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The basic thesis espoused in this chapter is that a discourse analytic approach, that explores managers’ stories, is equally valid as a more typical case study approach that seeks confirmatory data. Depth interviews with industrial network participants are conducted and described; interviews where managers are encouraged to talk of their lived experiences, beliefs, attitudes, and intentions. Specifically, this case study presents a qualitative exploration of identity processes in industrial networks, in particular social constructions of Indian modernity. The analysis suggests what these constructions mean for the management of buyer–seller relationships (cf. Bagozzi, 1995). The study also reflects calls for more empirical research to be undertaken to improve understanding of contemporary marketing practices, especially in large emerging market economies such as India and Brazil (Dadzie, Johnston, & Pels, 2008). Discursive data were collected in the form of transcripts from semi-structured interviews with a variety of managerial participants involved in trade between New Zealand (NZ) and India. All the participants are Indian, with interviews taking place in 2006 in Delhi, Mumbai, Bangalore, and Chennai. Interviews were conducted in English; with 23 individuals representing organizations operating in the lumber, wool, horticulture, dairy, engineering, IT, tourism, and education industries, they lasted between 45 and 90 minutes, and were recorded on audio and video media. The study goes some way toward addressing the dominant Western perspective prevalent in most studies of business relationships, and shows how discourse analysis can provide a rich analytical perspective on business-to-business relationships.

The purpose of this study was to assess the suitability of micro-computed tomography as a non-destructive method to investigate the morphology of nylon 12 parts produced by high-speed sintering (HSS). The investigation of the effect of changes in the lamp power on the properties of the fabricated parts was another purpose of this study.

Nylon 12 parts were manufactured using HSS with various lamp powers. Morphological properties of the parts were measured using micro-computed tomography. Ultimate tensile strength, elongation at break and Young’s modulus of the prepared parts were determined and compared. The effect of lamp power on the properties of the parts was then studied.

This paper proposes micro-computed tomography as a suitable technique to study the 3D structure of the parts produced by HSS. The effects of lamp power on the properties of the produced parts were also discussed.

The findings could result in an improvement in customisation of the parts for various applications through varying the lamp power. The level of lamp power could be tailored to obtain suitable part properties for a target application.

This study strengthens the fact that HSS is a promising additive manufacturing technique to produce nylon 12 parts, and the properties of the parts could be maximised using a suitable level of lamp power. The results showed that micro-computed tomography could be used as an efficient technique to investigate the morphology of the sintered parts.

To investigate the effects of the infra‐red power level on sintering behaviour in the high speed sintering (HSS) process.

Single‐layer parts were produced using the HSS process, in order to determine the effect of the infra‐red power level on the maximum achievable layer thickness, and the degree of sintering. The parts were examined using both optical microscopy and contact methods.

It was initially expected that an increase in the infra‐red lamp powder might allow an increase in the depth of sintering that could be achieved, as a result of increased thermal transfer through the powder. However, results in fact indicated that there is a maximum layer thickness that can be achieved, as a result of part shrinkage in the z direction. Optical microscopy images have shown that a greater degree of sintering occurs at higher power levels, which would be expected to correspond to an improvement in the mechanical properties of the parts produced. These images also indicate that the radiation absorbing material forms in small “islands” on the powder bed surface. As sintering progresses, these islands begin to merge; this occurs to a greater extent at higher infra‐red lamp powers.

These results are based only on single layer parts. Further work will examine the sintering characteristics of multiple layer parts.

Results have shown that, whilst it is not possible to increase the achievable layer thickness of the parts produced by modifying the infra‐red lamp power, the degree of sintering can be improved greatly by increasing the power.

HSS is an entirely new process which is currently still under development; the results presented here will directly impact the direction of further development and research into this process.

The amount of radiated energy is known to be a crucial parameter in powder-bed additive manufacturing (AM) processes. The role of irradiance in the multijet fusion (MJF) process has not been addressed by any previous research, despite the key role of this process in the AM industry. The aim of this paper is to explore the relationship between irradiance and dimensional accuracy in MJF.

