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This paper aims to present an investigation into the variation of scan vector hatch rotation strategies in selective laser melting (SLM), focussing on how it effects density, surface roughness, tensile strength and residual stress.

First the optimum angle of hatch vector rotation is proposed by analysing the effect of different increment angles on distribution of scan vectors. Sectioning methods are then used to determine the effect that the chosen strategies have on the density of the parts. The top surface roughness was analysed using optical metrology, and the tensile properties were determined using uni-axial tensile testing. Finally, a novel multi-support deflection geometry was used to quantify the effects of rotation angles on residual stress.

The results of this research showed that the hatch rotation angle had little effect on the density, top surface roughness and strength of the parts. The greatest residual stress deflection was measured parallel to unidirectional scan vectors. The use of hatch rotations other than alternating 90° showed little benefit in lowering the magnitude of residual stresses. However, the use of rotation angles with a good suitability measure distributes stresses in all directions more evenly for certain part geometries.

All samples produced in this work were made from commercially pure titanium, therefore care must be taken when applying these results to other materials.

This paper serves to increase the understanding of SLM scanning strategies and their effect on the properties of the material.

The purpose of this paper is to investigate the forces driving organizational innovation, particularly CEO transformational leadership as it affects external and internal social capital in top management teams.

Survey questionnaires were administered to 90 Chinese top management teams. Structural equation modeling was used to test the hypothesized relationships.

Both internal and external social capital mediated the relationship between transformational leadership and organizational innovation.

Organizations should strengthen internal and external capital of top management teams to reap maximal innovation outcomes from transformational leadership.

The findings contribute to the transformational leadership, social capital, and innovation literature first by showing how leadership influences innovation through largely neglected mechanisms – internal and external social capital. Second, a social capital focus challenges the tacit assumption that transformational leadership has only internal influences by showing that it potentially spills over to the external domain.

The purpose of this paper is to report on research into the impact of two sequential dimensions of strategic purchasing – purchasing recognition and purchasing involvement – on the development and deployment of dynamic capabilities. The authors also examine how such dynamic capabilities impact on both cost and innovation performance, and how their effects differ for service as opposed to manufacturing firms.

The authors test hypotheses using structural equation modeling of survey data from 309 manufacturing and service firms.

From a dynamic capability perspective, the analysis supports the positive relationships between purchasing recognition, purchasing involvement, and dynamic capability in the form of knowledge scanning. The authors also find support for the positive impact of knowledge scanning on both cost and innovation performance. From a contingency perspective, data supports hypothesized differences caused by industry, whereby service-based firms experience stronger positive linkages in our model than manufacturing-based firms. Finally, emerging from the data, the authors explore a re-enforcing effect from cost performance to purchasing involvement, something that is in line with the dynamic capabilities perspective but not typically addressed in operations management (OM) research.

The research offers a number of theoretical and managerial contributions, including being one of a relative few examples of empirical assessment of dynamic capability development and deployment; examining the enablers of dynamic capability in addition to the more commonly addressed performance effect; assessing the contingency effect of firm type for dynamic capabilities; and uncovering a return (re-enforcing) effect between performance and enablers of dynamic capabilities.