Effect of zirconium content on the microstructure of ODS FeCrAl alloys

Summary The influence of zirconium content on the microstructure of aluminum‐containing ODS ferritic alloy was studied. Four kinds of 13Cr4Al ODS alloys with different Zr content between 0 and 1.2 wt% were prepared by high energy ball milling and hot isostatic press. The zirconium content and occurrence state were determined by composition and phase analysis as well as microscopic characterization. The results show that the addition of Zr in ODS FeCrAl alloy can change the type of the dispersed particles significantly from Y‐Al‐O particle to Y‐Zr‐O particle, and the number density and distribution of the dispersed particles are closely related to the Zr content. The particle number density increases along with the increase of the Zr content, while the average particle size decreases obviously when the Zr content increase from 0 to 0.6 wt%. But when the Zr content rises to 1.2 wt%, it cannot dissolve into the matrix completely during the ball milling, and a coarsen Zr rich phase can be found in the milled powders. It is considered that the addition of 0.6 wt% Zr can best elaborate the microstructure of the ODS FeCrAl alloy.