On the electroplating of laminated chromium
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A microprocessor-controlled flow plating process was developed to deposit laminated chromium consisting of alternating layers of low contraction (LC) and high contraction (HC) chromium. The automated plating system contains a large number of variable parameters designed to allow the use of multiple plating modes. The available modes include a combination of direct current, interrupted, periodic reverse, pulse and laminated chromium plating.
The laminated plating experiments were conducted at LC/HC solution temperatures of 85 and 55°C, current densities of 120 and 45 A dm−2, and at LC/HC duty cycles to produce spacings between 0.01 and 2.7 μm. Under these plating conditions, deposits with hardness values between 655 and 1089 KHN (Knoop hardness number, kg mm−2) and tensile strengths between 6.8 and 57.2 were obtained.
KeywordsPhysical Chemistry Chromium Tensile Strength Variable Parameter Duty Cycle
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