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|| [[attachment:2605SA1_coreloss.jpg | {{attachment:2605SA1_coreloss.jpg}}]] || Core loss appears proportional to (frequency × flux )^1.8^ . ]] || || [[attachment:2605SA1_coreloss.jpg | {{attachment:2605SA1_coreloss.jpg}}]] || Core loss appears proportional to <<BR>><<BR>> (frequency × flux )^1.8^ .<<BR>><<BR>> Figure from datasheet. ||

Rotor Lamination

Laminated launch loop rotors will have good magnetic properties and will rapidly disperse and oxidize in the atmosphere after a rotor-release catastrophe. Worst case, thin flakes survive and cut.

Metglas 2605SA1 looks good, higher temperature than 2605HB1M. datasheet downloaded 2017/02/11

Metglas 2605SA1

Curie temperature

395C / 668K

saturation induction

1.56 Tesla

thickness

23 μm

density

7.18 g/cm³

Thermal Expansion

7.6 ppm/°C

Iron vaporization temp

3140 K

Tensile Strength

1 GPa

Elastic Modulus

100 GPa

Iron

85 to 95%

IDLH Fe₂O₃

2.5g/m³

Silicon

5 to 10%

IDLH SiO₂

3.0g/m³

Boron

1 to 5%

IDLH B₂O₃

2,0g/m³

resistivity

1.3 μΩ-m

60 Hz and 1.4 T

Induction at 80 A/m

≥1.35 T

Core Loss

≤0.17 W/kg

Exciting Apparent Power*

1.1 (VA/kg)

attachment:2605SA1_coreloss.jpg

Core loss appears proportional to

(frequency × flux )1.8 .

Figure from datasheet.

Failure and oxidation

Iron has a specific heat of 25.1 J/(mol·K), vaporizes at 3140K, and has a heat of vaporization of 340 kJ/mol . Naively, to go from 400K to vaporization requires 410 kJ/mol or 16 MJ/kg . The rotor moves at 14 km/s, the kinetic energy is 98 MJ/kg, so there is more than enough energy to vaporize the rotor foil and ignite it. Further study and experimentation needed; perhaps most of the energy will end up in the surrounding air.

RotorLamination (last edited 2017-10-21 17:03:39 by KeithLofstrom)