The Cu site in L1(0)-ordered ternary FePtCu alloy was quantitatively determined using atom location by channeling enhanced microanalysis (ALCHEMI). The lattice parameter measured by XRD result was a = 0.388 +/- 0.0003 nm and c = 0.369 +/- 0.0009 nm with an axial ratio c/a of 0.951 +/- 0.0003 for ternary L1(0)-ordered FePtCu phase. The alloy composition of bulk ternary L1(0)-ordered FePtCu phase was Fe40Pt50.4Cu9.6 measured by inductively coupled plasma atomic emission spectrometer (ICP-AES). The ALCHEMI result obtained from calculation of the characteristic X-ray spectra demonstrates Cu almost occupies the Fe site in ternary L1(0)-ordered FePtCu alloy.

Keywords: L1(0)-structure; Cu site; FePtCu alloy; ALCHEMI