The conflict is that the B-H curves for all three of those materials indicate that the MUr at 13,000 A/m should be 200 to 250, yet you're saying it should be closer to 10. That's a huge error. Why is the data off by that much? It makes the data useless.
Thanks for the information. Yeah, right now our material core specification calls out QQ-S-637, which is a Cold Finish spec. I would assume cold finishing without annealing would substantially reduce permeability.
Do you mean 10? 100 only brings it down by half.
I've heard about that upper limit of 1.6T. I wonder why the data/result is off by that much in that region?
Does anyone have any quantitative data on how annealing affects permeability for low carbon steels? Perhaps some B-H curves before and after annealing? I'd like to get an idea of how much is to be gained by annealing.
Ok, I got it now, my apologies. My problem was I was mixing units. Funny, the answer was staring at me in face when the calculation came out 165Oe and I measured 165G, Ha! Couldn't ask for a better empirical confirmation.
The only part I need clarification is calculating the B field with the...
Yes, I would have to agree with israelkk. My calculation would have been more realistic if I were modeling it after a toroid (closed circuit), but I do not have a toroidal solenoid so the calculation is not valid.
I did manage to measure the B field within the empty solenoid with a probe and it...
Excellent explanation, thanks!
Ok, so my coil parameters are as follows:
Coil Length (L): 17mm
Core Diameter (D): 4.75mm
# of Turns (N): 3,700
Current (I): .060 Amps
Core Material: 1110 Low Carbon Steel
Using the equation for Field Strength H = (N*I)/L = (3700*.060)/.017 or H = 13,059 A/m...
Intuitively, that would make sense. However, I know the field calculations change when there there is an air gap vs. no air gap, so I'm not sure what happens when both situations exist simultaneously. What might happen is that the magnetic flux lines may redistribute themselves within the...
Thanks for the reply. Yes, I would think the clamp force would go up since the region that has the air gap (the chamfer area) would be getting closer to the contact plate. However, I'm not sure how the field would change with or without the chamfer, so it may just redistribute and stay almost...
I have a solenoid electromagnet whose cylindrical steel core protrudes out and has a chamfer at the end. When the core end contacts the mating part, the chamfer reduces the actual contact area by 1/2 (compared to the core diameter). I know pull force is dependent on core diameter, but is it...