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Piezoelectric driven Micro-press for microforming

Presz W., Andersen B., Wanheim T.

Journal of Achievements in Materials and Manufacturing Engineering

2006

Vol. 18, nr 1-2

411--414

Purpose: Progressive miniaturisation generates necessity of micro-parts production also on the field of metal forming. At present small pats are produced with a big presses which were designed for manufacturing much bigger products. Further miniaturisation will not make possible to keep sufficient tolerances of products manufacturing with these standard presses. Design/methodology/approach: It is suggested to set up special technological lines for micro-parts production. Such lines would consist of micro-machines based on piezoelectric actuators. The recent development of that kind of actuators assures even up to several kilo-Newton forces and movement accuracy theoretically in atomic scale. As a step for building the line, a micro-press with piezoelectric drive is being constructed. Findings: The constructed press can work with direct actuator and can be also equipped with simple mechanical movement amplifier. Micro-indenting, micro-pressing and micro-backward extrusion were successfully carried on the press. Examples of simple sequentional and incremental micro-forming processes were also performed. Research limitations/implications: Equipping Micro-press with additional devices like x-y or x-y-z table positioning, automatic clamping and supplying systems etc. will able to extend its application to wide range of microforming processes. Practical implications: Micro-press in intention is going to be a part of industrial micro-lines for micro-product. Originality/value: The idea of building micro-parts with micro-machines standing as production micro-line seems to be quite natural but so far not realised. Presented Micro-press with original construction is another step to put this idea into reality.

Modelowanie fizyczne jako metoda weryfikacji obliczeń numerycznych

Presz W., Wanheim T.

Prace Naukowe Politechniki Warszawskiej. Mechanika

2003

z. 201

19--24

Przeprowadzono próby wyciskania współbieżnego w płaskim stanie odkształcenia dla różnych kątów matrycy, dwóch warunków tarcia i dwóch materiałów modelowych na bazie wosku. W ściankach matrycy umieszczono czujniki rejestrujące naciski w trakcie procesów. Wyniki porównano z obliczeniami numerycznymi w celu ich weryfikacji. Naciski uzyskane z eksperymentu były zgodne z obliczeniami tylko dla niskiego czynnika tarcia. W przypadku skrajnym niezgodność sięgała nawet 70%.

The test stand based on physical modeling technique has been comleted to validate results of FEM simulations mainly in the aspect of friction model. Plane strain forward extrusionswith different angles, different materials and different friction conditions have been carried outwith strain gagues membrane pressure sensors positioned on a side and top of die. Recorded pressure distribution on tool surface during deformation process has been used for evaluation of Commercial FEM package.