rail industry challenge, while “environmental concerns and the associated costs of externalities” was the least. In addition, across the four themes data synthesis identified 43 impediments from purely policy related to technical and operational aspects. Research limitations/implications – The major implication of this review is the identification of impediments that have no linkage to the four industry challenges as revealed by stakeholders in the literature. That means that the rail industry has been dealing with a number of issues that have not been explored and studied in depth either by practitioners or academics. The underlying elements of impediments in this group are perceived as managerial, organisational and leadership factors. The rail industry has failed to manage its organisational ties across the system, both horizontally and vertically. This issue has been intensified as the result of complex interactions between different transport modes and operators associated with the non-bulk freight sector. Originality/value – For the first time in the Australian context, this study provides an en masse and summarised picture of impediments to the competitiveness of the rail industry in the non-bulk freight market by systematically reviewing the reports generated by different stakeholders in the last ten years. The outcomes will assist the rail industry and government to understand impediments impacting on the quality of rail freight services that may lead to collaboration on decision-making and investment strategies.

The mechanical response of single-walled helically coiled carbon nanotubes (CCNTs) under large axial deformations is examined using a molecular dynamics finite element method. The 3D reference configuration of CCNTs is determined based on a 2D graphene layer using conformal mapping. Three sets of analyses are performed to fully describe the mechanical response of ( n , n ) CCNTs under elongation up to the bond breaking point and compression down to the solid length or the onset of buckling instability. First, the strain dependency of the mechanical properties of individual CCNTs during deformation is investigated by calculating the stress-strain curve and the spring constant of the CCNTs for the entire load range. Significant responses including brittle fracture under tension and buckling instability under compression are observed. Second, to examine the size dependence of the mechanical properties, several CCNTs with different geometric parameters are constructed, and their spring constant, fracture strain, fracture load, and energy storage density are determined. All CCNTs exhibit a superelasticity of 50–66%. A comparison between the mechanical properties of CCNTs and those of carbon nanotubes (CNTs) reveals that the fracture load and energy storage per atom of CCNTs is lower than that of the corresponding armchair CNTs.

In this paper, mechanical properties of single-walled helically coiled carbon nanotubes are investigated by means of molecular structural mechanics method in ANSYS finite element code. To specify the geometry of coiled carbon nanotubes, a construction procedure is proposed which offers a full control over the morphology of the coiled nanotubes. In this construction approach, first a development map is drawn on a graphene sheet and then this graphene sheet is rolled to form a defected straight carbon nanotube; then, the sides of these defects are stuck together through a nonlinear analysis and finally, the straight carbon nanotube forms into coiled carbon nanotube. Using this construction procedure, several coiled nanotubes are built and their spring constants are calculated. It is shown that the spring constants found are in good agreement with those obtained from density function theory and tight-binding calculations reported in the literature. Moreover, in order to facilitate the simulation of those macroscopic systems which contain coiled carbon nanotubes, an equivalent continuum model is proposed and its mechanical properties are investigated. It is found that, as the tube diameter increases, both spring constant and shear modulus of the coiled carbon nanotube increase.

In this study, aluminum alloy A5052 and magnesium alloy AZ31 were joined by conventional parallel setup of explosive welding and underwater explosive welding. Microstructural characterization of conventional welded joints revealed a characteristic wave formation with vortices and contact surface melting layer containing intermetallics. In order to reduce the vortices and melting layer, underwater explosive welding was used. The welding parameters are regulated to reduce the kinetic energy loss during collision. The low kinetic energy loss in underwater explosive welding resulted in the formation of small waves with less vortices and no melting layer.

This paper aims to empirically examine the impact of horizontal cooperation in purchasing on the lead times of the orders from suppliers. Two groups of SMEs participating in purchasing groups were investigated for a ninemonth period of data collection. However, for one of the groups involved in cooperative transportation of the purchased goods, total lead-time was measured, and further analysis was conducted. The outcomes of this study show that firms involved in purchasing consortia face significant shorter lead times up to 45%. Meanwhile, the lead times for the firms cooperating in both purchasing and transportation tasks were shorter than for the other group. Additional managerial conclusions and unique contributions are drawn. Copyright © 2012 Inderscience Enterprises Ltd.

The problem of projection of a flyer plate with a traveling distributed load and subsequent collision of it to a base plate, as applied to explosive welding, is addressed in this paper. A semi-infinite solid-perfectly plastic beam is employed to model the flyer plate subject to two transverse pressure profiles, traveling at constant speed on its top and bottom surfaces, which represent the explosion and collision loads, respectively. A steady state deformation process is considered and the analysis is developed for the pure bending and combined shear and bending deformation conditions. It follows from analysis that two plastic bending hinges form ahead and at the rear end of each pressure profile and travel at constant velocity. Furthermore, when the width of the pressure is small, the shearing deformation region is generated within the loaded area. The state of the deformation in the collision stage in contrast to the propulsion stage is discussed.

The joining of wrought magnesium alloy AZ31 and commercially pure aluminum A 1100 plates was performed using explosive welding technique. Several welds were made by changing the experimental parameters. Optical microscopy and scanning electron microscopy were employed to observe the morphological and microstructural variations at the interface boundary. The geometry of the interfacial profile varied from smooth to rippled form with increase in the level of kinetic energy delivered to the bonding zone. The microstructure at the boundary was free of porosity and showed unique diffusionless dissimilar bonding. Localized zones of solidified melt in some cases were observed in the vicinity of the bonding line of the wavy-interfaced welds. Elemental analysis revealed the complex intermixed microstructure of these regions, accompanying with compositional variation due to formation of the metastable intermetallic phase Al2Mg. The bonding strength of the welds, evaluated through shear tests, confirmed the high quality of the joints produced. Based on the experimental results the lower limit of the welding parameters which ensure achieving a satisfactory joint is proposed.