Novel performance assessment of interrupted grinding process using aluminum oxide wheel with resinoid bond

• Autor(a) principal: Ribeiro, Fernando Sabino Fonteque
• Data de Publicação: 2021
• Outros Autores: Lopes, José Claudio [UNESP], Rodriguez, Rafael Lemes [UNESP], de Angelo Sanchez, Luiz Eduardo [UNESP], de Mello, Hamilton José [UNESP], de Aguiar, Paulo Roberto [UNESP], Bianchi, Eduardo Carlos
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1007/s00170-021-07757-1; http://hdl.handle.net/11449/229317
• topic: AISI 4340; Discontinuous grinding; External cylindrical grinding process; Number of grooves; Resinoid aluminum oxide wheel; Surface integrity; Wheel wear cost

The grinding of interrupted geometries, such as keyways, holes, lubrication channels and crankshafts, bearings, helical drills, sharpening, and gear hobbing process for pre-toothing, presents technical difficulties such as decrease in surface quality and an increase in costs, when compared to continuous grinding process. This work aims to study further findings about interrupted cylindrical grinding process of AISI 4340 steel, with the application of resinoid aluminum oxide grinding wheel and conventional application of MWF. In a novel and innovative way, this work analyzed the wheel wear cost at 3 different feed rates (0.25, 0.50, and 0.75 mm/min) for continuous workpieces and interrupted workpieces with 2, 6, and 12 grooves. In addition, surface roughness, roundness deviation, grinding power, tangential force, microstructural analysis, diametrical wear, and G ratio were also evaluated. In conclusion to the results obtained, the average values of surface roughness Ra and Rz increased with the severity of the process (feed rate and number of grooves). For feed rates varying from 0.25 to 0.75 mm/min, mean values of 0.51 to 1.10 μm (Ra) and 4.52 to 10.99 μm (Rz) were obtained for the condition with 12 interruptions, indicating an increase in the order of 75 to 114% compared to without interrupted workpiece. The quick wear of the wheel, obtained for an average diametrical wheel wear of 5.79 μm for workpiece with 12 interruptions in 0.75 mm/min, produced higher surface roughness values. Variations of more than 80% in roundness deviation were obtained during grinding at feed rates of 0.75 mm/min due to mechanical shocks during material removal process, being observed in force variations from 50 to 700 N. The cost analysis of grinding wheel wear showed the waste of abrasive material for grinding process with interrupted geometries. For all tests, the tool cost for low feed rate (0.25 mm/min) did not suffer great variations. For feed rates of 0.50 and 0.75 mm/min, the cost of tool wear was higher. The condition with the highest percentage increase in cost was recorded for grinding process with workpiece of 12 grooves and feed rate of 0.75 mm/min, generating an increase of up to 1720% in the tool cost. Converting into monetary values, the wheel cost is of $ 12.62 per 1000-piece batch.