BeCu ribbon Alternate

[Nellysdad]

We use a BeCu ribbon in one of our loudspeakers. It is under constant vibration/movement and we therefore need the constant flexibility (elasticity?) property of this material. Does anyone know of an alternate material that will withstand constant movement and heat up to 80 deg c without deteriorating? I have been told that Tellurium copper may be suitable. Any ideas on this matter is welcome.
Regards

 

[NickE]

You might also want to try Brush Wellman Alloy 360. Its a BeNi alloy that has really high strength (~270ksi tensile strength, little stress relaxation up to 400F, and a fatigue limit ~90ksi.

Its conductivity is ~4% IACS. About 7times greater than 17-7 steel. (I dont work w/ BeCu so I dont have values handy.)

Nick

(I'm an Live audio engineer in my spare time, what driver is this and do you need prototypes tested?) (that last bit was a sort of joke)

 

[Nellysdad]

Thanks Nick but I am trying to move away from Be..I forgot to mention that in my original posting.
Regards

 

[Goahead]

Beryllium copper is an excellent material formed in soft condition and precipitation hardened by a low temperature (600F = 316C) thermal treatment. It is available in solution annealed, quarter hard, half hard and hard condition. No reason was given for the need to find a substitute material.
Tellurium Copper is a free machining alloy for fasteners, not for above usage.

http://www.welding-advisers.com/

 

[Nellysdad]

Sorry for not specifying my need for an alternate.
The writing is on the wall. Eventually, it will be banned in Europe.
Regards

 

[unclesyd]

Have you look at Elgiloy?

http://www.elgiloy.com

 

[sreid]

Tantalum foil might work. The resistance is in the same range as Be-Cu. Tantalum is a heavy metal but has almost perfect bio-compatibility.

 

[EdStainless]

So which properties do you need?

Conductivity/resistivity
Thermal expansion
Thermal conductivity
Strength
Modulus (stiffness)
Fatigue strength

Put these in order and then we can hunt for an alternate.
Be is quite harmless, unless you inhale dust.

I agree Nick, BeNi is an amazing material. It is almost impossible to thermal fatigue it.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[unclesyd]

Do we need to add magnetic properties?

 

[rorschach]

Brush Wellman has a relatively new material called Toughmet that is a nickel tin copper spinoidal alloy that might be worth looking at. It may not be typically available in ribbon form. If you're buying enough of it Brush may do it for you however.

Inconel X-750, Elgilloy and MP35N are excellent spring materials that are virtually fatigue proof especially the latter two, but they are not terribly conductive. they are also non-magnetic. Is conductivity a concern?

 

[drawoh]

Nellysdad,

Titanium has similar elastic modulus and stress characteristics to beryllium copper, although the mass is very different. Is that what you are after? Beryllium copper is only about 2% beryllium.

I did a quick web search on beryllium and banning, and I did not see anything absolutely explicit about BeCu. How likely do people thing this is?

JHG

 

[Rossmetals]

Which alloy is currently used? There are several BeCu alloys.

Depending on the Yield Strength requirements, there are several bronze and Cu/Ni/Si alloys that are being utilized.

Most copper alloys used in spring and connector applications can withstand Stress relaxation under 100 degC.

check out

http://www.avins.com