Winding a strong electromagnet

[capthook]

BTW, have you achieved any result with 1006?

The 1006 showed little noticable difference compared with the 1018 with my small coil, small input and limited testing accuracy.
I think to achieve a noticable difference would require laminated silicon steel, pure iron or an exotic and expensive nickel alloy like fully annealed Carpenter High Permeability "49"® Alloy or the HIPERCO 50.

(http://www.eaglealloys.com/c-8-nickel-iron-alloys.aspx is a possible source of alloys I haven't contacted)

[capthook]

Best contact I've found yet (after about 20 calls and 40 hrs of research)

http://www.hightempmetals.com/index.php

Very helpful and many types of products of many different sizes in stock.

PERMENDUR 2V
(HIPERCO ALLOY 50A)
(cobalt alloy - high permeability, highest flux density)

1/2" x 3' : $7.06 per inch
$20 cut charge
$25 packing charge

$298.00

HY MU 80 ROUND BAR
1/4" - 2 1/2" diameter rods
(nickel alloy:  highest permeability, high flux density)
Initial : 50,000u
Max: 200,000u
(currently on order)

All products should then be fully annealed.

If you wanted the best of the best - the HY MU 80 offers super-high permeability and would be an excellent choice........

[Xaverius]

Thought I would add this here as equations can get lost in the shuffle and might not be easily 'translated':

Question: I want to duplicate the 2000 Gauss strength in an electromagnet with a 3/4 inch diameter, 2 inch length solid metal core.

Answer:
A rough approximation:

(1) H in Oersted= (.4 x 3.14 x N x I)/coil length in cm

(2) B in Gauss = (H x (core permeability x 0.00000125664)) x 10000

So if 2,000 Gauss needed with core permeability of 800u:

H= 2000/10.05312 = 199
(rearrangement of  (2))

H = (.4 x 3.14 x N x I) / 5.08 = 199

N x I = (199 x 5.08) / 1.256 = 805 ampturns

So you could use:

N x I = 805 turns x 1 amp = 805 ampturns

805 turns of #22 AWG = 8.3 ohms
I=V/R : 9volts / 8.3 ohms ~ 1

So 805 turns of #22 AWG at 9 volts on a 800u permeability core (1010 steel) will achieve a rough approximation of around 2000 Gauss.

I think you mean 3/16" diameter core which is .4m.

(1) H in AT/m=NxI/length

(2) B in Tesla=H x (.000001256 x 800)

2000 Gauss=.2Tesla  ur=.0010048
.2/.0010048=199 AT/m

H=N x I/5.08    199 x 5.08=1011 AT

So you could use:
N x I=1011 x 1 amp=1011T

1011 turns of 22 gauge wire @ .4 x pi=106 feet  which yields 1.7 ohms

I=V/R    I=1  R=1.7  V=1.7  W=1.7

1011 turns of 22 gauge wire at 1.7V will yield 2000 gauss at 800 ur

[Xaverius]

The 1006 showed little noticable difference compared with the 1018 with my small coil, small input and limited testing accuracy.
I think to achieve a noticable difference would require laminated silicon steel, pure iron or an exotic and expensive nickel alloy like fully annealed Carpenter High Permeability "49"® Alloy or the HIPERCO 50.

(http://www.eaglealloys.com/c-8-nickel-iron-alloys.aspx is a possible source of alloys I haven't contacted)

Have you tried 1018 already?

[capthook]

Yes.
1006, 1018, Grade 2 hex bolt, Grade 5 hex bolt

All seemed similiar with my limited tests.
I have recently read several places that without a proper annealing, you might see a 3% increase between the 1006 and the 1018.....
I put out 3 RFQ's for annealing, haven't heard back...... hard to find a resource (like everything else  ) that deals in small quantities.