Correlation between edge radius of the cBN cutting tool and surface quality in hard turning

In this study, the attempt has been made to investigate the correlation between the cutting tool edge radius and surface quality in terms of the surface roughness and subsurface deformation through a FE simulation and experiment. Machining tests under different machining conditions were also conducted and the surface roughness and subsurface deformation were measured. Surface roughness and subsurface deformation were produced by the cutting tools with different edge radii under various cutting parameters. Both results from the FE simulation and machining tests confirmed that there was a significant influence on the surface quality in terms of both the surface roughness and subsurface quality from the edge radius. There is a critical edge radius of cBN tools in hard turning in terms of surface quality generated.У даному дослідженні було зроблено спробу дослідити взаємозв’язок між радіусом закруглення крайки різального інструменту і якістю поверхні, які оцінюються шорсткістю поверхні і деформацією підповерхневого шару, методами скінчено-елементного моделювання і експериментально. Було здійснено низку експериментів при різних умовах обробки з одночасним вимірюванням шорсткості поверхні і деформації підповерхневих шарів. Також застосовували різальні інструменти з різними радіусами різальної крайки при різних режимах різання. Результати моделювання і випробувань підтвердили значний вплив радіуса закруглення крайки на якість і шорсткість поверхні, а також якість підповерхневого шару. Виявлено оптимальний радіус округлення крайки інструменту з КНБ, який треба застосовувати при обробці надтвердих матеріалів для отримання найкращої якості поверхні.В данном исследовании была сделана попытка изучить взаимосвязь между радиусом скругления кромки режущего инструмента и качеством поверхности, оцениваемой шероховатостью поверхности и деформацией подповерхностного слоя, методами конечно-элементного моделирования и экспериментально. Были проведены испытания при различных условиях обработки с одновременным измерением шероховатости поверхности и деформации подповерхностного слоя. Применялись режущие инструменты с различными радиусами режущей кромки при различных режимах резания. Результаты моделирования и испытаний подтвердили значительное влияние радиуса скругления кромки на шероховатость поверхности, а также на качество подповерхностного слоя. При точении закаленной стали инструментом из сBN имеется оптимальный радиус режущей кромки инструмента, который следует применять при обработке сверхтвердых материалов для получения наилучшего качества поверхности

Correlation between edge radius of the cBN cutting tool and surface quality in hard turning

cBN cutting tools with superior mechanical properties are widely used in machining various hard materials. The microgeometry of cBN cutting tools, such as the edge radius, has great influence on the surface quality of components and tool life. For optimized tool geometry, it is crucial to understand the influence of the cBN cutting tool microgeometry on the machined surface quality. In this study, the attempt has been made to investigate the correlation between the cutting tool edge radius and surface quality in terms of the surface roughness and subsurface deformation through a FE simulation and experiment. Machining tests under different machining conditions were also conducted and the surface roughness and subsurface deformation were measured. Surface roughness and subsurface deformation were produced by the cutting tools with different edge radii under various cutting parameters. Both results from the FE simulation and machining tests confirmed that there was a significant influence on the surface quality in terms of both the surface roughness and subsurface quality from the edge radius. There is a critical edge radius ofcBN tools in hard turning in terms of surface quality generated

Numerical and experimental investigation of tool geometry effect on residual stresses in orthogonal machining of Inconel 718

Residual stress has become more important than ever with the increasing performance requirement of components especially for those applied in safety-critical areas. As the machining process is fundamentally correlated with the acquired component properties, it is essential to fully understand the formation mechanism of residual stresses in the cutting process and its influence on the performance of the component. This paper presents results based on numerical and experimental analysis on the effect of tool geometry on thermal-mechanical load and residual stresses in orthogonal machining Inconel718 alloy. The Coupled Eulerian-Lagrangian (CEL) method is used to simulate the effect of tool geometry on temperatures, forces, equivalent plastic strains, and residual stresses. The local normal/tangential stress is introduced to determine the degree of the tensile plastic deformation induced by the tool. It is observed that a negative rake angle and a sharp edge radius tool tend to generate more compressive stress on the machined surface than the ones generated with positive rake angle tools and/or lager edge radius. Besides, an increase in flank wear produces less magnitude of compressive stress in subsurface due to a decreased local normal stress caused by increased flank contact length