bonding ryton to 316

[boldfish]

What are some typical types of metal preparation that must occur to ensure sufficient bonding of ryton to 316 stainless steel during molding?

We have tried blasting the 316 to roughen the surface but the ryton does not adhere adequately.

Any suggestions?

 

[Pud]

It's difficult to get any plastic to bond directly to metals. Usually there is a mechanical 'key' feature (such as holes, grooves, knurls, etc) to give the required retention.

(Also don't forget the metal inserts need to be at 135 deg C min before overmoulding them in PPS)

Rgds


H

 

[patprimmer]

I agree with Pud

It will be difficult to get Poly Phenylene Sulfide to bond to any metal, and I would add that it will be more difficult to get it to bond to stainless steel.

Some sort of primer, like a polyurethane just might help, but I doubt it. Also, toxic gasses might be emitted from the primer during moulding at the temps required by PPS.

Even if you got some initial bonding, the difference in co-efficient of thermal expansion would severely strain the interface during even moderate thermal cycling.

A good mechanical key that will withstand some stress due to differential expansion as well as the normal load will be required.

I do not think that a surface treatment will provide sufficient key. It will undercuts or holes clean through the metal to hold.



Regards
pat pprimmer@acay.com.au
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