EFFECT OF GELATIN ADDITION ON THE MORPHOLOGY, HARDNESS AND CORROSION RESISTANCE OF Cr-ZrO2 COATINGS

• Main Author: Luthfiani, Febi
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/33938
• Institution: Institut Teknologi Bandung

Automotive and aircraft components require lightweight material with high hardness. Aluminum is a light metal that has a low hardness. Therefore, surface modification is required to increase aluminum hardness without altering its original characteristics. The hardness of the aluminum surface can be increased by the electrodeposition method of mixing Cr, ZrO2, and gelatin solutions. The addition of gelatin to the Cr- ZrO2 layer serves to be a stable suspension. The deposition process is carried out with a temperature variation of 35-60°C to determine the optimal conditions of coating. The electrodeposition process was carried out with the addition of ZrO2 with variations of concentrations of 1, 3, 5, 7, and 10g/L. Then the process of deposition with the addition of gelatin in Cr-ZrO2 coating was done with variation of concentration 1, 3, 5, 7, and 10g/L. The surface morphology was observed by SEM. The effect of gelatin on the deposition process was identified by microvickers method. Corrosion behaviors at different coating content were evaluated by potentiodynamic polarization methods in 3% NaCl solution. Confirmation of Cr bond with gelatin was observed by FTIR. The addition of gelatin on Cr-ZrO2 coating makes the layer darker and the grain is not visible. The hardness of Cr coating was 1097 ± 56VHN. Cr-3g/L ZrO2 coatings of 1294±75VHN. Hardness of Cr and 3g/L ZrO2 with addition of 1 g/L of gelatin of 1220±60VHN. The addition of 1 and 3g/L gelatin can decrease the corrosion rate to 0.15±0.02 and 0.13±0.01mpy compared with Cr-ZrO2 coating.