Question

why crystal is a widely used material?why amorphous material is so brittle​

Answer 1

Explanation:

Below their glass transition temperature, amorphous polymers are usually hard and brittle because of the low mobility of their molecules. ... Crystalline regions of the polymer are linked by the amorphous regions. Tie molecules prevent the amorphous and crystalline phases from separating under an applied load

Answer 2

$\huge\mathfrak\green{ANSWER}$

Single crystal silicon is the most widely used semiconductor material as a substrate material due to its excellent machinability, mechanical stability, and the potential to combine sensing elements and electronics on the same substrate.

The internal pressure helps deformation, and under some precise physical circumstances the material becomes mechanically unstable. The effect is very sensitive to the material constants and can explain extreme brittleness or large ductility. The approach can be extended to amorphous materials.

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