Study of integrated milling-grinding of microlens array on binderless tungsten carbide with diamond grains ball-end tool.

The hardness and brittleness of binderless tungsten carbide, make it difficult to fabricate microlens array (MLA) on it. In this paper, an integrated milling-grinding machining method was used to fabricate MLA on binderless tungsten carbide. A model for predicting the relationship between surface roughness and undeformed chip thickness during the integrated milling-grinding process was proposed. Microgroove machining experiments confirmed the relationship between surface roughness and undeformed chip thickness, which showed that the ductile-brittle transition boundary was divided. Based on this, an MLA was fabricated in the ductile mode, and the surface roughness of a single lenslet was approximately 16 nm. This integrated milling-grinding machining method is shown to be available for fabricating MLAs on hard substrates. • It is hard to fabricate microlens array on binderless tungsten carbide, integrated milling-grinding is proposed. • The integrated milling-grinding contains milling of the tool edge and grinding of the diamond grains. • Microgroove machining experiments validates the relationship between surface roughness and undeformed chip thickness. • Lenslets with high surface quality and little tool wear are obtained after machining microlens array. [ABSTRACT FROM AUTHOR]