3.3 Influence of substrate pretreatment on tribological properties of lubricating coatings Substrate surface pretreatment is an important factor affecting the tribological properties of bonded solid lubricating coatings. The corresponding treatment process should be selected according to different substrates. For non-metallic substrates, degreasing or sandblasting processes are usually used, as well as chemical pretreatment. For metal materials, in addition to the general derusting and degreasing processes, anodizing can be further applied to different metals. , chemical oxidation, electroplating, nitriding, sand blasting, vulcanization or phosphating. In the development of bonded solid lubricating coatings, the most basic work is the design and selection of the formulation, which includes: selecting the type of binder and lubricant according to the working conditions and performance requirements and the ratio between them; According to the interaction between various components and the law of synergistic effect, it is determined which composite lubricant solution and the suitable filler are used; the mixed solvent formulation is determined according to the solubility characteristics of the resin and the coating process requirements. The use of manual test screening method to determine the formulation requires a large number of combined design and selection, and the test workload is extremely large. To this end, based on the results of basic research and applied research on solid lubricant coatings in recent years, we have summarized the above various factors and their effects on coating properties into several mathematical models, such as oil adsorption theory of solid lubricant particles. The close packing model of the particles in the organic resin binder (Fig. 8), the solubility parameter principle of the mixed solvent selection, and the moderate principle of the equilibrium of the volatilization speed, etc., and then the optimal calculation formula of the coating is obtained by computer aided design, and finally the calculation is performed. The formulation was tested to determine the optimum coating formulation. The results of research on epoxy and phenolic resin-bonded solid lubricating coatings show that the computer-aided design formula is very close to the experimentally determined optimal formulation, and can significantly shorten the formulation development cycle, saving a lot of manpower and material resources, showing important Promotion value. Previous Next Luan Jinyu Metal Printing & Can Co., Ltd. , http://www.chmoreusage.com
Degreasing is an important part of the surface pretreatment process. The quality of the treatment is directly related to the adhesion of the coating to the substrate and other pretreatment steps. The degreasing methods usually used include alkali washing, pickling, solvent washing, emulsion washing, and electrolytic degreasing. One or two methods may be selected according to specific conditions, and the principle of washing is adopted.
For the same metal substrate, different pretreatment processes have different effects on the tribological properties of bonded solid lubricant coatings. Japan’s Ito Yuyi has conducted a detailed investigation of this aspect (2), and Figure 7 shows The wear-resisting life of the bonded solid lubricating coating after different surface treatments is obvious. The effect of sandblasting + phosphating is the best, followed by sandblasting, and the worst by grinding; for the same pretreatment The process and the roughness of the treated surface also have an important influence. Experience has shown that in the case of sand blasting, fine sand with a particle size of 76 μm or less should be used for the hard substrate, and for the soft substrate, the grain should be used. The coarse sand treatment with a diameter of about 150 μm is better; for phosphating, different phosphating series, and different crystal sizes in the same series have an important influence on the tribological properties of the bonded solid lubricating coating, such as The 45th steel substrate is almost doubled by the fine-grained manganese phosphate treatment than the coarse-grained treatment. The effect of the columnar fine-crystal manganese phosphating treatment on improving the wear resistance of the bonded solid lubricating film Best.
3.3 Computer Aided Design of Bonded Solid Lubricating Coating Formulation 