Authors:
Daniel Figueiredo (1,2), B. Guimarães (1,3), Tiago E.F. Silva (4), Cristina M. Fernandes (1), J. Paulo Davim (2)
1- R&D Department, Palbit S.A., Aveiro, Portugal
2- Department of Mechanical Engineering, University of Aveiro, Portugal.
3- Center for MicroElectroMechanical Systems, University of Minho, Guimarães, Portugal
4- INEGI, University of Porto, Porto, Portugal
Abstract:
Machining in ductile mode is usually applied for finishing precision parts of hard materials, such as cemented carbide parts, medical ceramic components or glass material applications. Thus, the study of ductile mode cutting of brittle materials has been attracting more and more efforts. The possibility of applying predominant plastic-flow cutting (ductile mode), using ultra-precision machines, in hard/brittle materials has been previously linked to the careful selection of operational conditions, regarding the brittle-to-ductile threshold. This threshold, also known as the critical depth of cut, relates with material specific properties (i.e., elastic modulus, material hardness and fracture toughness) as is widely employed in grinding processes control. In the present work, micro-milling of WC-15wt.%Co sintered samples was performed with diamond coated end mills, confirming the influence of a ductile-to-brittle threshold on the cutting regime. Critical scale effects and structure-related behaviour were also confirmed. A positive impact on machined surface quality was observed when ductile mode was applied. Scanning electron microscopy was used to evaluate the microstructure features after different machining conditions.
DOI:
https://doi.org/10.59499/EP246281747
