Potentials of precision machining processes for the manufacture of micro forming molds

Abstract

Molds for micro forming processes require specific functional surfaces to provide optimized tribological condition for forming processes. Such topographies with microscopic dimensions can for instance be generated by lithographical methods. However, a main disadvantage of these processes is their low flexibility, e.g. changing the structures to be generated causes extensive adaptations in the manufacturing process. Therefore, mechanical precision machining processes like micro milling, micro grinding and micro polishing are appropriate processes for the manufacture of micro molds of manifold shapes and with well suited micro topographies.

Advances in engineered surfaces for functional performance

“…Recent reviews of the state of the art on precision cutting processes for manufacturing micro-optical elements are reported in [28] and in [193]. Mechanical technologies however cannot manufacture certain optical microstructures such as V-shaped concave dots.…”

“…Masking methods Chemical texturing [46,79,154,192] Electrochemical texturing [58,229] Non-masking methods Self-assembling [25,46,120,211] Maskless laser assisted etching [161] Maskless electrochemical texturing [46,195] Anisotropic etching [94,183] Mechanical CNC ultrasonic machining [46] Mechanical honing [16,146] Grinding [174] Free abrasive machining [70,224] Microcutting [28,46,70,83,225] Patterned erosion [1,205] Fig. 17.…”

Micro metal injection molding (MicroMIM)

“…For a more detailed discussion of production methods see (Yang et al, 2009;Fu et al, 2010). Micro-machining and micro-discharge machining are currently the most popular and most established methods (Brinksmeier et al, 2008). Finally, two or more structuring methods can be combined to manufacture (Bergstrom et al, 2001;Schneider et al, 2005) describes experiments performed in special test stands, which compared mold insert materials according to their respective wear resistances.…”

Polymer micro molding with bulk metallic glass mold

“…at present, two kinds of methods are generally used in fabrication of micro structured mold insert or cavity. One is direct structuring methods, like mechanical machining, electric discharge machining (eDM) or laser structuring; and the other is the field of lithographic methods, like e-beam lithography, UVlithography, and for structures with high aspect ratio, X-ray lithography (Brinksmeier et al 2008). Mold materials are varied, with stainless steel, aluminum, silicon, nickel or a combination of different materials.…”