Is there an easy way to destroy the internal microphone hardware on iMac? I use a iMac (Retina 5K, 27-inch, Late 2014) and wonder if there is an easy way to destroy the internal microphone hardware. I don't need the microphone.

Assuming I had a guarantee, is it allowed to destroy the microphone?

With DuckDuckGo I found only a software solution: Disable the Internal Microphone on your Mac
No guarantee [nor insurance] is ever going to cover intentional destruction &amp; in fact a fraudulent claim may be an invitation for a nice police visit, dependant on jurisdiction. 

Smacking things with hammers [at your own risk] usually prevents normal operation of delicate electronic devices, though.
Dismantling with a soldering iron might better preserve the surrounding structures.