Effect of CeO2 on Al–Ti–C and matrix conversion between TiC and α-Al orientation relationship

摘要

Abstract AT the present study, Al–5Ti–0.25C–1Ce alloy was prepared by using Al chips, Ti chips, graphite powder and CeO2 powder as raw materials under different process conditions. The effects of reaction temperature and time on the microstructure and refinement effect of Al–5Ti–0.25C–1Ce were systematically investigated. The results show that the best preparation process is holding at 1273 K for 80 min; the best refinement process for commercially pure aluminum is 1.0 wt addition and having for 2 min. EDS analysis of the refined pure aluminum confirmed that the reason for the deterioration of refinement in the Al–Ti–C–Ce system is the massive generation of AlxCy with time, which has a high lattice mismatch with α-Al, leading to the decline of refinement. In addition to this, we demonstrate that TiC crystal plane or direction paralleled to a certain crystal plane or direction of α-Al can be obtained by a specific matrix equation arising from selected area electron diffraction:UVWTiC=01.065901.06590000-1.0659UVWAl,HKLTiC=00.9381700.938170000-0.93817HKLAldocumentclass12pt{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$left {begin{array}{*{20}l} U V W end{array} } right_{{{text{TiC}}}} = left {begin{array}{*{20}c} 0 {1.0659} 0 {1.0659} 0 0 0 0 { - 1.0659} end{array} } rightleft {begin{array}{*{20}c} U V W end{array} } right_{{{text{Al}}}} ,;left {begin{array}{*{20}c} H K L end{array} } right_{{{text{TiC}}}} = left {begin{array}{*{20}c} 0 {0.93817} 0 {0.93817} 0 0 0 0 { - 0.93817} end{array} } rightleft {begin{array}{*{20}l} H K L end{array} } right_{{{text{Al}}}}$$end{document}. Which effectively makes up for the heavy labor of obtaining a single orientation relationship from a single high-resolution transmission electron microscope image and the difficulty in capturing high-definition phase interface information originating from insufficient instrument resolution.