Microstructure and Hot Deformation Behavior of Fe-20Cr-5Al Alloy

High temperature deformation behavior of cast
Fe-20Cr-5Al alloy has been investigated in this study by performing
tensile and compression tests at temperatures from 1100 to 1200oC.
Rectangular ingots of which the dimensions were 300×300×100 in
millimeter were cast using vacuum induction melting. Phase
equilibrium was calculated using the FactSage®, thermodynamic
software and database. Tensile strength of cast Fe-20Cr-5Al alloy was
4 MPa at 1200oC. With temperature decreased, tensile strength
increased rapidly and reached up to 13 MPa at 1100oC. Elongation
also increased from 18 to 80% with temperature decreased from
1200oC to 1100oC. Microstructure observation revealed that M23C6
carbide was precipitated along the grain boundary and within the
matrix.





References:
[1] J. R. Davis, "Stainless steels,” ASM specialty handbook, ASM
International, Materials Park, Ohio, USA, p. 66, 1994.
[2] Y. Inoue, and M. Kikuchi, "Present and future trends of stainless steel for
automotive exhaust system,” Nippon Steel Tech. Rept. no. 88, 2003.
[3] K. S. Lee, K. H. Oh, W. W. Park, and H. Y. Ra, "Growth of α-alumina
oxide film in high temperature oxidation of Fe-20Cr-5Al alloy thin strip,”
Stainless Steel World 99 Conference, p. 147, 1999.
[4] K. Ishii, M. Kohno, S. Ishikawa and S. Satoh, "Effect of rare-earth
elements on high temperature oxidation resistance of Fe-20Cr-5Al alloy
foils,” Mater. Trans., JIM, vol. 38, p. 787, 1997.
[5] Z. C. Zhou, and F. S. Han, "High-temperature relaxation in a Fe-Cr-Al
alloy,” Phys. Stat. Sol., vol. 199, p. 202, 2003.