Surface chemistry and extreme pressure lubricant additive properties of chloroform on iron
| Autor: | L. Huezo, C. Crumer, Wilfred T. Tysoe, P.V. Kotvis, C. Soto |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
Langmuir
Chloroform Thermal decomposition Inorganic chemistry General Physics and Astronomy Halide chemistry.chemical_element Surfaces and Interfaces General Chemistry Condensed Matter Physics Chloride Surfaces Coatings and Films chemistry.chemical_compound chemistry medicine Chlorine Melting point Carbon medicine.drug |
| Zdroj: | Applied Surface Science. 78:113-122 |
| ISSN: | 0169-4332 |
| DOI: | 10.1016/0169-4332(94)90039-6 |
| Popis: | The growth kinetics and composition of films formed by the thermal decomposition of chloroform are very similar to those for methylene chloride reported previously [P.V. Kotvis et al., Wear 147 (1991) 401; 153 (1992) 305; Appl. Surf. Sci. 40 (1989) 213; Langmuir 9 (1993) 467], both depositing films that consist of an iron halide and incorporating carbon. Raman spectroscopy suggests that less carbon is incorporated into the layer grown from chloroform, an effect that is proposed to reflect the initial carbon : chlorine ratio in the precursor reactants. The tribological properties measured using a pin and V-block apparatus from the seizure load as a function of the additive concentration are very similar in both cases, showing an initial increase in seizure load up to additive concentrations of ≈ 2 wt% of chlorine and remaining constant thereafter, the main difference being that the saturation seizure load is higher when using chloroform than when methylene chloride is the additive. This effect is explained since the interfacial coefficient of friction of films grown from chloroform are lower than those from methylene chloride so that, for a particular applied load, the interfacial temperature is lower in the former case. Since the seizure load in the plateau region (at high additive concentrations) corresponds to the load at which the interface reaches the melting point of FeCl2, this temperature is attained at a higher load with CHCl3 than CH2Cl2. It is possible that the amount of carbon incorporated into the iron halide anti-seizure film affects the resulting coefficient of friction. |
| Databáze: | OpenAIRE |
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