INVESTIGATION STUDY OF ANTIBACTERIAL PROPERTIES OF CU-ZN SUPERHIDROFOBIC COATING LAYER PRODUCED BY PULSE ELECTROPLATING ON API 5L GRADE X52M STEEL WITH BACILLUS ARYABHATTAI BACTERIA IN SEAWATER ENVIRONMENT

• Main Author: Yudhanto, Harigo
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/85201
• Institution: Institut Teknologi Bandung

Steel is the most widely used alloy metal in the world and has many advantages. However, steel is prone to corrosion due to the high water absorption of the steel surface. Corrosion is something that cannot be avoided, but it can be controlled. Corrosion influenced by microorganisms is one of the main problems in the oil and gas exploration industry. Microorganisms, including bacteria, fungi, archaea, and microalgae, can affect corrosion both directly and indirectly. Sulfate-reducing bacteria (SRB) are the primary contributors to MIC. One type of SRB is Bacillus aryabhattai. Superhydrophobic coatings have a static contact angle greater than 150° and a dynamic contact angle less than 10°. A rough surface morphology and low surface energy are key to maximizing superhydrophobicity. Fabrication of superhydrophobic coatings using pulse electroplating has the advantage of producing smooth, minimally porous deposits with good current efficiency. This study investigates how deposition time affects the contact angle and antibacterial properties of the coating at optimal parameters. Before the fabrication of the superhydrophobic coating with a Cu-Zn deposit, the sample was first prepared. The fabrication process was carried out with deposition times of 20, 30, 40, and 50 minutes. The process continued with immersion in a solution for 30 minutes to achieve hierarchical micro-nano structures. The sample was then immersed in myristic acid solution for 36 hours to reduce surface tension. The sample was then measured for its contact angle, with the highest contact angle being considered the optimal parameter. The sample with the optimal parameter was subjected to various tests, including surface roughness, abrasion resistance, self-cleaning properties, sessile and planktonic bacteria tests, electrochemical tests, and Scanning Electron Microscope-Energy Dispersive Spectrometry (SEM-EDS) characterization after 28 days of immersion. The results showed that the highest contact angle of 160.50° was achieved when the deposition time was 40 minutes. At this condition, the coating had good homogeneity due to low standard deviation and was resistant to abrasion up to 40 cm, with good self-cleaning properties. The superhydrophobic coating also exhibited good antibacterial properties with a sessile bacteria percentage of 29.30% after 21 days of immersion. SEM-EDS characterization indicated that the superhydrophobic coating had fewer sessile bacteria adhering to it.