Effect of cerium and thermomechanical processing on microstructure and mechanical properties of Fe-10·5Al-0·8C alloy

摘要

The effect of cerium content and thermomechanical processing on structure and properties of Fe-10·5 wt.%Al-0·8 wt%C alloy has been investigated. Alloys were prepared by a combination of air induction melting with flux cover (AIMFC) and electroslag remelting (ESR). The ESR ingots were hot-forged and hot-rolled at 1373 K as well as warm-rolled at 923 K and heat-treated. Hot-rolled, warm-rolled and heat treated alloys were examined using optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction to understand the microstructure of these alloys. The ternary, Fe-10·5 wt.%Al-0·8 wt.%C alloy showed the presence of two phases; Fe-Al with bcc structure, and large volume fraction of Fe₃AlC_0·5 precipitates. Addition of cerium to Fe-10·5 wt.%Al-0·8 wt.%C alloy resulted in three phases, the additional phase being small volume fraction of fine cerium oxy-carbide precipitates. Improvement in tensile elongation from 3–6·4% was achieved by increasing the cerium content from 0·01–0·2 wt.% and further improvement in tensile elongation from 6·4–10% was achieved by warm-rolling and heat treatment.