OBRABOTKAMETALLOV Vol. 23 No. 3 2021 MATERIAL SCIENCE EQUIPMENT. INSTRUMENTS 6 1 4 the required amount of annular gear material was placed in the mold, pressing was performed with fi nal vulcanization. The general view of the two-teeth hone element is shown in fi gure 7, a. When trying to cut off a tooth fragment (end part) with a diamond cutting wheel, the abrasive layer separated from the annular gear material (fi gure 7, b). a b Fig. 7. Two-tooth fragment of a hone after vulcanization (a) and a view of the end part of a hone tooth with prevulcanized abrasive layer (b) The duration of partial vulcanization was reduced by 1.5 and 2.0 times to increase the adhesion strength. The adhesion strength increased, however, with the application of force, and the abrasive layer separated. In this regard, further studies were carried out without preliminary vulcanization of the functional layer. In the left part of the photograph (fi gure 8) there is a functional layer containing grinding powder of green silicon carbide 63C with a grain size of 28/20, with the annular gear material with the addition of aluminum powder in the right part. The interface of the two-layer specimen is homogeneous, without integrity violations, which ensures the necessary strength of adhesion. An experimental mold for the manufacture of a hone model with a 6 mm module, with a number of teeth of 14, was designed and manufactured. The necessary equipment for obtaining gear hone by hot injection molding was selected and manufactured. For preliminary studies, instead of diamond powder, green silicon carbide of the same grain size was used. As a result of the introduction of an additional amount of vulcanizing agents, the following Shore hardness values were obtained: the abrasive layer was 95 units, the annular gear material was about 90 units. The hone model was successfully tested during trial honing of a gear wheel with a diameter of 114 mm and a height of 32 mm. Honing of gear wheels in production conditions is carried out using kerosene-oil cooling lubricants. In this regard, the infl uence of this cooling lubricant on the hone material was investigated. It was found that after 7 days of exposure of hone in a kerosene-oil medium, the hardness of the functional surface of the abrasive layer and the annular gear material did not change. The hone was cut perpendicular to the axis to analyze the condition of the interface between the abrasive layer and the annular gear material. The morphology of the cross-sectional surface of the hone tooth was studied using optical and electron microscopes. The interface of the section (fi gure 9, a) is visually detected. There is a decrease in the thickness of the abrasive layer from the top of the hone tooth to its stem. Fig. 8. Interface between the abrasive layer and the annular gear material
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