Visar resultat 1 - 5 av 72 avhandlingar innehållade ordet Superalloys.
Sammanfattning : Gas turbines are widely used in industry for power generation and as a power source at hard to reach locations where other possibilities for electrical power supplies are insufficient. New ways of producing greener energy is needed to reduce emission levels. This can be achieved by increasing the combustion temperature of gas turbines. LÄS MER
Sammanfattning : Usable weldability data is desired in the manufacturing industry, especially within the aerospace industry where fabrication of structural jet engine components are realized. Welding of precipitation hardening superalloys such as Waspaloy®, Alloy 718, ATI® 718Plus™ and Haynes® 282® in particular can lead to solidification cracking in the fusion zone, liquation cracking in the heat affected zone and/or to solid state cracking. LÄS MER
Sammanfattning : Abstract Grain boundary weaknesses of nickel-based superalloys not only materialize during service in the hot turbine engine sections but also during the weld manufacturing. The performance, in this respect, of the most commonly used alloys at Volvo Aero Corporation (VAC), 718 and the higher temperature capacity Waspaloy, are therefore the main subjects for this thesis. LÄS MER
Sammanfattning : Precipitation hardened Ni- and Ni-Fe- based superalloys, used in hot structural components for aero engines, are subjected to hot cracking phenomena during manufacturing and specifically in welding. This type of cracking involves metallurgical reactions from the liquid phase in concomitance to weld restraints. LÄS MER
5. On the Effect of Grain Size and Hardness on the Machinability of Superalloys and Chip Deformation
Sammanfattning : Superalloys are used in applications such as gas turbines, steam power plants and nuclear power systems that require good high temperature properties and/or exceptional corrosion resistance. Superalloys are classified as materials that are “difficult to machine”. In production machining is a most commonly occurring procedure. LÄS MER