An experimental activity was carried out to map the relationship between irradiance and dimensional accuracy in the MJF transformation of polyamide 12. Two specimens were used to measure the dimensional accuracy on medium and small sizes. The experiment was run using six different levels of irradiance. For each, the crystallinity degree and part density were measured.

Irradiance was found to be directly proportional to part density and inversely proportional to crystallinity degree. Higher irradiance leads to an increase in the measured dimensions of parts. This highlights a predominant role of the crystallisation degree and uncontrolled peripherical sintering, in line with the previous literature on other powder-bed AM processes. The results demonstrate that different trends can be observed according to the range of sizes.

The purpose of this paper is to investigate the adoption of rapid prototyping (RP) technology using three dimensional (3D) printer for infusing agility in traditional manufacturing environment.

The computer aided design (CAD) model of a knob of an electronics switch is developed using Pro/E software. Keeping this model as a reference, CAD models of new six knobs are developed. A 3D printer is used to build the prototypes of five of those CAD models. The receptivity of the practitioners over adopting CAD models and 3D printer for achieving agility is investigated.

The sensitisation of the industry captains and employees of traditional manufacturing sector is the imperative for exploiting the power of 3D printer and achieving mass customisation.

The paper reports an original research in which the practicality of using 3D printer is investigated with the objective of enabling the traditional manufacturing companies to imbibe agile characteristics.

Additive manufacturing (AM) of thermoplastic polymers for powder bed fusion processes typically requires each layer to be fused before the next can be deposited. The purpose of this paper is to present a volumetric AM method in the form of deeply penetrating radio frequency (RF) radiation to improve the speed of the process and the mechanical properties of the polymer parts.

The focus of this study was to demonstrate the volumetric fusion of composite mixtures containing polyamide (nylon) 12 and graphite powders using RF radiation as the sole energy source to establish the feasibility of a volumetric AM process for thermoplastic polymers. Impedance spectroscopy was used to measure the dielectric properties of the mixtures as a function of increasing graphite content and identify the percolation limit. The mixtures were then tested in a parallel plate electrode chamber connected to an RF generator to measure the heating effectiveness of different graphite concentrations. During the experiments, the surface temperature of the doped mixtures was monitored.

Nylon 12 mixtures containing between 10% and 60% graphite by weight were created, and the loss tangent reached a maximum of 35%. Selective RF heating was shown through the formation of fused composite parts within the powder beds.

The feasibility of a novel volumetric AM process for thermoplastic polymers was demonstrated in this study, in which RF radiation was used to achieve fusion in graphite-doped nylon powders.

The purpose of this paper is to investigate the accuracy and repeatability of the indirect selective laser sintering of aluminium process.

This work characterised the shrinkage of indirect SLS aluminium parts during the various stages of production. Standard scale parts were measured using a Giddings and Lewis co‐ordinate measuring machine in both the green and infiltrated condition.

The experiments conducted show that most accuracy is lost during the furnace cycle and that the greatest loss of accuracy occurred in the Z dimension. Additionally the position of parts within the part bed in both X, Y and Z is shown to influence accuracy, with smaller parts being built closer to the edge of the bed later in the build. These results have been interpreted as being a result of the phenomenon of “Z‐growth”. Finally, the research shows that the overall accuracy of the indirect selective laser sintering of aluminium process is comparable with many existing processes such as investment casting.

Before any new material can be accepted, there is a need to not only fully characterise the dimensional accuracy attainable, but also to gain a thorough understanding of the processes that contribute to the inaccuracies. This paper addresses this need.

The purpose of this paper is to measure the effect of process conditions on mechanical properties of laser‐sintered nylon 12 (Duraform^®) and to determine the range of conditions that provide consistent mechanical performance for additive manufacturing.

Tensile test specimens were fabricated over a range of well‐characterized process conditions including laser power, laser speed, scan spacing, layer thickness, build orientation, and build position. Tensile modulus, yield strength, ultimate tensile strength and elongation‐at‐fracture were measured and related to process parameters.

