#TITLE_ALTERNATIVE#

• Main Author: PARAMASTUTI (NIM : 13706023); Prof. Dr. Ir. Rochim Suratman dan Dr. Ir. Husaini Ardy, ANNISA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/14946
• Institution: Institut Teknologi Bandung

Repair welding of grey iron parts causing such cases in martensite formation in HAZ, also cementite formation in Weld Metal. These brittle structure can reduce the fracture toughness of both HAZ and Weld Metal. Flame Sray Coating is one of others method that can be used to repair a casting surface. This method uses oxyfuel flame to provide heat sources, which is used to melt the coating material. The coating process uses Nickel powder filler metal to provide high machinability in coating area of grey iron. When parts come in for repair, firstly it needs surface preparation, such as undercutting in order to provide a uniform surface to accept the new coating. The variety of notch are U-notch, Key-notch, and V-notch. Besides, it also needs <br /> <br /> <br /> <br /> <br /> controlling process parameters, such as acetylene and oxygen gas pressure, flow rate, preheat temperature, and standoff distance. To evaluate the quality of sprayed fusion area, microstructure observation and hardness test are applied. Microstructure observation shows that there are several defect in fusion area. The presence of these <br /> <br /> <br /> <br /> <br /> discontinuity reduce the bonding strength between filler metal and base metal. The mechanism by which thermal spray coatings bond to metallic substrates observed with only fusion-difusion characteristic. Specimen which is preheated up to 316oC with 10 mm standoff distance, provide a good adhesion bonding between filler metal and base metal. Both mechanical bonding and metallurgical bonding were occured <br /> <br /> <br /> <br /> <br /> in this specimen.