The effect of cutting parameters on surface integrity in milling TI6AL4V

CITATION: Oosthuizen, T., et al. 2016. The effect of cutting parameters on surface integrity in milling TI6AL4V. South African Journal of Industrial Engineering, 27(3):115-123, doi:10.7166/27-4-1199.The original publication is available at http://sajie.journals.ac.zaThe objective of machining performance is to reduce operational costs and to increase the production rate while maintaining or improving the required surface integrity of the machined component. Together with industrial partners, several benchmark titanium components were selected and machined to achieve this. Titanium alloys are used extensively in several industries due to its unique strength-to-weight ratio and corrosion resistance. Its properties, however, also make it susceptible to surface integrity damage during machining operations. The research objectives of this study were to understand the effect of cutting parameters on surface integrity to ensure that machined components are within the required surface quality tolerances. The effect of cutting speed and feed rate on surface roughness, micro-hardness, and the microstructure of the work piece were studied for milling Ti6Al4V. The surface roughness increased with a greater feed rate and a decrease in cutting speed. The maximum micro-hardness was 23 per cent harder than the bulk material. Plastic deformation and grain rotation below the machined surface were found with the rotation of the grain lines in the direction of feed. There was no evidence of subsurface defects for any of the cutting conditions tested.AFRIKAANSE OPSOMMING: Die masjineringsvermoë doelwit bly steeds om operasionele kostes te verminder en om die produksietempo te verhoog, terwyl die vereiste oppervlakafwerking van die komponent gehandhaaf of verbeter word. Ten einde hierdie doelstelling te bereik is verskeie komponente in samewerking met industrievennote, as maatstaaf komponente gekies en gemasjineer. Titaan allooie word op groot skaal in verskeie industrieë gebruik vanweë sy unieke sterkte-tot-digtheid verhouding en korrosiebestandheid. Hierdie eienskappe maak die allooi egter ook vatbaar vir oppervlakafwerking skade tydens die masjineringsproses. Die navorsingsdoelstelling van hierdie studie was om die effek van die snyparameters op die oppervlakafwerking te verstaan, om sodoende te verseker dat die komponente binne die vereiste oppervlak toleransies vervaardig word. Die effek van snyspoed en voertempo tydens freeswerk op die oppervlak grofheid, mikrohardheid en mikrostruktuur van die Ti6Al4V werkstuk is bestudeer. Die oppervlakgrofheid het verhoog met ’n toename in voertempo en vermindering in snyspoed. Die maksimum mikrohardheid was 23 persent harder as die basismateriaal. Plastiese vervorming en korrel rotasie onder die gemasjineerde werkstuk oppervlak is gevind met die korrelgrein in die rigting van die voer. Daar was geen aanduiding van sub-oppervlak defekte onder enige van die toets kondisies nie.http://sajie.journals.ac.za/pub/article/view/1199Publisher's versio