Research On The Detection Methods Of Trace Elements In Alloy Steel

In recent years,the order quantity of nuclear power products of our company has been increasing continuously,and the amount of related elements detected has also been increasing,which puts higher requirements on the detection methods and levels of trace elements.In order to meet its harsh use environment,the range of trace element content in nuclear power products must be strictly and accurately controlled,and there are many shortcoming of existing national standards,which can not meet the needs of detection accuracy,how to efficiently and accurately determine the trace elements,reduce the error value,improve the detection accuracy,and analyze the measurement result is the main research content of this topic.In this work,the application of hydride generators and ICP-MS mass spectrometers was applied to the analysis of trace elements in steel.A method for the determination of P,Sn,Sb,Bi,Pb,As,trace elements in steel by HG-ICP-MS with flow injection technique was established.Through the control variables and comparison with the simple mass spectrometry method,the variables in the experiment were gradually perfected,including the type and concentration of dielectric acid in the solution,the concentration of KBH₄,the flow rate of gas injection and the speed of sample injection,and the optimal test conditions of each element were gradually obtained.In the process of experiment,the method of determination of trace elements in iron and steel was established through the determination of detection limit and sensitivity.The sample was dissolved with hydrochloric acid mixed with nitric acid,and³¹P?¹¹⁸Sn?¹²¹Sb?²⁰⁹Bi?²⁰⁸Pb and⁷⁵As were selected as the isotope to be tested.The experimental results show:the correlation coefficients of the calibration curves of³¹P?¹¹⁸Sn?¹²¹Sb?²⁰⁹Bi?²⁰⁸Pb and⁷⁵As are above 0.999,the recoveries of spiked standards are between 95 and 105,and the relative standard deviation?RSD?of the six-element measurement is less than 5%.The established flow injection HG-ICP-MS method for the determination of trace elements:limit of detection?LOD?is P 0.000144%;Sn 0.0000099%;Sb 0.000033%;Bi 0.0000084%;Pb0.000267%;As 0.0000023%.The RSD?n=11?of the above six elements is less than or close to 8.3%.The results show that the hydride generation method combined with ICP-MS can be used to determine trace elements with high sensitivity,low sample dosage,fast analysis speed,and the separation and identification can be carried out simultaneously.