Tensile properties are strongly related to the amount of energy deposited during scanning. Strength and modulus approach their maximum values as the energy deposited exceeds the amount needed to fully melt the applied powder. Elongation‐at‐fracture does not reach its maximum until higher energy‐melt ratio. Performance of blends with reused powder matches that of virgin powder when blend composition is adjusted to a standard melt‐flow index. The volumetric energy density and the energy‐melt ratio are useful for correlating mechanical properties with multiple process parameters and material thermal properties.

This work presents the most extensive data to date on mechanical properties of nylon 12 (Duraform^®) as they relate to the full range of process parameters. These data show that mechanical performance correlates strongly with the volume energy density. In contrast to the area energy density (a.k.a. Andrews Number), this volumetric parameter includes the effect of varying layer thickness and can be related directly to the melting characteristics of the polymer material. Within the parameter range studied, this relationship allows adjustment of one scan parameter for improved speed or dimensional accuracy while ensuring good strength by an offsetting adjustment of another parameter. Such trade‐offs will be important in future manufacturing applications of the laser sintering process. Understanding the energy‐melt ratio provides insight into the relationship between scan conditions and the physics of powder melting and sintering, and offers a methodology to relate results at other bed temperatures and with other polymer powders.

The cement-filled PA12 manufactured by selective laser sintering (SLS) offers desirable mechanical properties; however, these properties are dependent on several fabrication parameters. As a result, SLS prototypes may exhibit orthotropic mechanical properties unless properly oriented in build chamber. This paper aims to evaluate the effects of part build orientation, laser energy and cement content on mechanical properties of cement-filled PA12.

The test specimens were fabricated by SLS using the “DTM Sinterstation 2000” system at which the specimens were aligned along six different orientations. The scanning speed was 914mm/s, scan spacing was 0.15mm, layer thickness was 0.1mm and laser power was 4.5–8Watt. A total of 270 tensile specimens, 270 flexural specimens and 135 compression specimens were manufactured and the tensile, compression and flexural properties of fabricated specimens were evaluated.

The experiments revealed orientation-dependent (orthotropic) mechanical properties of SLS cement-filled PA12 and confirmed that the parts with shorter scan vectors have enhanced flexural strength as compared with longer scan vectors. The maximum deviations of ultimate tensile strength, compressive strength and flexural modulus along the six orientations were 32%, 26% and 36%, respectively.

Although part build orientation is a key fabrication parameter, very little was found in open literature with contradictory findings about its effect on mechanical properties of fabricated parts. In this work, the effects of build orientation when combined with other fabrication parameters on the properties of SLS parts were evaluated along six different orientations.

The present paper aims to systematically investigate the influence of building orientations (0°, 15°, 30°, 45°, 60°, 75°) and heat treatment processes on the macro-/micro-structural, mechanical and electrochemical behaviors of selective laser melting (SLM) prepared AlSi10Mg alloy parts.

AlSi10Mg samples were produced by the SLM method using standard processing parameters at 0°, 15°, 30°, 45°, 60° and 75° building angles. The effects of building orientations on the physical, mechanical and electrochemical properties of the alloy were investigated.

With the increase in the building orientation from 15° to 75°, the structural defects were found reducing. The effect of step size of inclined geometries was found to significantly influence the mechanical and electrochemical properties of the AlSi10Mg samples. Tensile strength for samples fabricated at lower angles (0°, 15°, 30°) reported a drop of approximately 11% than SLM 0° samples. Moreover, the tensile strength was found to decrease from 412.35 ± 9.568 MPa for the as-built samples to 290.48 ± 12.658 MPa, whereas the fracture strain increases from 3.32 ± 0.56% to 5.6 ± 0.6% when the as-built sample was treated with T6 treatment. This study indicates that the microstructure and mechanical properties of SLM-processed AlSi10Mg alloy can be tailored by a suitable heat treatment or building angle.

Microstructural and mechanical behavior of horizontal or vertically built SLM components have already been demonstrated several times. However, the influence of different building orientations, such as 0°, 15°, 30°, 45°, 60°, 75°, has not been explored in-depth, particularly on corrosion and general mechanical performance. As a result, this work may be of significant relevance to academics and designers, given the varying orientation of internal component of SLM structures.