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The the phenol sulfonate high-speed tin plating solution (PSA) is an environmentally friendly, high efficiency, excellent performance tin-plating bath. With continuous electrodeposition, the the solution Sn 2 in the electroplating process, the conversion to the Sn 4 , thus affecting the bath performance and the quality of the coating. Paper iodometric method Determination of Sn by 2 and the Sn 4 concentration. Observed by optical, scanning electron microscopy pictures, electrochemical experiments, the porosity experiment, neutral salt spray test different Sn 4 concentration plating coating surface morphology and corrosion resistance law. The results show that Sn 2 , the Sn 4 content of at least 28g / L, the corrosion resistance of the tin plating layer strongest. PSA tin plating bath the tin ion transformation of under five different conditions (still placed stirring placed, plating temperature, blowing air, oxygen blowing) static (non-plated), and a tin mud. The results showed that the tin ions is also produced in the plating solution under the conditions of oxygen gas blowing, tin mud up to the fastest conversion. Then the sequence is a plating temperature, air was blown into the stirred placed stationary when placing the plating solution. This experiment indicates that the tin ions in the plating solution into the amount of oxygen, the temperature of the plating solution. Dynamic (plating), designed two experimental program, a continuous plating Sn 2 28 g / L, Wuxi mud bath to study ion transformation of tin mud generated tin plating and tin ions under the conditions of the appearance of the morphology and corrosion resistance variation. The results show that, in the Sn 2 higher concentration the Sn 4 concentration minimum Wuxi clay, the coating surface is smooth, crystallization is also more detailed. With the Sn 4 concentration of rise, the increase in coating porosity, reduced corrosion resistance. Another experimental program to simulate real-tinned, maintaining the Sn 2 concentration (when the the Sn 2 concentration of high concentration of 20g / L supplementary the tinning liquid), electroplating, The results showed that the appearance of the coating morphology and Sn 2 , Sn 4 , tin mud bath still has a great influence on the coating. End of this article also affect the coating properties of tin mud experimental XRD performance testing, analysis of the composition of the tin mud. The results showed that the tin mud containing C, O, S, Sn, and other elements, the main component for the SnO 2 .
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