Sökning: "prior austenite grains"

Hittade 3 uppsatser innehållade orden prior austenite grains.

  1. 1. Austenite grain growth in bearing steels : An investigation on steel grades 100Cr6 and 100 CRMnMoSi8-4-6

    Master-uppsats, KTH/Materialvetenskap

    Författare :Erik Persson; [2014]
    Nyckelord :Grain growth; Grain size;

    Sammanfattning : An investigation of austenite grain growth of two bearing steel grades; 100Cr6 and100CrMnMoSi8-4-6 is performed. Austenitization treatments were performed between 860°C and 1200 °C for 5 minutes to 5 hours and the grain size was determined for each sample.Grain boundary etching was carried out using a water based, picric-acid etchant. LÄS MER

  3. 2. Development of a heat treatment method to form a duplex microstructure of lower bainite and martensite in AISI 4140 stee

    Master-uppsats, KTH/Materialvetenskap

    Författare :Erik Claesson; [2014]
    Nyckelord :AISI 4140; 326C; 326F; Isothermal heat treatment; Martensite; Bainite; Molten salt; vacuum furnace; gas quenching.;

    Sammanfattning : Research on bainite and martensite structures has indicated that lower bainite needles have a refining effect on the lath martensitic structure. Lower bainte needles partitions prior austenite grains and will consequently have a refining effect on the subsequent formed lath martensite. LÄS MER

  4. 3. The effect of prior austenite grain size on the machinability of a pre-hardened mold steel. : Measurement of average grain size using experimental methods and empirical models.

    Master-uppsats, Avdelningen för maskin- och materialteknik

    Författare :Muhammad Aatif Irshad; [2011]
    Nyckelord :prior austenite grain size; machining; mold steels; pre-hardened mold steels; work hardening; retained austenite; metallography; tool steels; chemical etching; prior austenite grains; lath martensite; rough machining; finish machining; Metallographic specimen preparation; Austenite grain growth; cutting tool; cutting tool life; wear; Theoretical average chip thickness;

    Sammanfattning : The use of pre-hardened mold steels has increased appreciably over the years; more than 80% of the plastic mold steels are used in pre-hardened condition. These steels are delivered to the customer in finished state i.e. there is no need of any post treatment. LÄS MER