Comparative study on turning CI and CGI using silicon nitride cutting tools

There has been a great interest for improving the machining of cast iron materials in the automotive and other industries. Comparative studies for tool used to machine grey cast iron (CI) and compacted graphite iron (CGI) on dry machining were also performed in order to find out why in this case the tool lifetime is not significantly higher. However the machining these materials while considering turning with the traditional high-speed steel and carbide cutting tools present any disadvantages. One of these disadvantages is that all the traditional machining processes involve the cooling fluid to remove the heat generated on workpiece due to friction during cutting. This paper present a new generation of ceramic cutting tool exhibiting improved properties and important advances in machining CI and CGI. The tool performance was analyzed in function of flank wear, temperature and roughness, while can be observed that main effects were found for tool wear, were abrasion to CI and inter-diffusion of constituting elements between tool and CGI, causing crater. However the difference in tool lifetime can be explained by the formation of a MnS layer on the tool surface in the case of grey CI. This layer is missing in the case of CGI.

Cutting edge web

The artwork describes web as a network environment and a space where people are connected and as a result, it can reshape you as an interactive participant who is able to regenerate an object as a new form through a truly collaborative and cooperative interactions with others. The artwork has been created based on the research findings of characteristic of web: 1) Participatory (Slater 2002, p.536), 2) Communicational (Rheingold 1993), 3) Connected (Jordan 1999, 80), and 4) Stylising (Jordan 1999, 69). The artwork has conceptualised and visualised those characteristics of web based on principles of graphic design and visual communication.

Contribution of thickened drinks, food and enteral and parenteral fluids to fluid intake in hospitalised patients with dysphagia

Background Studies amongst older people with acute dysphagic stroke requiring thickened fluids have assessed fluid intakes from combinations of beverage, food, enteral and parenteral sources, but not all sources simultaneously. The study aimed to comprehensively assess total water intake from food, beverages, enteral and parenteral sources amongst dysphagic adult in-patients receiving thickened fluids. Methods Patients requiring thickened fluid following dysphagia diagnosis were recruited consecutively from a tertiary teaching hospital’s medical and neurosurgical wards. Fluid intake from food and beverages was assessed by wastage, direct observation and quantified from enteral and parenteral sources through clinical medical records. Results No patients achieved their calculated fluid requirements unless enteral or parenteral fluids were received. The mean daily fluid intake from food was greater than from beverages whether receiving diet alone (food 807±363mL, food and beverages 370±179mL, p<0.001) or diet with enteral or parenteral fluid support (food 455±408mL, food and beverages 263±232mL, p<0.001). Greater daily fluid intakes occurred when receiving enteral and parenteral fluid in addition to oral dietary intake, irrespective of age group, whether assistance was required, diagnosis and whether stage 3 or stage 2 thickened fluids were required (p<0.05). After enteral and parenteral sources, food provided the most important contribution to daily fluid intakes. Conclusions The greatest contribution to oral fluid intake was from food, not beverages. Designing menus and food services which promote and encourage the enjoyment of fluid dense foods, in contrast to thickened beverages, may present an important way to improve fluid intakes of those with dysphagia. Supplemental enteral or parenteral fluid may be necessary to achieve minimum calculated fluid requirements.

Theoretical analysis of serrated chip formation based on ideal models in high speed cutting

In this paper, two ideal formation models of serrated chips, the symmetric formation model and the unilateral right-angle formation model, have been established for the first time. Based on the ideal models and related adiabatic shear theory of serrated chip formation, the theoretical relationship among average tooth pitch, average tooth height and chip thickness are obtained. Further, the theoretical relation of the passivation coefficient of chip's sawtooth and the chip thickness compression ratio is deduced as well. The comparison between these theoretical prediction curves and experimental data shows good agreement, which well validates the robustness of the ideal chip formation models and the correctness of the theoretical deducing analysis. The proposed ideal models may have provided a simple but effective theoretical basis for succeeding research on serrated chip morphology. Finally, the influences of most principal cutting factors on serrated chip formation are discussed on the basis of a series of finite element simulation results for practical advices of controlling serrated chips in engineering application.