Vpliv deleža tekočekristalnega polimera na mehanske in magnetne lastnosti PPS-NdFeB brizganih plastomagnetov : magistrsko delo

Uršič, Ana (avtor), Karpe, Blaž (mentor), Šinkovec, Rok (komentor)

Plastomagneti so vrsta kompozitov, ki jih sestavljajo magnetni prahovi, polimerno vezivo in razni aditivi. Danes obstaja veliko vrst teh materialov, uporabljajo pa se na različnih področjih, še posebej pomembni so v avtomobilski industriji. Razvoj teh kompozitov stremi k izdelavi cenovno dostopnih materialov, s katerimi se lahko proizvaja izdelke kompleksnih oblik z visokimi dimenzijskimi tolerancami in ki so v primerjavi s sintranimi magneti enostavnejši za predelavo v končne oblike. Zaradi naštetih lastnosti kljub nekoliko nižjim magnetnim lastnostim vse bolj konkurirajo klasičnim sintranim trajnim magnetom. V sklopu magistrskega dela smo raziskovali, kako dodatek tekočekristalnega polimera (LCP) vpliva na mehanske in magnetne lastnosti plastomagnetnega materiala na osnovi NdFeB magnetnega prahu in polifenilen sulfidnega veziva (PPS). Testirali smo tudi štiri različne aditive, in sicer dva za izboljšanje kompatibilnosti med uporabljenima polimeroma ter dva za povečanje tekočnosti polimerom. S postopkom kompaundiranja in granuliranja smo izdelali serijo plastomagnetnih materialov, ki smo jim z dodajanjem različnih deležev tekočekristalnega polimera in aditivov spreminjali sestavo polimerne matrice. Deleža in sestave polnila iz NdFeB magnetnega prahu pri tem nismo spreminjali. Z injekcijskim brizganjem smo izdelali vzorce, na katerih smo izvedli meritve gostote in magnetnih lastnosti, natezni ter tritočkovni upogibni preizkus. Uporabljena polimera smo analizirali z diferenčno dinamično kalorimetrijo (DSC), na granulatih plastomagnetnih materialov pa smo določali indeks masnega pretoka (MFR). Na preizkušancih za določanje mehanskih lastnosti smo na koncu izvedli še metalografsko analizo. Rezultate meritev smo nato analizirali in primerjali med seboj predvsem z ozirom na osnovni material brez dodanega LCP in aditivov.

• Jezik: Slovenski jezik
• Ključne besede: NdFeB, PPS, tekočekristalni polimeri LCP, kompaundiranje, injekcijsko brizganje
• Vrsta gradiva: Magistrsko delo/naloga
• Tipologija: 2.09 - Magistrsko delo
• Organizacija: NTF - Naravoslovnotehniška fakulteta
• Kraj izida: Ljubljana
• Založnik: A. Uršič
• Leto izida: 2024
• Št. strani: XVI, 55 f.
• PID: 20.500.12556/RUL-158591
• UDK: 669
• COBISS.SI-ID: 200521475
• Datum objave v RUL: 16.06.2024

URŠIČ, Ana, 2024, Vpliv deleža tekočekristalnega polimera na mehanske in magnetne lastnosti PPS-NdFeB brizganih plastomagnetov : magistrsko delo [na spletu]. Magistrsko delo. Ljubljana : A. Uršič. [Dostopano 5 maj 2025]. Pridobljeno s: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=slv&id=158591

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Influence of liquid crystalline polymer content on mechanical and magnetic properties of PPS-NdFeB injection molded magnets : master's thesis

Izvleček

Plastomagnets are a type of composite consisting of magnetic powders, a polymeric binder, and various additives. Today, there are many types of these materials used in various fields, but they are particularly important in the automotive industry. The development of these composites aims to produce affordable materials for manufacturing products with complex shapes and high dimensional tolerances, and they are easier to process into final forms compared to sintered magnets. Due to these properties, despite having somewhat lower magnetic properties, they are increasingly competing with traditional sintered permanent magnets. As part of a master's thesis, we investigated how the addition of a liquid crystalline polymer (LCP) affects the mechanical and magnetic properties of a plastomagnetic material based on NdFeB magnetic powder and a polyphenylene sulfide (PPS) binder. We also tested four different additives: two to improve compatibility between the polymers used and two to increase polymer fluidity. Through compounding and granulation processes, we produced a series of plastomagnetic materials, altering the composition of the polymer matrix by adding various proportions of liquid crystalline polymer and additives. However, we did not alter the proportion and composition of the NdFeB magnetic powder. Using injection molding technology, we manufactured samples on which we performed density and magnetic properties measurements, as well as tensile and three-point bending tests. The polymers used were analyzed using differential scanning calorimetry (DSC), and the plastomagnetic granulates were analyzed for melt flow index (MFI). Finally, we conducted metallographic analysis on the specimens to determine their mechanical properties. The measurement results were analyzed and compared, primarily focusing on the base material without the addition of LCP and additives.

• Ključne besede: NdFeB, PPS, liquid crystal polymer LCP, compounding, injection molding