Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
INFLUENCE OF TOOL WEAR ON THE ROUGHNESS OF SPROWN SHAFTS GENERATED BY THE HOBBING PROCESS
Submission Author:
Carlos Eduardo Borsoi Rheinheimer Carlos , RS , Brazil
Co-Authors:
Carlos Eduardo Borsoi Rheinheimer Carlos, André João de Souza, Rodrigo Zeilmann
Presenter: Carlos Eduardo Borsoi Rheinheimer Carlos
doi://10.26678/ABCM.COBEM2023.COB2023-0558
Abstract
The hob is the most used machining process in gear manufacturing, generating all gear surfaces in a single process. The roughness of the involute profile of the gear tooth is highly relevant for engineering, as it directly influences the coefficient of friction generated in the sliding of the involute surfaces during gearing, generating more heat, higher noise levels, speed oscillations, loss of precision and efficiency of the transmission system. In addition, it directly impacts the life of gears by increasing tooth wear. Thus, the present work evaluates the influence of maximum flank wear (VBmax) of hobs coated with three different types of PVD coatings (TiN, TiAlN, and CrAlN) on the surface roughness of splined shafts manufactured by hobbing in SAE 8620 hardened steel, seeking a correlation of roughness values with each type of coating used. It was noted that there is a tendency for increasing roughness values as tool wear increases until it reaches a critical point (with VBmax close to 0.1 mm). Next, there is a tendency for decreasing roughness values, probably due to an increased tool tip radius. It was also observed that the TiN-coated tool showed the highest values of hob wear and splined shaft tooth roughness, the TiAlN-coated tool showed the lowest values of hob wear, and the CrAlN-coated tool, even with intermediate wear, showed the lowest roughness values of the splined shaft tooth. The CrAlN-coating also showed the most stability throughout the entire process and minor mean deviations. An evaluation of the textures of the splined shafts was also made, where the abrasive marks were found, more present when the hob with a less hardened coating was used (wear of 0.07 mm or less), in addition to attrition marks equally distributed in the cutting direction of the tool, where the CrAlN-coated tool produced these marks in smaller amounts and dimensions.
Keywords
Hobbing, Wear, Tool coating
