Sökning: "corrosion product deposition"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden corrosion product deposition.

1. 1. Atmospheric corrosion of zinc-aluminum and copper-based alloys in chloride-rich environments : Microstructure, corrosion initiation, patina evolution and metal release

   Författare :Xian Zhang; Inger Odnevall Wallinder; Christofer Leygraf; Manuel Morcillo; KTH; []
   Nyckelord :atmospheric corrosion; chloride deposition; Zn-Al alloy coatings on steel microstructure; Cu sheet and Cu alloys; microstructure; corrosion initiation; corrosion product evolution; metal release; SEM; IRAS; CRM.; Kemi; Chemistry;

   Sammanfattning : Fundamental understanding of atmospheric corrosion mechanisms requires an in-depth understanding on the dynamic interaction between corrosive constituents and metal/alloy surfaces. This doctoral study comprises field and laboratory investigations that assess atmospheric corrosion and metal release processes for two different groups of alloys exposed in chloride-rich environments. LÄS MER

3. 2. FEM Modelling of Micro-galvanic Corrosion in Al Alloys Induced by Intermetallic Particles : Exploration of Chemical and Geometrical Effects

   Författare :Litao Yin; Jinshan Pan; Christopher Leygraf; Ying Jin; Herman Terryn; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Finite Element Method FEM ; Modelling; Micro-galvanic corrosion; Al alloy; corrosion product deposition; chemical factors; steric hindrance effect; Kemi; Chemistry;

   Sammanfattning : Localized corrosion, such as pitting, crevice corrosion or galvanic corrosion, is a long-standing phenomenon that can greatly limit the life of metallic materials. For decades experimental methods have been used to try to understand the underlying physical, chemical and electrochemical processes that control localized corrosion in order to find effective protection methods against its propagation. LÄS MER

4. 3. Quantified In Situ Analysis of Initial Atmospheric Corrosion : Surface heterogeneity, galvanic effects and corrosion product distribution on zinc, brass and Galvalume

   Författare :Ping Qiu; Christofer Leygraf; Béatrice Hannoyer; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Atmospheric corrosion; Zinc; Brass; Galvalume; In Situ; Quantification.; Materials science; Teknisk materialvetenskap;

   Sammanfattning : The interaction of the surface of a pure metal or an alloy with the surrounding atmosphere occurs in a highly complex interfacial regime. During atmospheric corrosion this interfacial regime involves the metal surface, often covered by a naturally formed oxide layer of a few nanometers thickness; an aqueous adlayer, typically with a thickness of a few to a few tens of nanometers, and the atmosphere from which airborne particles, oxygen, and gaseous pollutants dissolve into the adlayer and influence the atmospheric corrosion process. LÄS MER

5. 4. The role of particles on initial atmospheric corrosion of copper and zinc : lateral distribution, secondary spreading and CO2-/SO2-influence

   Författare :Zhuo Yuan Chen; Christofer Leygraf; Jan-Erik Svensson; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atmospheric corrosion; copper; zinc; NaCl particles; NH4 2SO4; Materials chemistry; Materialkemi;

   Sammanfattning : The role of sodium chloride (NaCl) particles and ammonium sulfate ((NH4)2SO4) particles on the initial atmospheric corrosion of copper and zinc was investigated under in situ and ex situ conditions using microgravimetry, FTIR spectroscopy, ion chromatography, scanning electron microscopy with x-ray microanalysis and the scanning Kelvin probe. For the first time, in situ infrared spectra were collected on a micron level during particle induced atmospheric corrosion using a recently developed experimental set-up for in situ FTIR microspectroscopy. LÄS MER

7. 5. Carbon Dioxide: The Unknown Factor in the Atmospheric Corrosion of Light Metals. A Laboratory Study

   Författare :Daniel Bengtsson Blücher; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SO2; temperature; CO2; atmospheric corrosion; magnesium; NO2; aluminum alloys; NaCl; O3; Mg-Al alloys;

   Sammanfattning : The atmospheric corrosion of Al and Mg-Al alloys was investigated using controlled air in the laboratory. The effects of CO2, temperature, NaCl, relative humidity, SO2, NO2 and O3 on corrosion rate and corrosion product composition were examined. LÄS MER