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As the grain size decreases, the ductile to brittle transition temperature _________

As the grain size decreases, the ductile to brittle transition temperature _________ Correct Answer decreases

As the temperature decreases, the lattice friction for dislocation movement increases which causes a brittle fracture in the material. If the grain size is smaller, it can withstand the lattice friction at temperature. Also, it will resist the brittle fracture.

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