Magnesium alloy applications in automotive structures

The energy absorbed by magnesium alloys (high-pressure die-cast (HPDC) AM20, AM50, AM60, and extruded AZ31) in a buckling test was significantly greater than the aluminum alloy 6061 T6 and particularly mild steel of a similar weight, but was less than that of the aluminum alloy and steel for the same thickness (Figure 6).26 This indicates that mass savings can be achieved by the substitution with magnesium alloys to achieve similar energy-absorbing characteristics.

Haptically enabled interactive virtual reality prototype for general assembly

Desktop computers based virtual training systems are attracting paramount attention from manufacturing industries due to their potential advantages over the conventional training practices. Significant cost savings can be realized due to the shorter training-scenarios development times and reuse of existing engineering models. In addition, by using computer based virtual reality (VR) training systems, the time span from the product design to commercial production can be shortened due to non-reliance on hardware parts. Within the aforementioned conceptual framework, a haptically enabled interactive and immersive virtual reality (HIIVR) system is presented. Unlike existing VR systems, the presented idea tries to imitate real physical training scenarios by providing comprehensive user interaction, constrained within the physical limitations of the real world imposed by the haptics devices within the virtual environment. As a result, in contrast to the existing VR systems, capable of providing knowledge generally about assembly sequences only, the proposed system helps in procedural learning and procedural skill development as well, due to its high physically interactive nature.

Flux-assisted self-assembly of monodisperse colloids

We have developed a novel method to grow ordered layers of monodisperse colloids on a flat substrate. The evaporation of the colloidal suspension in the presence of the inclined substrate is strengthened by an external gas flux directed on the meniscus. The meniscus oscillations caused by the gas flux have an evident effect on the ordering of the spheres on the substrate. Thick films (more than 150 layers in a single-step deposition) of large area single crystals (1 cm2) can be obtained in a very short time (~1 cm/h maximum growth rate) and from very diluted suspensions (up to 0.022% volume fraction).

Towards development of a quality cost model for automotive stamping

The current work used discrete event simulation techniques to model the economics of quality within an actual automotive stamping plant. Automotive stamping is a complex, capital intensive process requiring part-specific tooling and specialised machinery. Quality control and quality improvement is difficult in the stamping environment due to the general lack of process understanding and the large number to interacting variables. These factors have prevented the widespread use of statistical process control. In this work, a model of the quality control techniques used at the Ford Geelong Stamping plant is developed and indirectly validated against results from production. To date, most discrete event models are of systems where the quality control process is clearly defined by the rules of statistical process control. However, the quality control technique used within the stamping plant is for the operator to perform a 100% visual inspection while unloading the finished panels. In the developed model, control is enacted after a cumulative count of defective items is observed, thereby approximating the operator who allows a number of defective panels to accumulate before resetting the line. Analysis of this model found that the cost sensitivity to inspection error is dependent upon the level of control and that the level of control determines line utilisation. Additional analysis of this model demonstrated that additional inspection processes would lead to more stable cost structures but these structures many not necessarily be lower cost. The model was subsequently applied to investigate the economics of quality improvement. The quality problem of panel blemishes, induced by slivers (small metal fragments), was chosen as a case stuffy. Errors of 20-30% were observed during direct validation of the cost model and it was concluded that the use of discrete event simulation models for applications requiring high accuracy would not be possible unless the production system was of low complexity. However, the model could be used to evaluate the sensitivity of input factors and investigating the effects of a number of potential improvement opportunities. Therefore, the research concluded that it is possible to use discrete event simulation to determine the quality economics of an actual stamping plant. However, limitations imposed by inability of the model to consider a number of external factors, such as continuous improvement, operator working conditions or wear and the lack of reliable quality data, result in low cost accuracy. Despite this, it still can be demonstrated that discrete event simulation has significant benefits over the alternate modelling methods.

Impact of electronic data interchange in the Australian automotive industry

Information technology continues to play an increasingly significant role in the development of firms competing in the vast array of markets from those classified as global markets, such as the automotive industry, to the smaller nationally-based markets such as retailing. An objective of electronic commerce is to assist organisations to remain competitive and gain entry to markets which were previously unattainable. This study focuses on the organisational impact of one form of electronic commerce (electronic data interchange) on the component sector of the Australian automotive industry and examines the extent to which trading partner relationships have been affected. The research investigates the extent to which the integration of electronic data interchange (EDI) with an organisation’s internal application system may facilitate specific net benefits. The automotive industry became the first Australian industry to cooperatively adopt EDI. Research to date has not adequately examined the organisational impact of the nature and extent of net benefits gained from EDI adoption. To achieve the objective of assessing EDI net benefits, a conceptual model was developed. The model proposed that the level of EDI net benefits expected is influenced by the size of the organisation and the concentration of trade achieved within the industry via intervening links through (a) the level of senior management commitment and (b) the extent of system integration. Nine empirically testable research propositions are derived from the model, each testing the relationship between model constructs. Data was collected from 114 component suppliers to Ford Australia in 1992 and 1994 using a repeated cross-sectional longitudinal design. Structural equation modelling using partial least squares was adopted in the analysis of the data. A pure longitudinal model together with 12 case studies of selected component manufacturers supplemented the research design. The results of the research showed that the proposed conceptual model is a good description of the data. In particular, net benefits obtained from EDI adoption are directly determined by the size of the organisation, and the extent to which firms integrate EDI into their internal application systems. The level of net benefits is only indirectly influenced by the level of senior management commitment to the EDI project through (a) management commitment’s direct effect on integration, and (b) the direct effect the volume of trade a supplier achieves with the automotive industry on senior management commitment and system integration. The major benefits organisations experienced from EDI were enhanced productivity, clerical staff savings, improved data accuracy, enhanced customer service and reduced administration costs. The research showed that few suppliers gained inventory savings from EDI, a frequently claimed benefit from EDI adoption. Evidence of small improvements in product quality emerged from the results. In summary, this research attempts to make two primary contributions to knowledge, first in providing a method by which net benefits from electronic commerce can be measured within an industry adopting electronic trading, and second, by providing organisations with the knowledge of the specific net benefits organisations could expect from EDI adoption, together with the four major factors affecting these benefits. The research concludes with possible directions for future research, in particular an assessment of the impact of incorporating financial EDI into electronic trading.

Effect of bake-hardening on the structure-property relationship of multiphase steels for the automotive industry

The effect of a bake-hardening (BH) treatment on the microstructure and mechanical properties has been studied in C-Mn-Si TRansformation Induced Plasticity (TRIP) and Dual Phase (DP) steels after: (i) thermomechanical processing (TMP) and (ii) intercritical annealing (IA). The steels were characterized using X-ray diffraction, transmission electron microscopy (TEM) and three-dimensional atom probe tomography (APT). All steels showed high BH response. however, the DP and trip steels after IA/BH showed the appearance of upper and lower yield points, while the stress-strain behavior of the trip steel after TMP/BH was still continuous. This was due to the higher volume fraction of bainite and more stable retained austenite in the TMP/BH steel, the formation of plastic deformation zones with high dislocation density around the "as-quenched” martensite and “TRIP” martensite in the IA/BH DP steel and IA/BH TRIP steel, respectively.