Measuring the effect of temperatures on the ductile brittle transition

Abstract

In this study is spotlighted on the ductile-brittle transition behavior of carbon steels when the
effect over wide range of different temperture and strain rates it. and knowlege the mechanical
properties of the steel.By breaking a notched bars, the ductile brittle transition temperature
(DBTT) is measured, it was prepared these samples by the ratio the radius of the notched and the
minimum diameter size. the ratios of carbon steels was (0.1, 0.4 and 0.8). Tests are done by a
pendulum-type impact tester for measuring the energy absorbed in the fracture over wide a range
of temperture. Also it presented an discussed the effect of the temperature rise and low on
ductile-brittle transition curve. From here, it leads to the conclusion that with the temperture low
to less than zero degree, it is the yield strength of a ferritic steel increases rapidly. And in a fairly
narrow range of temperture which locates TB, where the fracture mode becomes brittle and the
toughness descreases. This leads that to the ductile brittle transition temperature is important,
because the steel is a much greater tendency to shatter when it is cooled less than DBTT instead
of deforming or bending.