Vpliv lokalne ohlajevalne hitrosti na mikrostrukturo in napake tlačno ulitega ohišja vodne črpalke : diplomsko delo

Rudolf, Matic (author), Petrič, Mitja (mentor)

Diplomsko delo zajema primerjavo dveh različnih tehnologij izdelave gravurnih vložkov orodja za tlačno litje in vpliv le-teh na napake pri ohišju črpalke, ki so ulite s tem orodjem. Ohišje črpalke je ulito iz aluminijeve livne zlitine AlSi9Cu3, ki je ena najpogosteje uporabljenih zlitin pri postopku tlačnega litja. Vložki so izdelani z različnima tehnologijama izdelave, prvi po klasičnem postopku z vrtanjem in drugi s tehnologijo 3D tiskanja kovin. Razlikujejo se po položaju in obliki hladilnih kanalov, ki so del hladilno-grelnega sistema, s katerim se skrbi za ustrezno uravnavanje temperatur v orodju za tlačno litje. Dobro temperiranje orodja je ključno za izdelavo kakovostnih ulitkov in čim daljšo življenjsko dobo orodja. Krčilna poroznost je ena izmed najpogostejših napak pri procesu tlačnega litja. Po navadi se pojavlja na mestih v ulitku, ki so najbolj vroča in se strdijo zadnja, zato je na teh mestih ključnega pomena dobro temperiranje, da zagotovimo čim večji odvod toplote in preprečimo pojav krčilne poroznosti. Cilj diplomskega dela je bil ugotoviti kako obe različni vrsti gravurnih vložkov vplivata na temperaturno polje orodja za tlačno litje in na krčilno poroznost ohišja črpalke, ki je s tem orodjem ulito. Temperaturno polje orodja smo analizirali s termovizijsko kamero, ulitke pa z napravo za rentgensko analizo. Metalografsko analizo prerezov ulitka smo opravili s svetlobnim mikroskopom in avtomatskim stereo mikroskopom s polarizatorjem. Na podlagi rezultatov opravljenih analiz smo ugotovili, da z uporabo vložkov, izdelanih s tehnologijo 3D tiskanja kovin ulijemo ohišje črpalke z manjšo krčilno poroznostjo.

• Language: Slovenian
• Keywords: tlačno litje, hladilno-grelni sistem, krčilna poroznost, AlSi9Cu3, 3D tiskanje kovin
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Place of publishing: Ljubljana
• Publisher: [M. Rudolf]
• Year: 2022
• Number of pages: XI, 44 f.
• PID: 20.500.12556/RUL-138091
• UDC: 669
• COBISS.SI-ID: 127172099
• Publication date in RUL: 09.07.2022

RUDOLF, Matic, 2022, Vpliv lokalne ohlajevalne hitrosti na mikrostrukturo in napake tlačno ulitega ohišja vodne črpalke : diplomsko delo [online]. Bachelor’s thesis. Ljubljana : M. Rudolf. [Accessed 19 March 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=138091

Secondary language

• Language: English
• Title: Influence of local cooling rate on microstructure and defects of high pressure die-cast water pump housing : diploma work

Abstract

The diploma work includes a comparison of two different die inserts for die casting tools produced with different technologies and the impact of these on the defects in the pump housing, which is made with this tool. The pump housing is casted from AlSi9Cu3 aluminum casting alloy, which is one of the most commonly used alloys in the die casting process. The inserts are made with various manufacturing technologies, the first using the classic drilling process and the second with 3D metal printing technology. It differs in the position and shape of the cooling channels, which are part of the cooling-heating system with which the temperature in the die-casting tool is properly regulated. Good tool tempering is key to making quality castings and maximizing tool life. Shrinkage porosity is one of the most common defects in the die casting process. It usually occurs at the hottest parts of the casting and solidify last, so good tempering is crucial in these places to ensure maximum heat dissipation and prevent shrinkage porosity. The aim of the diploma work was to determine how different types of inserts affect the thermal field of the die casting tool and the shrinkage porosity of the pump housing, which is casted with this tool. The thermal field of the die was analyzed with a thermal imaging camera and the castings with an X-ray analysis device. Metallographic analysis of the cross-sections of the casting was performed with a light microscope and an automatic stereo microscope with a polarizer. Based on the results of the analyzes made, we concluded, that the pump housing is casted with lower shrinkage porosity when inserts are made by 3D metal printing technology.

• Keywords: high pressure die casting, cooling and heating system, shrinkage porosity, AlSi9Cu3, 3D printing