Are mobile phone parts interchangeable?

Are parts interchangeable between Android phones? For example... My fiancee has a ZTE Z813 that no longer functions. She upgraded to a ZTE Sonata 3. Needless to say, she's not very friendly to her phones. Do to several drops, her microphone no longer functions properly in calls. I told her to just plug in a headset or Bluetooth device. That worked out well for her. Can I use the mic from hr previous phone to fix her current one? Thank you for you time and expertise.

Regards,

Daniel H.