Sökning: "Surface resistance"

Visar resultat 1 - 5 av 715 avhandlingar innehållade orden Surface resistance.

1. 1. Challenges in Resistance Welding of Ultra High Strength Steels

   Författare :Erik Tolf; Arne Melander; Zuheir Barsoum; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Resistance welding; spot welding; surface cracks; nut welding; UHSS; projection welding; Teknisk materialvetenskap; Materials Science and Engineering;

   Sammanfattning : Increasing the use of Ultra High Strength Steels (UHSS) in vehicle bodystructures is important for reducing weight and cutting CO2 emissions. This thesis investigates challenges in resistance welding that can be a barrier to implementing UHSS as a replacement for low strength steels in vehicle structures. LÄS MER

3. 2. Localised corrosion and atmospheric corrosion of stainless steels

   Författare :Sukanya Hägg Mameng; Rachel Pettersson; Christopher Leygraf; Thomas Ladwein; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; stainless steel; localised corrosion; atmospheric corrosion; alloy composition; surface finish; surface roughness; surface treatment; surface orientation; contamination; chloride; sulphate; temperature; chlorination; exposure conditions.; Kemi; Chemistry;

   Sammanfattning : This research is focused on defining limiting conditions for corrosion of stainless steels. The aim of the first part (Papers I-IV) was to understand the role of alloying level and environmental parameters on localised corrosion in aqueous conditions. LÄS MER

4. 3. Tyre-road Interaction: a holistic approach to noise and rolling resistance

   Författare :Tiago Vieira; Sigurdur Erlingsson; Ulf Sandberg; Anders Genell; Hans Jonasson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pavement; surface; texture; noise; rolling resistance; tyre; Vägbeläggning; vägyta; textur; buller; rullmotstånd; däck; Byggvetenskap; Civil and Architectural Engineering;

   Sammanfattning : Energy dissipation, fuel consumption, real-estate property prices and health issues are some of the aspects related to the tyre/pavement interaction and its functional properties of rolling resistance and noise. The first two aspects are affected by the tyre/road interaction as energy is dissipated mostly by hysteretic losses as the tyre is subjected to dynamic deformations when contacting the pavement surface. LÄS MER

5. 4. Land surface heat exchange over snow and frozen soil

   Författare :David Gustafsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Surface energy balance; Snow; Boreal forest; SVAT models; Eddy-correlation Measurements; Latent heat flux; Sensible heat flux; Net radiation; Soil temperature; Aerodynamic roughness; Surface resistance; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur;

   Sammanfattning : The energy exchange in the soil-snow-vegetation-atmospheresystem was studied to improve the quantitative knowledge of thegoverning processes. The lack of such knowledge contributes tothe uncertainty in the applicability of many existing modelsindependent of the temporal or spatial scale. LÄS MER

7. 5. Tyre/road interaction : A holistic approach to the functional requirements of road surfaces regarding noise and rolling resistance

   Författare :Tiago Vieira; Sigurdur Erlingsson; Ulf Sandberg; Tony Parry; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Road; surface; noise; rolling resistance; tyre; mitigation; Vägbeläggning; vägyta; textur; buller; rullmotstånd; däck; Building Materials; Byggnadsmaterial;

   Sammanfattning : Increased fuel consumption, increased greenhouse gas emission, diminishing real-estate prices and increased health issues are some of  the negative effects on the climate, on the environment and on the society from tyre/road rolling resistance and noise. The first two aspects are affected by energy dissipation in the tyre/pavement contact and are related to rolling resistance. LÄS MER