Determining 4 elements in nickel-based alloys by microwave digestion ICP-AES method
LIU Fang1, ZHAO Wei-xing2, DONG Pan2, HOU Xiang-dong3, HUO Yu-hui4
1. Department of Modern Chemical Engineering, Shanxi Engineering Vocational College, Taiyuan 030009, Shanxi, China; 2. Technology Center, Shanxi Taigang Stainless Steel Co., Ltd., Taiyuan 030003, Shanxi, China; 3. Department of Metallurgical Engineering, Shanxi Engineering Vocational College, Taiyuan 030009, Shanxi, China; 4. Surrey International Institution, Dongbei University of Finance and Economics, Dalian 116025, Liaoning, China
Abstract：Nickel-based alloys are an alloy with both good corrosion resistance and considerable strength at high temperatures. In its composition analysis, there are difficulties such as difficult to dissolve samples and inaccurate analytical determination. The different was studied between the samples treated by traditional wet digestion and modern microwave digestion methods under different mixed acid types and ratios. It is found that the insoluble Ni-based alloy samples can be decomposed to clarified state by HCl-HNO3 (10∶1)(volume ratio, the same below), which can replace the decomposition method using strong corrosive HF as co-solvent. In addition, effect of making working curves with Ni (60%) and Cr (22%) (mass fraction, the same below) as substrates on the determination of Co, Fe, Mn, Ti and other elements was investigated. The results show that using small amount of HCl-HNO3(10∶1) mixed acid as solvent and microwave digestion method to treat samples results in low acid consumption, short digestion time and accurate determination results. Working curves are produced using multi-element mixed standard series solutions and the results is obtained by subtracting the Ni-Cr matrix blank, then it is compared with the certified values of Inconel standard BS 625E (UNS Number N06625). The relative errors are in the range of -10.612 9% to 8.709 7% and relative standard deviations of 0.062 9% to 5.686 4%. The results shows that this method can accurately determine the mass fraction of Co, Fe, Mn, Ti and other elements in the insoluble nickel-based alloys in the range of 0.001% to 5%. The results can provide a feasible method for the digestion of insoluble Ni-based alloy and the determination of Co, Fe, Mn, Ti and other elements in the alloy.
2023, Vol. 33 
