Answer: Microstructure are material structures seen at the micro level. And Mascrostruture is The gross structure of a material or tissue as visible to the unaided eye or at very low levels of magnification.
Explanation: As nouns the difference between macrostructure and microstructure is that macrostructure is the gross structure of a material or tissue as visible to the unaided eye or at very low levels of magnification while microstructure is the fine structure of a material or tissue as revealed by microscopy.