Sökning: "VHCF"

Hittade 3 uppsatser innehållade ordet VHCF.

  1. 1. Life and fracture in very high cycle fatigue of a high strength steel

    Master-uppsats, Karlstads universitet/Institutionen för ingenjörsvetenskap och fysik (from 2013)

    Författare :Daniel Karlsson; [2021]
    Nyckelord :Very high cycle fatigue; VHCF; Fractography; Fine granular area; FGA; High strength tool steel; Ultrasonic testing equipment;

    Sammanfattning : Classical fatigue models teach that there is an intrinsic fatigue limit for steels, representing a level of stress that is too low for regular crack growth where every cyclic load propagates a fatigue crack through the material. Modern application with extreme lifetimes has shown that fatigue will still take place in steels with stress levels well below the expected fatigue limit. LÄS MER

  3. 2. Extremvärdesanalys (SEV) av högkvalitativt verktygsstål : Uppskattning av maximal inneslutningsstorlek i pulverstål

    Kandidat-uppsats, Karlstads universitet/Fakulteten för hälsa, natur- och teknikvetenskap (from 2013)

    Författare :Emil Pernefur; [2017]
    Nyckelord :Material science; Inclusions; Metallurgy; Tool steel; Powder steel; Extreme values analysis; SEV; Ultrasonic fatigue; VHCF; SS 11 11 16; Light-optical microscope; Scanning electron microscope; Materialteknik; Inneslutningar; Metallurgi; Verktygsstål; Pulverstål; Extremvärdesanalys; Ultraljudsutmattning; SS 11 11 16; Ljusoptiskt mikroskop; Svepelektronmikroskop;

    Sammanfattning : This work were requested by Uddeholms AB. Uddeholm is the worldś leading manufacturer of high performance tool steel for industrial tools. The company exists worldwide and is present in over 100 countries. One of the company’s main production processes is manufacturing powder steels with extremely high quality. LÄS MER

  4. 3. Wear mark evolution and numerical study of impact stresses in stainless steel flapper valves

    Master-uppsats, KTH/Materialvetenskap

    Författare :Jesper Larsson; [2016]
    Nyckelord :Flapper valve; FEM; Impact fatigue; Wear mark;

    Sammanfattning : Compressors that are used in refrigerators and air conditioners usually have flapper vales made of martensitic stainless steel to control the flow of the refrigerant in the system. During service the flapper valves are affected by both bending and impact fatigue in the very high cycle fatigue (VHCF) range with billions of cycles until failure. LÄS MER