Application of computer simulation at optimization of technological parameters of precision die forging

Abstract

Original scientific paper The paper deals with the optimization of technological parameters of precision forging in closed die using computer simulation with the aim to achieve high dimensional accuracy and surface quality of drop forgings. The research has been applied on spur gears with a hub. This type of mechanical part has been chosen because of its wide application in machine industry. Shape of this drop forging is suitable for the precision forging technology, as well. Case hardening steel 16MnCr5 has been selected as a common material used for drop forging production. Computer simulation is a useful solution for prediction of the forging process development and material behaviour in closed die cavity. The numeric simulation has been used for the optimization of billet shape and dimensions and observation of plastic flow in closed die cavity at warm die forging. Suitability of material flow in die cavity, effective plastic strain and temperature of drop forging have been evaluated by means of simulation software Simufact.forming. To meet all requirements on accuracy of drop forgings it is necessary to take into consideration optimization of technological parameters using computer simulation.Keywords: closed die; computer simulation; forgeability; spur gear; precision warm die forging; upsetting test Primjena simulacije računalom u optimizaciji tehnoloških parametara kod preciznog kovanjaIzvorni znanstveni članak Rad se bavi optimizacijom tehnoloških parametara kod preciznog kovanja u zatvorenom kalupu primjenom simulacije računalom s ciljem postizanja visoke dimenzionalne točnosti i kvalitete površine otkivaka dobivenih kalupnim kovanjem. Istraživanje se provodilo na čelnicima s ravnim zubima s glavinom. Taj je tip strojnog dijela izabran zbog njegove široke primjene u strojarstvu. Oblik takvog otkivka također je pogodan za tehnologiju preciznog kovanja. Čelik za kaljenje 16MnCr5 odabran je kao materijal za proizvodnju kalupnim kovanjem. Simulacija računalom je korisno rješenje za predviđanje odvijanja postupka kovanja i ponašanja materijala u zatvorenoj šupljini kalupa. Numerička simulacije je primijenjena u optimizaciji oblika i dimenzija trupca te promatranja plastičnog tečenja u zatvorenoj šupljini kod kovanja u kalupu. Odgovarajući tok materijala u kalupu, učinkovita plastična deformacija i temperatura kalupnog kovanja procijenjeni su pomoću simulacijskog softvera Simufact.forming. Kako bi se zadovoljili svi zahtjevi vezani za točnost otkivaka dobivenih kalupnim kovanjem potrebno je uzeti u obzir optimizaciju tehnoloških parametara primjenom simulacije računalom. Ključne riječi:

Experimental Investigations of Induction Heating in Warm Forming of Stainless Steel Sheets

“…In austenitic stainless steel, martensite formation takes place, which is not only affected by temperature but also influenced by the rate at which the material is deformed. The temperature range concerning steel during warm metal forming processes is approximately 600 to 800 °C [6]. In comparison with the conventional sheet metal forming processes, warm forming requires an initial increasing of the blank temperature before the forming stage.…”