Determination of Mo, Al, W, Ti, Nb, Fe, Si, Mn in K4648 Nickel-based Superalloy by Inductively Coupled Plasma Atomic Emission Spectrometry

A method was established for the determination of Mo, Al, W, Ti, Nb, Fe, Si, and Mn in K4648 nickel- based superalloy using inductively coupled plasma atomic emission spectrometry(ICP-AES). The alloy samples were digested with aqua regia(3:1 volume mixture of concentrated HCl and HNO₃) supplemented by incremental HCl additions during digestion. The nebulizer gas flow rate was optimized at 0.70 L/min. Interference effects from the nickel matrix and coexisting elements were investigated systematically, and the optimal analytical lines were selected: Mo202.095 nm, Al167.078 nm, W207.911 nm, Ti334.941 nm, Nb309.418 nm, Fe238.204 nm, Si251.612 nm, and Mn257.611 nm. Calibration curves were constructed using matrix-matched standard solutions. Linear correlation coefficients are above 0.998 for all elements, and method detection limit shall not be higher than≤0.0008 μg/mL. For actual sample analysis, relative standard deviations(RSD, n=10) range from 0.20% to 1.00% and spike recoveries range from 97.4% to 101.0%. Comparison tests on candidate reference materials of K4648 show that the measured values are in good agreement with the certified values.