Sökning: "constant-load"

Visar resultat 1 - 5 av 13 avhandlingar innehållade ordet constant-load.

1. 1. Thermal Cycling, Creep- and Tensile Testing of Cast Exhaust Materials at Elevated Temperatures

   Författare :Christian Öberg; Stefan Jonsson; Henrik Östling; KTH; []
   Nyckelord :creep; constant-load; thermal cycling; tensile test; cast materials; cast iron; exhaust materials.; Teknisk materialvetenskap; Materials Science and Engineering;

   Sammanfattning : An exhaust manifold of a truck engine is subjected to tough conditions. As the truck is started, operated and shut down, it becomes subjected to thermal cycling up to around 800°C. At such high temperatures, corrosion, fatigue and creep are active degradation mechanisms. LÄS MER

3. 2. Corrosion testing of heat exchanger tubing

   Författare :Ulf Kivisäkk; KTH; []
   Nyckelord :corrosion testing; heat exchanger; stainless steels; general corrosion; immersion testing; activation; stress corrosion cracking; constant load; u-bends; relaxation; dewpoint corrosion;

   Sammanfattning : Heat exchanger tubes are commonly made from stainless steel.In a heat exchanger both the process fluid and the cooling orheating media can be corrosive. It is therefore important to beable to select materials that do not suffer from corrosion.Current methods in this area, however, suffer from limitationsand shortcomings. LÄS MER

4. 3. Creep Behavior of High Temperature Cast Materials for Exhaust Applications

   Författare :Christian Öberg; Stefan Jonsson; Baohua Zhu; John Hald; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Creep; creep behaviour; creep damage; ductile cast iron; high-alloyed austenitic cast steel; thermal cycling; tensile testing; stress relaxation; oxidation; precipitation.; Teknisk materialvetenskap; Materials Science and Engineering;

   Sammanfattning : This thesis focuses on creep of four cast materials intended for exhaust manifolds in heavy-duty truck engines. Two of the materials are ferritic ductile cast irons, SiMo51 and SiMo1000, one is an austenitic ductile cast iron, D5S, and another one is an austenitic cast steel, HK30. LÄS MER

5. 4. Mechanical Behaviour of Wood Exposed to Humidity Variations

   Författare :Annika Mårtensson; Avdelningen för Konstruktionsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; KstrWood;

   Sammanfattning : The effects on wood of simultaneous mechanical and moisture loading are studied. In order to clarify the mechano-sorptive behaviour of wood, a review of different phenomena presented in the literature is included. Compressive tests have been performed on spruce. The tests have been performed with both constant load and varying load. LÄS MER

7. 5. Elastohydrodynamic lubrication under non-steady conditions

   Författare :Roland Larsson; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements;

   Sammanfattning : The six papers presented in this thesis consider the effects on elastohydrodynamic lubrication (ehl) of non-steady conditions. The vast majority of ehl investigations, both experiemental and theoretical, utilise steady state conditions, i.e. constant load, velocity, geometry and temperature. LÄS MER