Has anyone heard of "Impact" welding plastic?

[kennedyg]

Several months ago I read an article about a new technique for joining plastic parts. It involved sliding a boss into a hole at a high rate of speed. The design was to have an interference fit. A small displacement at high velocity is intended to generate sufficient heat to weld the parts together.

I cannot recall any particulars about the story or the source and was wondering if anyone had heard of anything like this.

 

[eholmes]

I've also heard this referred to as friction welding, if I'm thinking of the same article. Eholmes

 

[PrentP]

You might be thinking of linear friction welding (also known as vibration welding). See

http://www.metalwebnews.com/howto/plastics/welding-plastics.pdf

. Or visit The Welding Institute at

http://www.twi.co.uk/j32k/protected/band_3/pjkfwplast.html

Regards,

Peter P

 

[dukane]

Sir- I too remember seeing this article a few years ago. At that time I believe Lucent Technologies/AT&T/Bell Labs or some subgroup of theirs was doing this. You're right in that all it relied upon was a "smashing" of one part with studs into another mating part with holes sized to accept the studs and provide some shear between the studs and holes. I believe the part was a telephone handset. I've looked through a couple of files for this article but am unable to locate it. They said it was the greatest thing since sliced bread but I've not seen it mentioned since. The obvious drawback is the induced and unrelieved stress that will be carried in the boss' hole walls. Ultrasonic shear welding is a far more conventional process with better known design parameters and you would not have to pay a royalty (which I think these guys wanted). If you are interested in pursuing this, please check out an ultrasonic company's web site and submit a request to their applications dept. for further info.

 

[dukane]

As an addendum to my response yesterday- See US Patent #
4,997,500. Hope this helps. ( I would still go with ultrasonics though!)