ART
BEAUTY & WELLNESS
CRAFT
CULTURE & HISTORY
ENTERTAINMENT
ENVIRONMENT
FOOD & DRINKS
REVERSE ENGINEERING
SCIENCES
SPORTS
TECHNOLOGY
WEARABLES
Ferrite Toroid Core: Magnesium-Zinc Ferrite, One-Day Grind, 1400 °C (Snoek 1948, Ex. II)
A soft ferrite ring core of magnesium-zinc ferrite: magnesia, zinc oxide and iron oxide ground for a whole day, pressed into a ring and fired at 1400 °C in oxygen. Snoek's ring had an initial permeability of 670 and a Curie point near 100 °C.
Source: J. L. Snoek, US 2,452,530 (Philips, 1948), Example II. Unknown: the 'violet' iron oxide, linked to an unknown head. Picture: the patent's Fig. 4, the ring core.
Advanced
2 days
Instructions
1
1
Weigh 25.5 : 25.5 : 49 mol %
Weigh 25.5 : 25.5 : 49 mol %
Mix 25½ mol % pure magnesia, 25½ mol % pure zinc oxide and 49 mol % pure violet iron oxide. Ours, by weight: 9.4 g magnesium oxide, 18.99 g zinc oxide and 71.61 g iron oxide per 100 g. Unknown: what makes the iron oxide 'violet'.
Materials for this step:
Magnesium Oxide9.4 g
Zinc Oxide Powder18.99 g
Violet Iron Oxide71.61 gTools needed:
Balance Scale
Dust Mask2
2
Grind for one day in an iron ball mill
Grind for one day in an iron ball mill
Grind the mixture for one day in a mill with iron balls.
Tools needed:
Iron Ball MillDust Mask3
3
Press a ring at 4 tons per cm²
Press a ring at 4 tons per cm²
Press the powder at 4 tons per square centimetre into a ring 3 cm across with a 4 × 4 mm cross-section.
Tools needed:
Hydraulic Press
Ring Pressing DieDust Mask4
4
Fire 1 hour at 1400 °C, cool slowly in oxygen
Fire 1 hour at 1400 °C, cool slowly in oxygen
Heat the ring in oxygen for 1 hour at 1400 °C, then cool it slowly in oxygen. Snoek's ring had an initial permeability of 670 at room temperature and 2 kHz.
Tools needed:
Tube Furnace
Oxygen
Pressure Gas Cylinder
Pyrometer
Crucible Tongs
Heat-Resistant GlovesMaterials
3- 9.4 gPlaceholder
- 18.99 gPlaceholder
- 71.61 gPlaceholder
Tools Required
11- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
This blueprint makes
Related Blueprints
These blueprints share knowledge with this one — techniques, materials, or principles that connect them in the learning graph.
CC0 Public Domain
This blueprint is released under CC0. You are free to copy, modify, distribute, and use this work for any purpose, without asking permission.
Support the Maker by purchasing products through their Blueprint where they earn a Maker Commission set by Vendors, or create a new iteration of this Blueprint and include it as a connection in your own Blueprint to share revenue.