#TITLE_ALTERNATIVE#

• Main Author: R Siagian (NIM : 12103045), Herman
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/6227
• Institution: Institut Teknologi Bandung

Abstract : <br /> <br /> <br /> <br /> <br /> <br /> <br /> One of the high strength low alloy steel (HSLA) development application is material for produce pipe. This HSLA steel that produced by PT. Krakatau Steel will be used in the production of API 5L X-60 Gas Pipe. This Pipe will be used to flow out gases that contains of sour. The diameter of the pipe that will made is affected by strain that force to the steel plate as the material in the production of pipe. In this research the analysis is carried out to study the affect of that strain on the crack propagation toughness of HSLA steel as material of pipe by its KIC. From the test of fracture mechanism, the load (kN) vs displacement (mm) graph obtained will be used to calculate the fracture toughness value that represent by CTOD parameter. This test is determined by using ASTM E1290 standard. The fracture toughness values as the result on this 0%, 5%, 10%, and 15% strain specimens resvectively in a series are 83.8, 67.9, 46.2, and 42.5 Mpa m1/2. Observation on the fracture surfaces is carried out using SEM. The results of the SEM show the type of fracture for 0%, 10%, and 15% strain spesimens resvectively are ductile fracture, ductile and intergranular fracture, and intergranular fracture. To study the effect of strain on strain hardening that occur, in this research the Vickers hardness test is carried out and then converted to ultimate strength of HSLA steel. The results of the strain effect show that the fracture toughness value of steel specimens decrease linearly with increasing in strain, while the hardness and ultimate strength of HSLA steel increasingly with increasing in strain. Besides that, the maximum diameter of pipe that can be made will be smaller with increasing in strain.