Pengaruh Penambahan Aluminium Terhadap Daya Adhesi Dan Ketahanan Korosi Cat Epoksi

Dalam dunia industri, perlindungan terhadap korosi dengan cara memperlambat laju korosi pada material merupakan suatu hal yang penting. Salah satu metode yang sering digunakan ialah pelapisan. Sistem kerjanya ialah mencegah terjadinya kontak antara logam yang dilindungi dengan lingkungannya. Material substrat yang digunakan ialah baja SA 516 grade 70 yang sering digunakan dalam industri sebagai material untuk bejana tekan. Pada penelitian ini, baja dilapisi dengan cat Epoksi dengan variabel penambahan Aluminium sebesar 5%, 10% dan 15%.. Hasil pengujian menunjukkan perubahan pada propertis cat epoksi. Pengujian Pull-Off menunjukkan bahwa semakin bertambah kadar aluminium maka akan menurunkan Daya Adhesi cat. Ketahanan korosi meningkat seiring bertambahnya kadar aluminium yang diuji dengan metode scratch untuk salt spray test dan metode unscratch untuk pengujian immers. Pengujian Morfologi menggunakan SEM menunjukkan persebaran aluminium yang dianalisa menggunakan EDX. Daya Adhesi tertinggi dimiliki spesimen 0% dengan nilai 10,26 Mpa. Ketahanan korosi paling tinggi dimiliki spesimen dengan 15% yaitu rating 9 untuk salt spray test dan blister size no 10 untuk pengujian immers. ========== Corrosion control by reducing corrosion rate on material is an important thing in industrial applications. Coating is the common used method in this purpose. The working system of the method is by anticipating contact between the coated metal and its environment. In this research, substrate material was steel SA 516 grade 70. The material is mostly used in industry as pressure vessel material. The substrate was coated by Epoxy-paint with a variation of Aluminum addition 5%, 10%, and 15%. Several tests were carried out and its results showed some change of epoxy coating properties. Pull-Off test showed that addition of aluminum paste reduces coating adhesion strength. Corrosion resistant of epoxy coating were lowered as the aluminum paste content increases due to result of scratch method for salt spray test and unscratch method for immersion test. SEM was used to investigate morphology of coating surface and texture was changes at the interface of coating and EDX to analyze dispersion of aluminium. The highest adhesion strength was resulted by specimen with 0% aluminum with value 10,26 Mpa. Specimen with 15% aluminium has the highest corrosion resistance with rating 9 for salt spray test and blister size no 10 for immersion test