STEORN DEMO LIVE & STREAM in Dublin, December 15th, 10 AM

[maw2432]

Why is there 100% resistance to the Finemet cores when there is plenty of research pointing to the Finemet as possibly being the core material in the Orbo.  The Metglas cores are accepted without question or any research pointing to it, except for it having the highest permeability.

Finemet is much softer than metglas, and page 8 of the Finemet brochure suggests this due to it's nano-crystalline structure.  I believe Steorn said they're using a very soft magnetic material.  He didn't say anything about having the highest permeable material.

On page 2 of the Finemet brochure, it says:

1) Satisfy both high saturation magnetic flux density and high permeability.  High saturation magnetic flux density comparable to Fe-based amorphous metal. High permeability comparable to Co-based amorphous metal.

You see, there is a difference between the amorphous metals, such as Metglas, and the nano-crystalline materials such as Finemet.  The brochure is comparing the Finemet with the amorphous metals.  Finemet has high saturation, high permeability comparable to metglas, and is a much softer material than metglas.

I'm going to sit on the sidelines for a while and let you guys figure this stuff out.  I'm tired of defending everything I say here.  I believe finemet is more promising than the metglas.  They both need to be tested and results compared.  It's that simple.


GB

GB,  Do you have any suggested part numbers and where to order Finemet cores?

I have some test equipment ordered and will test both when it arrives.   

Thanks

Bill

[PaulLowrance]

I also applaud those who do not join in the egostorms that arise from time to time.

I applaud those who can post information and what they believe is truth without concern that others might falsely believe they are being egotistical.

[mondrasek]

I received my cores yesterday.  Interesting the results.  They do NOT pull in as strong as ferrite...

Hey Ben, could you clarify for me what you meant by, "They do NOT pull in as strong as ferrite"?

Thanks,

M.

[gravityblock]

GB,  Do you have any suggested part numbers and where to order Finemet cores?

I have some test equipment ordered and will test both when it arrives.   

Thanks

Bill

That is a good question.

I haven't been able to find the ordering specifications for the Finemet "FT-3L" cores, it may be a special order.  I would suggest contacting Finemet.  Phone numbers are in the finemet brochure I posted earlier.  I can find the "H" and "M" types, but not the "L" types. 

We're interested in the FT-3L Finemet cores.  We want the "L" type because the magnetic field is applied vertically to the core plane during annealing.  The "L type" won't need a small reset current after the pulse, which is required in the Metglas MAGAMP Square Loop Cores and the finemet "H" type cores for them to become fully attractive again.  <----- That statement is another 10 pages of posts disputing this fact.

I won't be around to defend this statement.  All one has to do is compare the B-H curves of the Finemet "L type" to the M and H types along with the Metglas MAGAMP Square Loop Cores.  The finemet "H" type is a square loop core and will need a small reset current just like the Metglas square loop cores.  This is a good reason why the square loop cores are not the right choice for the Orbo.


Take care and good luck,

GB

[gravityblock]

Hey Ben, could you clarify for me what you meant by, "They do NOT pull in as strong as ferrite"?

Thanks,

M.

Because they are square loop cores and they will need a small reset current in order for the cores to become fully attractive again.  Square loop cores are not a good choice in my opinion.  I'm just going to say it, square loop cores are a terrible choice for the Orbo, IMO.

GB