#TITLE_ALTERNATIVE#

• Main Author: SIHOTANG (NIM 12103057), RUDYANTO
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/9163
• Institution: Institut Teknologi Bandung

The need of industry for using stainless steel has been increasing recently. One of the families of stainless steels that is interesting for research and development is duplex stainless steel. Duplex is a grade of stainless steel that has dual phase, ferrite and austenite.<p> <br /> <br /> <br /> <br /> <br /> <br /> <br /> Accurate metallurgical science is needed to design duplex stainless steel. In order to obtain this, the Schaeffler constitution diagram is used as the design diagram for making this grade. The information concerning the influence of alloyed elements on volume fraction change of ferrite and austenite is useful for the design of stainless steel production on an industry-wide scale. Isothermal and anisothermal heat treatments are also done at temperatures of 400oC, 600oC, 800oC with holding times of 1, 3, and 6 hours to study the level of as cast alloy microstructure change and to identify the sigma phase (detrimental phase) that appears in the alloy.<p> <br /> <br /> <br /> <br /> <br /> <br /> <br /> From the analysis results of obtained data, conclusions can be made that alloy 2 (28.74% ferrite), alloy 3 (58.52% ferrite), and alloy 4 (80.93% ferrite) are successfully produced duplex stainless steels, while alloy 1 (10.18% ferrite) tends to be an austenitic stainless steel. The reduction fraction volume of ferrite is a function of: reduction of Cr/Ni ratio, increase of temperature, and length of holding time. The sigma phase appears at a temperature of 800 oC, while at temperatures of 400oC and 600oC the sigma phase does not appear.