Abstract：Silver-tungsten alloy is a key material for fabricating microelectronic components and high-temperature resistant components. The accurate determination of silver content in silver-tungsten alloy is of great significance for the quality control of products and the recycling of silver-tungsten alloy waste. The sample was dissolved with sulfuric acid-ammonium sulfate, which could effectively improve the temperature of the digestion system. At the same time, the presence of ammonium ions could complex tungsten ions in solution, thus promoting the digestion of the sample. Under the acid conditions, the sample solution was titrated with sodium chloride standard titration solution until abrupt change of potential, which was named as the end point. Consequently, a method for determination of silver content in silver-tungsten alloy was established by potentiometric titration. It was shown that other coexisting elements in the product (including tungsten, aluminium, cobalt, chromium, copper, iron, manganese, magnesium, nickel and tin) had on interference with the determination of silver. The contents of silver in four silver-tungsten alloy samples were determined according to the proposed method. The relative standard deviations (RSD, n=11) of the determination results were between 0.14% and 0.53%. The recoveries were between 99% and 102%. The proposed method was applied to the determination of silver content in two samples, i.e., AgW20 and AgW80, and the standard method of JB/T 4107.4-2014 was used for verification. It was shown that the two methods had good consistency by both F test and t test.
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