Sökning: "Staffan Jacobson"

Visar resultat 21 - 25 av 26 avhandlingar innehållade orden Staffan Jacobson.

1. 21. Silicon nitride for total hip replacements

   Författare :Maria Pettersson; Cecilia Persson; Håkan Engqvist; Staffan Jacobson; Kenneth Holmberg; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SiNx; Si3N4; coatings; CoCr; Ti; alloy; tribology; wear; corrosion; dissolution; debris; hip; arthroplasty; Teknisk fysik med inriktning mot materialvetenskap; Engineering Science with specialization in Materials Science;

   Sammanfattning : For more than 50 years total hip replacements have been a common and successful procedure to increase patient mobility and quality of life. The 10-year implant survival rate is 97.8%. LÄS MER

3. 22. Surfaces Designed for High and Low Friction

   Författare :Ulrika Pettersson; Staffan Jacobson; Roland Larsson; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; tribology; friction; surface texture; surface design; low friction; high friction; boundary lubrication; DLC; embossing; Materialvetenskap; Materials science; Teknisk materialvetenskap;

   Sammanfattning : This thesis comprises tribological studies of extremely well-defined surfaces of different designs. Both low-friction and high-friction surfaces were manufactured and experimentally evaluated.In the low-friction studies, lithography and anisotropic etching of silicon was first used as a texturing technique. LÄS MER

4. 23. Investigation of Topography, Adhesion and Diffusion Wear in Sliding Contacts during Steel and Titanium Alloy Machining

   Författare :Sara Saketi; Staffan Jacobson; Mikael Olsson; Pavel Krakhmalev; Uppsala universitet; []
   Nyckelord :Tribology; Metal cutting; Cemented carbide; PCBN; CVD and PVD coatings; Sur-face topography; Wear mechanisms; Diffusion;

   Sammanfattning : The aim of the present thesis work is to increase the fundamental knowledge of the tribological contact between the cutting tool and the work material in three different cutting operations, i.e. hard milling of cold work tool steels, turning in 316L stainless steel and turning in Ti6Al4V alloy, respectively. LÄS MER

5. 24. Formation and Function of Low-Friction Tribofilms

   Författare :Harald Skiöld Nyberg; Staffan Jacobson; Allan Matthews; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; tribology; tribofilm; PVD; coating; low-friction; tungsten disulphide; transition metal dichalcogenide; tribochemistry; Teknisk fysik med inriktning mot tribomaterial; Engineering Science with specialization in Tribo Materials;

   Sammanfattning : The use of low-friction coatings on machine elements is steadily increasing, and they are expected to play an important role in the reduction of fuel consumption of future motorized vehicles. Many low-friction coatings function by transformation of the outermost coating layer into tribofilms, which then cover the coating surface and its counter surface. LÄS MER

7. 25. On tool steel, surface preparation, contact geometry and wear in sheet metal forming

   Författare :Fredrik W. Lindvall; Jens Bergström; Staffan Jacobson; Karlstads universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wear; Galling; sheet metal; deep drawing; Tool steel; surface preparation; Friction; Materialteknik; Materials Engineering;

   Sammanfattning : In sheet metal forming operations the life length of the production equipment islargely dependent on the wear of the tools that are in direct contact with the sheet.One form of adhesive wear where some sheet material gets transferred to the tool, alsoknown as galling, is the most common cause of tool failure. LÄS MER