ART
BEAUTY & WELLNESS
CRAFT
CULTURE & HISTORY
ENTERTAINMENT
ENVIRONMENT
FOOD & DRINKS
REVERSE ENGINEERING
SCIENCES
SPORTS
TECHNOLOGY
WEARABLES
Barium-Strontium Ferrite Disc Magnet: 0.09 mol BaCO3, 0.21 mol SrCO3, 1300 °C (Went, Philips 1956, Ex. 31)
A ceramic magnet with both barium and strontium: 0.09 mol barium carbonate and 0.21 mol strontium carbonate to 2.7 mol iron oxide, milled as in Example 28, pressed and passed through a 1300 °C furnace in 10 minutes. Went's rod held 1,340 gauss with a coercive force of 2,640 oersted.
Source: J. J. Went, G. W. van Oosterhout and E. W. Gorter (Philips), US 2,762,777 (1956), Example 31. They sintered rods; discs and the magnetising are ours. Picture: ferrite magnets, Omegatron, Wikimedia Commons, CC BY-SA 3.0.
Advanced
2 days
Instructions
1
1
Weigh the carbonates and iron oxide
Weigh the carbonates and iron oxide
Weigh 17.9 g barium carbonate (0.09 mol), 31.0 g strontium carbonate (0.21 mol), 435.5 g ferric oxide (2.7 mol). Barium carbonate is poisonous if swallowed: gloves and a dust respirator.
Materials for this step:
Barium Carbonate (Witherite)17.9 g
Strontium Carbonate31 g
Ferric Oxide435.5 gTools needed:
Balance Scale
Rubber Gloves
P100 Respirator2
2
Mill with alcohol 15 hours, dry
Mill with alcohol 15 hours, dry
As in Example 28: grind the mixture with alcohol in a ball mill for 15 hours, then dry it.
Tools needed:
Iron Ball Mill
Ethanol - Lab Grade, 95%
Drying Oven3
3
Press the powder
Press the powder
Example 28 moulds a rod without giving the pressure. Ours: press discs at 1.5 tonnes per cm², the pressure of the patent's other examples.
Tools needed:
Hydraulic Press
Disc Pressing Die4
4
Pass through a 1300 °C zone in 10 minutes
Pass through a 1300 °C zone in 10 minutes
Sinter in air at 1300 °C by passing the pieces through a 10 cm hot zone at 10 mm per minute: 10 minutes in the heat.
Tools needed:
Tube Furnace
Heat-Resistant Gloves5
5
Magnetise the discs
Magnetise the discs
The patent gives no magnetising method. Ours: lay a disc with its faces against the poles of a strong electromagnet, switch the current on, then off. Find which face is north with a compass.
Tools needed:
Electromagnet
CompassMaterials
3- Placeholder
- Placeholder
- 435.5 gPlaceholder
Tools Required
12- Placeholder
- 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.