Sökning: "Surface Finish"
Visar resultat 16 - 20 av 53 avhandlingar innehållade orden Surface Finish.
16. Optimisation of Machining Operations by means of Finite Element Method and Tailored Experiments
Sammanfattning : Traditionally, costly experimental procedures have been followed in industry to optimise the machining operations to secure the maximum efficiency in production line, while the functional requirements of the machined surfaces are fulfilled. In recent years, development of robust numerical techniques such as Finite Element Method (FEM) and advances in computing capacity of computers have made it possible to simulate the machining operations under operational conditions. LÄS MER
17. Ionic lubricants : Molecular features and surface protection mechanisms
Sammanfattning : In this thesis ionic liquids (ILs) are investigated as prospective candidates for lubrication. Three custom synthesized phosphonium orthoborate type ILs were extensively studied from the prospective of molecular structuring both in bulk and at the interface and from the prospective of their lubricating performance as neat lubricants and as additives in oils. LÄS MER
18. Tribology in Metal Working
Sammanfattning : This thesis focuses on the tribological performance of tool surfaces in two steel working operations, namely wire drawing and hot rolling. In all forming operations dimensions and surface finish of the products are of utmost importance. LÄS MER
19. Towards functional characterisation for cylinder liner surfaces
Sammanfattning : The demands on decreased environmental impact from vehicles force the automotive industry to develop engines with reduced engine oil and fuel consumption. Frictional losses in the piston ring cylinder liner system accounts for approximately 20 % of the total frictional losses within an engine. LÄS MER
20. Chatter stability of turning and milling with process damping
Sammanfattning : The prediction of chatter instability in machining steel and thermal-resistant alloys at low cutting speeds has been difficult due to unknown process damping contributed by the contact mechanism between tool flank and wavy surface finish. This thesis presents modeling and measurement of process damping coefficients, and the prediction of chatter stability limits for turning and milling operations at low cutting speeds. LÄS MER