Search for dissertations about: "melt stirring"

Showing result 1 - 5 of 9 swedish dissertations containing the words melt stirring.

2. 1. Mechanical properties of semi-solid Al castings : Role of stirring

   Author : Qing Zhang; Anders E.W. Jarfors; Stefan Jonsson; Tomas Liljenfors; Arne K. Dahle; Johan Ahlström; Jönköping University; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rheometal™ process; aluminum alloys; stirring; segregation; porosity; oxides; ductility; fatigue performance; melt quality;

   Abstract : Aluminum castings have been widely used in the automotive industry to reduce the vehicle's weight. However, the existence of casting defects significantly limits its application. The most common and detrimental defects in aluminum castings are porosity and oxides. READ MORE

4. 2. Some aspects of convection as well as graphite and carbide formations during casting

   Author : Fareed Ashraf Khan; Michael Vynnycky; Pär Jönsson; Bo Rogberg; Hasse Fredriksson; Jessica Elfsberg; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; carbides; heat treatment; cast iron; ball bearing steel; casting; cooling rate; structure analysis; nodule distribution; melt stirring; nuclei; karbider; värmebehanding; gjutjärn; kullagerstål; gjutning; kylningshastighet; strukturanalys; nodulefördelning; smältrörelse; kärnor.; Metallurgical process science; Metallurgisk processvetenskap;

   Abstract : It is an established fact that segregation during casting affects the physical properties of carbon-based ferro alloys; this motivates the study of the segregation behaviour of carbon and carbide-forming solute elements. In this context, this thesis investigates two different situations: the effects of cooling rate and turbulence on the precipitation behaviour of the graphite nodules in nodular cast iron; the nature of carbide precipitation in a bearing steel grade and the effects of subsequent soaking on these carbides. READ MORE

5. 3. Study of Non-metallic Inclusion in Alloy 825

   Author : Hans Kellner; Andrey Karasev; Pär Jönsson; Guozhu Ye; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Alloy 825; FeTi70R alloy; non-metallic inclusions; inclusion distribution; clusters; electromagnetic and gas stirring; ladle treatment; electrolytic extraction; stirring directions; Alloy 825; FeTi70R legering; icke-metalliska inneslutningar; inneslutnings fördelning; kluster; elektromagnetisk och gas omrörning; skänkugnsbehandling; elektrolytisk extraktion; omrörningshåll; Metallurgical process science; Metallurgisk processvetenskap; Steel Forming and Surface Engineering;

   Abstract : It is well known that inclusions affect the properties of steels and alloys. Therefore, it is important to understand what type of inclusions that exist and how they behave and especially with a focus on large size inclusions. READ MORE

6. 4. Numerical Study of the Gas Flow and Heat Transfer during Electromagnetic Stirring and Post Combustion in EAFs

   Author : Niloofar Arzpeyma; Pär Jönsson; Dongyuan Sheng; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; EMS; EAF; post combustion; heat transfer; duct system;

   Abstract : The effect of electromagnetic stirring on scrap melting and post combustion in two different electric arc furnaces (EAFs) have been studied using numerical modelling. The effect of electromagnetic stirring on melting of a piece of scrap located at the eccentric bottom tapping (EBT) region of an EAF has been studied. READ MORE

7. 5. Model Developments to Study Some Aspects of Improving Efficiencies in EAF Plants

   Author : Niloofar Arzpeyma; Mikael Ersson; Lauri Holappa; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : The aim of this thesis is to investigate some aspects of improvements with respect to the energy consumption and raw material selection as well as the understanding of the influence of uncertainties on the performance in electric arc furnace (EAF) plants. The effect of electromagnetic stirring on the scrap melting and post combustion capacity are investigated in two EAFs by using computation fluid dynamic (CFD) models. READ MORE