PMMA screen failure

[CompoMan]

Gents,

I have a PMMA screen of around 800mm x700mm and 6mm thick. If I were to scored the sheet 3mm deep of v shape grove and from one corner of the sheet to another in the form of X. If the sheet is then subjected to impulse pressure of @ 20KPa. Do you think the sheet will break into small pieces or fail at the groves??

 

[patprimmer]

That is low pressure, but still over a tonne of load on the sheet. I would be very surprised if it did not fail in short time. The life will be very dependant on the radius at the bottom of the grove.

Regards
Pat
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[Demon3]

What you describe is very much analagous to a notched impact test. The stresses will concentrate at the crack tip (the sharp bottom of your groove) and the part will very probably fail there.

Chris DeArmitt

"Knowledge has no value except that which can be gained from its application toward some worthwhile end."
Think and Grow Rich - Napoleon Hill

 

[Pud]

I would guess it would fail along the grooves and leave sharp fracture edges.

At low temperature it may fail into many bits as well.

Harry

http://www.tynevalleyplastics.co.uk

 

[CompoMan]

Thank you all for your contributions