3.3. Effect of Ti content on mechanical properties
3.3.1. Mechanical properties of as-cast specimens
The microhardness values of the ferritic matrix with increasing
Ti content in the as-cast specimens were 168.8, 177.3 and 182.9,
respectively, which showed a rising trend mostly due to the precipitation of thefine Laves phase Fe2Nb and the Ti solid-solution
into the ferritic matrix. Fig. 9 presents the variations of tensile
strength and elongation with Ti content in the as-cast specimens at
room temperature. It can be seen that the tensile strength decreases
from 385 to 363 MPa as the Ti content increases to 0.46 wt% and the
elongations with increasing Ti content are 10.2%, 4.5% and 2.7%,
respectively. The elongation of the three steels declines sharply. This
means the variation tendency of the elongation with increasing Ti
content is in accordance with that of the tensile strength