Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Long Fiber reinforced materials

Status
Not open for further replies.

hrvat

Mechanical
Nov 29, 2000
14
0
0
US
I curently have an ABS that is not performing well strength wise, and I am considering going to either a long fiber abs or even a long fiber polyester. The original material I used in this aplication was 33%GFN, and the warpage of this curved plastic part was unbearable.

I was told that the long fiber materials will not warp and shrinkage rates are very low.

Any thoughts?

Thanks
 
Replies continue below

Recommended for you

We can offer another alternative yet. We have a new process that may assist. If interested, please let me know.

Thanks,

Joe Miller
 
The addition of fiber will increase the stiffness of your part, however be careful with the orientation of long fibres and the loading of the part.

Shrinkage will also occur in 2 axis but at different %.

It all depends on your product / process and design
 
Long fiber reinforced thermoplastics (LFTP) have more, not less, potential for warpage because the long fibers are much more prone to flow induced orientation.

Shrinkage is primarily a function of process temperatures and fiber volume fraction, there is nothing inherently better about LFTP.

LFTP can have much higher strengths.

How large is your part? How much strength is needed?
 
Is the warpage due to molding or to exposure to elevated temps? You may wnat to look at using an amorphous material rather than crystaline.

We produce polymers that will be able to help.

Regards
 
You'll have to look at the original performance requirements and see why 33% GF nylon product was chosen. Glas reinforced crystalline plastcs do tend to warp if designed improperly. It could be a molding or gating problem is to blame.

Check the overall performance of 33% GF nylon vs long strand ABS (not exactly the most common plastic in use these days). You need to know the end use conditions the part will be exposed to. The ABS should warp less, but with the addition of the long fibers its anyone's guess how much it will warp. It depends an the part geometry, wall thickness, gating and molding.
 
Status
Not open for further replies.
Back
Top