Reducing Pulling Effect of Magnetic Field?

Why are you certain that the induced magnetic field is causing your silver buttons to move or rotate? 120 kHz is well above the frequencies of any mechanical resonances for all but very small smallest particles. Are there other sources of vibration in your equipment which may be causing the problem?

And would you describe, please, the physical relationship between the silver buttons and the melt? Are these buttons floating on the melted filler metal? How is the workpiece oriented, etc., etc?

Are there other sources of vibration in your equipment which may be causing the problem?

Well, there is no such problem.

And would you describe, please, the physical relationship between the silver buttons and the melt? Are these buttons floating on the melted filler metal?

The copper surface is first cleaned (by acid cleaning, wire brushing) then flux paste is applied above that filler metal strip (which also contains silver) is placed then again flux & then Silver button (size 2.5 x 8 x 10). While brazing first flux melts then filler metal & fills the joint between the workpiece (copper) & Silver button by capillary action, which makes the button float

How is the workpiece oriented, etc., etc?

Are you quite sure that you are not mixing up ultra sonics with high electrical frequencies? I would not expect vibration, especially at this frequency, to be a problem. It might be induced currents in the button, being attracted in some way.....

Induction (high frequency electricity) is used (in my kitchen as well for example) to heat up ONLY things made of iron/steel, so you only heat the pot, not the hot plate (wrong name really, maybe "cold plate" would be better!!) itself!!

It saves money as it is very energy efficient and is faster than most other methods of hot plate cooking....it also disperses less heat into the atmosphere of the kitchen...and is even MORE controllable than gas!!! You can place a piece of paper between a frying pan and the hotplate, to catch fat and the paper does not even turn brown.....the hot plate just gets a little bit warm from the conducted heat from the pot only.....

I seem to have diverted from the real reason of this blog......sorry.

I would suspect that the buttons are being "dragged" electrically out of alignment, how sad. I hope the higher frequencies help you.....

By the way, do the buttons ALWAYS align themselves (wrongly) in the same way? If yes, maybe you need to redesign the button so that it aligns itself correctly under this induction, a change in shape might help.....