#TITLE_ALTERNATIVE#

• Main Author: (NIM : 23710010); Pembimbing : Dr. Ir. Aditianto Ramelan, ANDI
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/14872
• Institution: Institut Teknologi Bandung

Hard chromium plating is being produced to have corrosion, wear and heat resistance surface, certain electrical conductivity, or to restore dimension of undersized parts. In this research, it will be discussed effects of using catalyst H2SO4 or Na2SO4 to efficiency, hardness and surface morphology of hard chromium plating. The solution is cromic acid (CrO3) 300 g/L with current density 50 A/dm2, temperature 550C and stirer’s speed 100 rpm. The results of hard chromium plating are being analyzed its current efficiency, appearance and being characterized by hardness, thickness test and observation to the surface <br /> <br /> <br /> <br /> <br /> morphology. From the analysis, it can be concluded that optimum efficiency of hard chromium plating is achieved with using catalyst Na2SO4, that is 12,9% with 1 w/w % SO4 <br /> <br /> <br /> <br /> <br /> 2- to CrO3. Hardness of chromium plating which is being produced by using catalyst Na2SO4 doesn’t have any significant difference (846 – 989 VHN) if it’s compared <br /> <br /> <br /> <br /> <br /> to plating which is being produced by using catalyst H2SO4. Weight per weight percent of SO4 2- to CrO3 that yields optimum plating hardness for both catalyst is 1 w/w %. Optimum thickness of hard chromium plating is being reached with using catalyst Na2SO4, that is 20,7 &#956;m with 1 w/w % SO4 2- to CrO3. Surface morphology of hard chromium plating which is produced both catalyst Na2SO4 or H2SO4, has cracks and many domelike aggregate, except for plating which is produced by using catalyst Na2SO4 with 1 w/w % SO4 2- to CrO3, it has few domelike aggregate, and plating which is produced by using catalyst H2SO4 with 0,67 w/w % SO4 2- to <br /> <br /> <br /> <br /> <br /> CrO3, it is crack-free and milky type. It is needed to do more experiments to understand effect of catalyst in hard chromium plating in details.