Optimizacija brizganja polipropilena ojačanega s steklenimi vlakni z metodo načrtovanja eksperimentov

Glinšek, Rok (author), Pepelnjak, Tomaž (mentor)

Namen magistrskega dela je bila raziskava vpliva procesnih parametrov injekcijskega brizganja na natezno trdnost izdelka. Spremljani parametri so bili temperatura taline, temperatura orodja, hitrost brizganja, naknadni tlak, čas naknadnega tlaka in čas hlajenja. Uporabljen je bil material polipropilen, ki je bil ojačan s 25 % steklenih vlaken. Eksperiment smo zasnovali po Taguchijevi metodi načrtovanja eksperimentov, kar je omogočilo sistematično proučevanje vpliva različnih parametrov na končni izdelek. Sledilo je brizganje epruvet, primernih za natezni preizkus, in izvedba nateznega preizkusa, s katerim smo določili natezno trdnost brizganih izdelkov. Rezultati analize so pokazali, da ima temperatura taline najvišji vpliv na natezno trdnost – višja temperatura taline znižuje natezno trdnost. Po drugi strani pa daljši čas naknadnega tlaka povečuje natezno trdnost izdelka. Optimalni vrednosti za hitrost brizganja in čas hlajenja za doseganje najvišje natezne trdnosti sta bili v srednjem območju. Temperatura orodja in naknadni tlak nista imela pomembnega vpliva na natezno trdnost. Po končani analizi rezultatov je sledil še potrditveni test, ki je služil za preverjanje ugotovitev iz eksperimentalnega dela.

• Language: Slovenian
• Keywords: brizganje polimerov, metoda načrtovanja eksperimentov, polipropilen, natezni preizkus, optimizacija procesa, Taguchijeva ortogonalna matrika
• Work type: Master's thesis/paper
• Organization: FS - Faculty of Mechanical Engineering
• Year: 2024
• PID: 20.500.12556/RUL-160354
• Publication date in RUL: 27.08.2024

Secondary language

• Language: English
• Title: Optimisation of injection moulding of glass fibre reinforced polypropylene using design of experiments method

Abstract

The purpose of this master's thesis was to investigate the influence of injection molding process parameters on the tensile strength of the product. The monitored parameters were melt temperature, mold temperature, injection speed, holding pressure, holding time, and cooling time. The material used was polypropylene reinforced with 25% glass fibers. The experiment was designed using the Taguchi method of experimental design, which allowed for a systematic study of the influence of different parameters on the final product. This was followed by the injection molding of specimens suitable for tensile testing, and the execution of the tensile test, through which we determined the tensile strength of the molded parts. The analysis results showed that melt temperature had the highest influence on tensile strength – higher melt temperatures decreased tensile strength. On the other hand, a longer holding time increased the tensile strength of the part. The optimal values for injection speed and cooling time to achieve the highest tensile strength were in the middle range. Mold temperature and holding pressure did not have a significant impact on tensile strength. After the analysis, a confirmation test was conducted to validate the findings from the experimental work.

• Keywords: injection molding, Design of experiments method, polypropylene, tensile test, process optimization, Taguchi orthogonal array