Sökning: "Hot cracks"
Visar resultat 1 - 5 av 39 avhandlingar innehållade orden Hot cracks.
1. Closed-die forging and slab hot rolling with focus on material yield : some industrial problems analysed by FEM
Sammanfattning : The thesis is focussed on improving the material yield in closed-die forging and rolling. The former is restricted to the manufacturing of heavy crown wheels and front axle beams and the latter to the hot rolling of steel slabs. To enhance the yield the commercial FE-codes Form2D and Dyna3D are used. 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 : Hot cracking during solidification is a severe problem inmany casting processes, for example in continuous casting.Combinations of low strength and low ductility of the materialat high temperatures and applied tensile stress can cause hotcracking. LÄS MER
Sammanfattning : Delamination and spallation of thermal barrier coating (TBC) systems, used in hot parts of gas turbines, have been studied with respect to thermal fatigue. TBCs with and without pre-existing cracks were investigated. Thermal shock tests were performed until coating spallation. LÄS MER
Sammanfattning : The appealing properties of ceramics include retention of strength and hardness at high temperatures, chemical inertness and low density. However, monolithic ceramics fail in a brittle, unpredictable manner making them unsuitable for many applications where reliability is a key requirement. LÄS MER