A STUDY OF EFFECT OF CYCLIC FREQUENCY AND CO2 IN DISSOLVED NaCl TO THE FATIGUE RESISTANCE OF LOW CARBON STEEL AT ROOM TEMPERATURE AND OPEN SYSTEM

• Main Author: Wisnu Wardhana - Nim: 13714027 , Tezar
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/31273
• Institution: Institut Teknologi Bandung

<p align="justify">Based on research, fatigue corrosion testing at lower cyclic frequencies can have a significant effect on decreasing fatigue life of material. Coupled with the increasingly acidic conditions of sea water caused by CO2 gas that dissolves into sea water to form carbonic acid. This study simulates corrosion attacks from seawater in mid-sea structures with low and high cycle frequencies. The material used is low carbon steel with a content of 0.173% C. 3.5% NaCl solution is used as artificial sea water coupled with dissolved CO2 gas. Fatigue and corrosion testing tired of producing four SN curves, namely in an atmospheric environment, in a low cycle (5 Hz) and high (30 Hz) NaCl environment, and in a low NaCl + CO2 environment (5 Hz). The fatigue life of the specimen in a corrosive environment with a low cycle will be lower than the high cycle. Fractographic observations showed that there was a ratchet mark and found pitting on a fatigue corrosion specimen that was significant at low stress. The influence of the surface of the specimen is very influential on the fatigue life of the material which can produce stress concentration on its surface. <p align="justify">