Spreminjanje lastnosti magnetnega prahu samarij-kobalt ob obdelavi

Vesel, Anže (author), Kozlevčar, Bojan (mentor)

Obdeloval sem odpadni magnetni material, nastali pri brušenju magnetov na osnovi Sm2Co17. Iz deležev suhega vzorca lahko sklepam na prisotnost Sm2(Co,Fe,Cu,Zr)13,8. Osnovnemu vzorcu sem odstranil večje nečistoče, ga posušil, dal v kalup, stisnil (z namagnetenjem in brez) ter sintral na 800-1000 °C. Osnovni vzorec pripravljen izven polja pokaže magnetizacijo 0,44 T, tisti v njem pa 0,51 T, kar je primerljivo z lastnostmi industrijskih magnetov Sm2Co17. Po drugi strani izdelan magnet brez uporabe zunanjega magnetnega polja pokaže magnetizacijo 0,40 T in 0,41 T z njegovo uporabo. Ta lastnost pa ni trajna, saj produkt popolnoma izgubi magnetni značaj v času enega dneva. Verjetni vzrok za hitro izgubo magnetnih lastnosti v obdelanem vzorcu je v neželeni prisotnosti kisika (w ~ 0,05), ki se veže na vzorec ob brušenju, s čimer se tvorijo oksidi in se posledično prekinejo medkovinske povezave.

• Language: Slovenian
• Keywords: recikliranje, magnetizem, trajni magneti, lantanoidi, SPS
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Year: 2019
• PID: 20.500.12556/RUL-111452
• COBISS.SI-ID: 1538449091
• Publication date in RUL: 01.10.2019

Secondary language

• Language: English
• Title: Samarium-cobalt magnetic powder properties changing during processing

Abstract

A residual magnetic material due to the grinding of Sm2Co17 based magnets was processed. Sm2(Co,Fe,Cu,Zr)13,8 metal ratio may be deduced from the elemental analysis of the dry sample. Mayor impurities were removed from the starting material, than it was dried, molded, compressed (with or without magnetization) and sintering at 800 1000 °C. The initial powder shows magnetization of 0,44 T, while the processed one in the external magnetic field shows 0,51 T, which is comparable to magnetic properties of the industrial Sm2Co17 magnets. On the other hand, the prepared magnet without applied external magnetic field shows magnetization 0,40 T, while if applied it shows 0,41 T. This capacity is however not lasting, as the magnetization completely disappears within a day. Probable reason for early disappearance of the processed sample magnetic properties lays in additional oxygen presence (w ~ 0,05), bound to the sample at grinding, enabling formation of oxides, consequently disabling direct metal-metal bondings.

• Keywords: recycling, magnetism, permanent magnets, lanthanides, SPS