| This experiment aims to develop a suitable wear-resistant coating used between the engine parts, which mainly reduced the coefficient of friction. The coating will not only increases the reliability of engine parts and provides corrosion protection to the components. Such coating is unlike other protective layer to enhance wear resistance through the isolation of mutual friction surface. Subsequently, the wear-resistant coating can provide lifelong lubrication for the majority of components.First, the solubility parameter of epoxy resin6101was calculated by the group contribution method, which was similar to the value found in literature. According to the similar polymer solubility parameter compatibility principle, intrinsic viscosity value of epoxy resin6101was measured in different solvent by Ubbelohde viscometer. The plot was drawn based on the solubility of epoxy resin6101in different solvents and the intrinsic viscosity of its corresponding solvent. Taking the toxicity, price, volatility of the solvent into considerations, butyl acetate was determined as the most suitable solvent of epoxy resin.Secondly, combined with TG, DTA measuring results, adhesion, hardness, heat resistance and other properties of wear-resistant coating were measured through a series of single factor experiments. A preferred formulation of silane-modified epoxy resin was determined including the kind and amount of the silicone, the content of deionized water, the catalyst dibutyl tin laurate, reaction time and temperature.Then, the influence of graphite and molybdenum disulfide filler on wear resistance, heat resistance of the coating was studied through the single factor experiment. The results showed that graphite and molybdenum disulfide has good synergies. Using in a certain proportion of the two can effectively improve the wear resistance of the coating, which manifested by the reduced wear weightlessness and friction coefficient. At the same time, adding the coating a certain amount of antimony trioxide can effectively enhance the hardness of the coating, and improve the wear resistance.Finally,5kinds of curing agents were used respectively on the modified epoxy resin for the curing reaction. The curing agent system were divinyl three amine, m-phenylenediamine, initiator DMP-30/polyamide650, phenolic modified amine and diamino diphenyl thiamphenicol DDS.Experimental research showed that curing system DMP-30/polyamide650achieved best heat resistant performance, which proved by the fact that mass loss rate hardness and adhesion changed least after320℃and450℃heat tests. Fuel resistance, acid, alkali and salt resistance of DMP-30/polyamide650and phenolic modified amine curing agents systems were relatively better than other curing agents. According to the coating curing kinetics analysis results, the apparent activation energy of initiator DMP-30/polyamide650curing system was the lowest, and reaction rate equation was K=8.606×106exp (7958.3/T)(1-a)0.871, which implied that the reaction rate was fast even at low temperature. DMP-30/polyamide650was the most suitable room temperature curing agent for organic silicone modified epoxy resins coating regarding the comprehensive performances. |
PDF Full Text Request