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  • 1, stress relief before plating where the maximum tensile strength is greater than 1034Mpa key and important parts before plating should be at 200±10℃ stress relief for more than 1 hours, carburizing or surface quenching parts should be at 140±10℃ stress relief for more than 5 hours.

  • The spring steel wire is made of high carbon and high quality carbon structural steel or carbon tool steel wire rod, and its chemical composition, gas content and non-metallic inclusion must be strictly controlled according to the use of the spring. In order to reduce the appearance of shortcomings and decarbonization layer, the consumption of rod billet to stop surface grinding, if necessary, but also stop peeling.

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