Sökning: "Jens Bergström"
Visar resultat 16 - 20 av 24 avhandlingar innehållade orden Jens Bergström.
16. Influence of microstructure on fatigue and ductility properties of tool steels
Sammanfattning : Fatigue and ductility properties in various tool steels, produced by powder metallurgy, spray forming or conventionally ingot casting, have been analysed experimentally and successfully compared to developed models. The models are able to predict the fatigue limit and cause for fatigue fracture, and strain- and stress-development until fracture during the ductile fracture process respectively. LÄS MER
17. Very high cycle fatigue of automotive steels : Testing and computation at 20 kHz
Sammanfattning : Mechanical fatigue failure occurs in components subjected to cyclic loading. A crack initiates at critical regions in the component and propagates during repeated loading. The expected fatigue life depends on the level, type and frequency of the loading. LÄS MER
18. On the Machinability of High Performance Tool Steels
Sammanfattning : The continuous development of hot forming tool steels has resulted in steels with improved mechanical properties. A change in alloying composition, primarily a decreased silicon content, makes them tougher and more wear resistant at elevated temperatures. However, it is at the expense of their machinability. LÄS MER
19. Chromium martensitic hot-work tool steels : damage, performance and microstructure
Sammanfattning : Chromium martensitic hot-work tool steel (AISI H13) is commonly used as die material in hot forming techniques such as die casting, hot rolling, extrusion and hot forging. They are developed to endure the severe conditions by high mechanical properties attained by a complex microstructure. LÄS MER
20. Very high cycle fatigue of duplex stainless steels and stress intensity calculations
Sammanfattning : Very high cycle fatigue (VHCF) is generally considered as the domain of fatigue lifetime beyond 10 million (107) load cycles. Few examples of structural components which are subjected to 107-109 load cycles during their service life are engine parts, turbine disks, railway axles and load-carrying parts of automobiles. LÄS MER