#TITLE_ALTERNATIVE#

• Main Author: (NIM : 12507021), SAMUEL
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/24187
• Institution: Institut Teknologi Bandung

Alloying elements in the 2024 series of aluminum alloys such as Cu, Mn, and Mg present as solid solution, increase the potential difference between the alloying elements and the matrix (Al) and reduce the corrosion resistanceof the materials. To improve the corrosion resistance, clad coating needs to be applied. However, during heat treatment process, the dissolved elements in <br /> <br /> <br /> <br /> solid solution such as Cu element will diffuse into the aluminum clad while Al elements will diffuse into the aluminum alloys 2024, and this cause thinning of the clad layer and reduce the corrosion resistance of aluminum alloys. Microstructure of 2024 alloys and thickness of clad at various treatments are obtained from metallographic test. EDX analysis was performed to obtain the atomic and mass percent of elements in the alloys and clads. Hardness test was done to determine the effect of Cu on hardness of aluminum alloys 2024 clad after aging. It was found that the average of diffusion coefficient of Cu in Al is 1.77 x 10-14 m2/s, the average of diffusion coefficient of Mg in Al is 2.66 x 10-13m2/s, and the average of diffusion coefficient of Al in Al is 4.34 x 10-14 m2/s. Aging at 190oC for 10 hours is not enough to make the species diffuse into the <br /> <br /> <br /> <br /> clad. The depletion rate of clad was 0,8 &#956;m/hour of heat treatment. The thickness of the clad will no longer meet with the specifications on the heat treatment at <br /> <br /> <br /> <br /> 495oC for 17 hours. The clad will completely finish on the heat treatment at 495oC for 32 hours. In the artificial aging process, it was found that a sharp <br /> <br /> <br /> <br /> increase in the hardness number occured after aging 4 between ± 36,40 HVN on the surface and ± 86,95 HVN at the first point of the transverse position. By addition of 4% mass percent of Cu, it will give increasing in hardness number to 180 HVN. While addition of 0% mass percent Cu will give hardness number of 20 HVN.