A novel approach of deposition for uniform diamond films on circular saw blades

Uniform diamond films are highly desirable for cutting industries, due to their high performance and long lifetime used on cutting tools. Nevertheless, they are difficult to obtain on cutting tools with complicated shapes, greatly limiting the applications of diamond films. In this study, a novel approach of deposition for uniform diamond films is proposed, on circular saw blades made of cemented carbide using reflectors of brass sheets. Diamond films are deposited using hot filament chemical vapor deposition（HFCVD）. A novel concave structure of brass sheets is designed and fabricated, improving the distribution of temperature field, and overcoming the disadvantages of the conventional HFCVD systems. This increases the energy efficiency of use without changing the structure and increasing the cost of HFCVD. The grains are refined and the intensities of diamond peaks are strengthened obviously, which is confirmed by scanning electron microscopy and Raman spectra respectively.

Advanced nonlinear rheology magnetorheological finishing: A review

High-performance devices usually have curved surfaces, requiring high accuracy of shape and low surface roughness. It is a challenge to achieve high accuracies for form and position on a device with low surface roughness. However, due to the unique nonlinear rheology, magnetorheological fluids with hard abrasives are widely applied in ultra-precision surface finishing. Compared with conventional mechanical finishing, magnetorheological finishing displays obviously advantages, such as high precision shape of machined surface, low surface roughness and subsurface damage, and easy control for finishing processes. However, finishing performance depends on various factors, e.g. volume fraction and distribution of magnetic particles, types of hard abrasives and additives, strength of magnetic field, finishing forms. Therefore, a comprehensive review on related works is essential to understand the state-of-the-art of magnetorheological finishing and beneficial to inspire researchers to develop lower cost, higher machining accuracy and efficient approaches and setups, which demonstrates a significant guidance for development of high-performance parts in fields of aerospace, navigation and clinical medicine etc. This review starts from the rheological property of magnetorheological fluids, summarizing dynamically nonlinear rheological properties and stable finishing approaches. Then, the effect of components in magnetorheological fluids is discussed on finishing performance, consisting of magnetic particles, carrier fluid, additives and abrasives. Reasonable configuration of magnetorheological fluids, and different magnetorheological finishing methods are presented for variously curved surfaces. In addition, the current finishing forms and future directions are also addressed in this review.

Geoprocessing in Cloud Computing platforms-a comparative analysis

The emergence of Cloud Computing technologies brings a new information infrastructure to users.Providing geoprocessing functions in Cloud Computing platforms can bring scalable,on-demand,and cost
effective geoprocessing services to geospatial users.This paper provides a comparative analysis of geoprocessing in Cloud Computing platforms
Microsoft Windows Azure and Google App Engine.The analysis compares differences in the data storage,architecture model,and development environment based on the experience to develop geoprocessing services in the two Cloud Computing platforms;emphasizes the importance of virtualization;recommends applications of hybrid geoprocessing Clouds,and suggests an interoperable solution on geoprocessing Cloud services.The comparison allows one to selectively utilize Cloud Computing platforms or hybrid Cloud pattern,once it is understood that the current development of geoprocessing Cloud services is restricted to specific Cloud Computing platforms with certain kinds of technologies.The performance evaluation is also performed over geoprocessing services deployed in public Cloud platforms.The tested services are developed using geoprocessing algorithms from different vendors,GeoSurf and Java Topology Suite.The evaluation results provide a valuable reference on providing elastic and cost-effective geoprocessing Cloud services.