A detection method for determining impurity elements in tungsten carbide

Abstract

The invention provides a method for detecting impurity elements in tungsten carbide, and concretely relates to the method for rapidly detecting tungsten carbide as well as cobalt, nickel, iron, titanium, aluminum, manganese, magnesium, vanadium, chromium, copper, and molybdenum in casting of tungsten carbide by using an inductively coupled plasma-atomic emission spectrometry. A sample is digested in an electrothermal digestion instrument by employing hydrofluoric acid and nitric acid, under condition that a tungsten matrix is not separated, the high purity tungsten matrix is used for preparing a standard work curve, spectrum interference of the tungsten matrix to a to-be-measured element is solved, optimum wavelength of each element is selected, background correction is carried out, and tungsten carbide as well as cobalt, nickel, iron, titanium, aluminum, manganese, magnesium, vanadium, chromium, copper, and molybdenum in casting of tungsten carbide are rapidly detected by using the inductively coupled plasma-atomic emission spectrometry. The detection method has the advantages of simple operation, short detection period, simple sample processing, and wide detection scope, and is suitable for batch production analysis.

Description

technical field [0001] The invention relates to a detection method, in particular to a method for rapidly determining cobalt, nickel, iron, titanium, aluminum, manganese, magnesium, vanadium, chromium, copper and molybdenum in tungsten carbide and cast tungsten carbide by using an inductively coupled plasma emission spectrometer Detection method. Background technique [0002] Tungsten carbide (WC) is the main raw material for the production of cemented carbide. Cast tungsten carbide (YZ) is mainly used for surfacing welding oil drilling tools, building materials machinery, grain machinery and other wear-resistant parts, which can increase its surface wear resistance and strength. The detection methods of cobalt, nickel, iron, titanium, aluminum, manganese, magnesium, vanadium, chromium, copper, molybdenum trace impurity elements are: DC arc emission spectrometry, atomic absorption spectrometry, spectrophotometry or square wave polarography , the defects of these detection ...

AI Technical Summary

Problems solved by technology

[0003] 1. The measurement precision of DC arc emission spectrometry is poor and the detection range is narrow

Impurities greater than a few hundred ppm in cast tungsten carbide cannot be accurately determined

[0004] 2. Atomic absorption spectrometry, spectrophotometry or square wave polarography are single-element determinations. The sample processing is cumbersome and the analysis period is long, so it is not suitable for mass production analysis.

The reports on the determination of impurity elements in tungsten by inductively coupled plasma emission spectrometry mainly include: "ICP-AES determination of impurities in high-purity tungsten" published on pages 71-73 of "Journal of Central South University of Technology", Volume 30, Issue 1, February 1999 element", this determination method can only be used for high-purity tungsten powder, and cannot completely dissolve tungsten carbide and cast tungsten carbide; Determination of high content of vanadium, chromium and cobalt in tungsten carbide. This determination method uses phosphoric acid with high viscosity to dissolve the sample, which is not suitable for equipment with thin capillary tubes. It is easy to make the liquid injection speed uneven, which affects the atomization efficiency and exposure stability. , and can only do more than 0.1% of vanadium, chromium, cobalt, not suitable for the determination of trace elements in tungsten carbide and cast tungsten carbide; "Spectroscopy and Spectral Analysis" Vol.18, No.5, pp576-579, October, "ICP-AES direct determination of impurity elements in tungsten products" published in 1998. This determination method uses ammonia water, which can only dissolve tungsten oxide, but cannot completely dissolve tungsten carbide and cast tungsten carbide; "Metallurgical Analysis", 2013, 33 (9) 77- "Determination of trace metal impurities in high-purity tungsten oxide by co-precipitation separation and enrichment-inductively coupled plasma atomic emission spectrometry" published on page 82, this determination method is only applicable to the determination of tungsten oxide; "Hunan Nonferrous Metals" December 2011 "ICP-AES Method for Rapid Determination of Dozens of Trace Elements in Tungsten" published on pages 60-64 of Volume 27, Issue 6. This determination method requires precipitation to separate the tungsten matrix, and tungstic acid precipitation is easy to adsorb iron, titanium, vanadium, and molybdenum. element, the detection result is low, which affects the measurement accuracy; the Chinese patent publication number CN 103529015 A discloses "Analysis and detection method for cobalt, nickel, iron, titanium and chromium in tungsten carbide", the detection method uses sulfuric acid- The amount of ammonium sulfate cannot completely dissolve pellets or single crystal cast tungsten carbide; the sample is dissolved using the above four reagents in an amount of 25mL, and the treatment process is longer; when detecting trace amounts of cobalt, nickel, iron, titanium and chromium, due to the tungsten matrix in the standard solution The amount of tungsten in the sample does not completely match the amount of tungsten matrix, baseline stratification will occur, and the content of cobalt, nickel, iron, titanium and chromium trace elements cannot be accurately detected, which will affect the accuracy of the measurement

[0006] In summary, there is currently no method for the rapid and simultaneous determination of cobalt, nickel, iron, titanium, aluminum, manganese, Determination methods for magnesium, vanadium, chromium, copper, molybdenum

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