Numerička simulacija popunjavanja gravure u procesu kovanja u otvorenom ukovnju

master's thesis

• Title (english): Numerical simulation of die filling in the process of die forging
• Author: Dominik Krog
• Mentor: Zdenka Keran (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2022-07-20, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Production Mechanical Engineering

Abstract

Deformacija materijala podrazumijeva promjenu oblika i dimenzija pod utjecajem sila. Dijeli se na plastičnu i elastičnu, a glavna razlika je u obliku materijala koji nastaje nakon prestanka djelovanja sile. Elastična deformacija podrazumijeva povratak materijala na početni oblik nakon prestanka djelovanja sile, dok kod plastične deformacije dolazi do trajne promjene oblika i materijal poprima novi oblik. Jedan od brojnih procesa kojima je cilj postići plastičnu deformaciju kako bi se postigao oblik upotrebljivog proizvoda, jest proces kovanja. Kovanje se dijeli na dva osnovna principa: slobodno kovanje i kovanje u ukovnju. Proces se izvodi na kovačkim strojevima koji se dijele na batove i preše. Osnovni zadatak tih strojeva je djelovati silom na obradak i tako ga plastično deformirati u željeni oblik.
Prilikom kovanja u ukovnju tečenje materijala je ograničeno gravurom ukovnja. Popunjavanje gravure važan je parametar. Kao posljedica lošeg popunjavanja može doći do raznih grešaka i problema u otkivku. Kako bi se to spriječilo razvijeni su softveri za simulaciju tečenja materijala. Na temelju podjele materijala na konačne elemente softver analizira svaki pojedinačni element volumena i nakon obrađenog procesa daje vizualizaciju tečenja materijala te raspodjelu naprezanja. U ovom radu korišten je softver Marc Mentat uz primjenu materijala 15Cr3, C15 i Al99,8. Prikazane su simulacije tečenja materijale te raspodjela naprezanja u uvjetima s i bez trenja.

Abstract (english)

Deformation of material means a change of the material in shape and dimensions under the impact of forces, which is divided into plastic and elastic deformation. The main difference between plastic and elastic deformation is in the form of the material formed after the removal of applied force. Elastic deformation implies the return of the material to its initial shape after the removal of initially applied force, whereas plastic deformation causes a permanent change in shape resulting in the material taking on a new shape.
One of the many processes aiming at achieving plastic deformation and therefore achieving a shape of a usable product is the forging process. Forging is divided into two basic principles: free forging and die forging. The process is performed on forging machines divided into hammers and presses. The primary task of these machines is to apply force to the workpiece and thus deform it plastically into the desired shape.
In the process of die forging, the flow of material is limited by the engraving of the die. Filling the engraving is an important parameter, considering that various errors and problems in the forging can occur as a result of poor filling. To prevent this, software for simulating the flow of materials has been developed. Based on the division of the material into their finite elements, the software analyzes each individual volume element and, after the finished process, provides a visualization of the material flow and the distribution of stresses. In this paper, Marc Mentat software with the applied materials 15Cr3, C15, and Al99.8 was used. Simulations of material flow and stress distribution in conditions with and without friction are shown.

• Keywords: kovanje; tečenje materijala; kovanje u ukovnju; naprezanje; numeričke simulacije
• Keywords (english): forging; material flow; die forging; stress; numerical simulations
• Language: croatian
• URN:NBN: urn:nbn:hr:235:650259
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-07-06 14:37:51