Determination of 19 Elements in Titanium and Titanium Alloy by Inductively Coupled Plasma Atomic Emission Spectrometry with Microwave Digestion

The effects of digestion method, digestion acid system, heating up time, and target temperature on sample digestion efficiency were investigated in this experiment. A method was proposed for simultaneous determination of 19 elements, including Fe,Si, Mn, Mo, B, Al, Sn, Cr, V, Zr, Mg, Nb, Pd, Ni, Ta, W, Nd, Ru, and Cu in titanium and titanium alloy by inductively coupled plasma atomic emission spectrometry(ICP-AES) with microwave digestion. 0.100 0 g of the titanium or titanium alloy sample was placed into a polytetrafluoroethylene digestion tank, and then 8.0 mL of 33%(volume fraction) hydrochloric acid solution, 3.0 mL of 25%(volume fraction) hydrofluoric acid solution, 1.0 mL of 50%(volume fraction) nitric acid solution, and 0.5 mL of perchloric acid were added. The mixture was placed into a microwave digestion instrument, keeping for 10 min at the highest digestion temperature of 120 ℃. After cooling to room temperature, the digestion solution was made its volume up to 50 mL with water, and the elements with mass fraction not exceeding 1.0% were detemined by ICP-AES. The sample solution was diluted 10 times and the elements with mass fraction greater than 1.0% were detemined by the same method. As shown by the results, linear relationships between the corresponding response intensity and mass concentration of 19 elements were found in definite ranges, with detection limits(3s) of 0.006-0.033 mg·L⁻¹. Four titanium alloy standard samples and three actual titanium alloy samples were analyzed, and the obtained results were compared with those of the standard method GB/T 4698 series. It was shown that the determined values of this method were basically consistent with the certified values.Test for precision was made on two standard samples and two actual samples of titanium alloys. Each sample was determined five times in parallel, with RSDs of the determined values less than 4.0%.