Ferrite Toroid Core: Copper-Zinc Ferrite Fired at 1050 °C, Held at 600 °C in Oxygen (Snoek)

Ferrite is a ceramic magnet: iron oxide combined with other metal oxides, carrying magnetic flux while hardly conducting electricity. Snoek at Philips (US 2,452,531, 1948) made this copper-zinc ferrite ring at a lower heat: technical copper oxide, zinc oxide and iron oxide with 1 % brownstone, fired at 1050 °C, then held 14 hours at 600 °C, all in oxygen. His ring had an initial permeability of 385. The picture: our diagram.

고급

2 days

안내

Mix 20.7 : 31.6 : 47.7 mol + 1 % brownstone

Mix technical copper oxide, zinc oxide and iron oxide in the molecular ratio 20.7 : 31.6 : 47.7 (on the pure oxides) and add 1 % by weight of brownstone (manganese dioxide). Ours, by weight: 13.91 g copper oxide, 21.73 g zinc oxide and 64.36 g ferric oxide per 100 g, plus 1 g brownstone.

이 단계의 재료:

산화 구리13.91 g

산화아연 분말21.73 g

산화제이철64.36 g

이산화망가니즈 (연망가니즈석)1 g

필요한 도구:

접시 저울

방진 마스크

Grind for 3 hours in an iron ball mill

Grind the mixture for 3 hours in a mill with iron balls.

필요한 도구:

철 볼 밀

방진 마스크

Mould a ring at 4 tons per cm²

Mould a ring 3 cm across and 4 × 4 mm in section at 4 tons per square centimetre, with water as the plastifying and binding agent.

필요한 도구:

유압 프레스

링 프레스 다이

증류수

Fire 1 hour at 1050 °C, hold 14 hours at 600 °C

Sinter the ring in oxygen at 1050 °C for 1 hour, cool it slowly to 600 °C and hold it there for 14 hours, all in oxygen, then let it cool further. Snoek's core had an initial permeability of 385.

필요한 도구: