STUDY OF EFFECT OF HEAT INPUT ON MECHANICAL PROPERTIES AND MICROSTRUCTURE OF RESISTANCE SPOT WELDING UNS N06600 ALLOY

• Main Author: Mahfuzh (13714021), Abdul
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/24897
• Institution: Institut Teknologi Bandung

<p align="justify">Resistance spot welding is one of welding types that is still used today because of its advantages, such as: cheap, can be carried out on various types of materials and thicknesses, short cycle times, and does not require filler metals. Joining of metals with RSW is caused by melting of metal due to heat input given to the plate. Parameters affecting heat input are electric current, resistance, and welding time. This study aims to determine the effect of heat input on mechanical properties, width of nugget and HAZ, as well as the characteristics of microstructure from the results of RSW welding of UNS N06600 material. Welding is done by a varied currents of 9.11.13kA and welding time of 1.3.1.5s. The tests carried out were chemical analysis, tensile shear tests, hardness testing, and metallographic testing. From this study it can be seen that due to the parameters given will produce an expulsion of metal welds. Expulsion will reduce the weld strength from 621 MPa to 519 MPa. The increase in heat input from 23 kJ to 56 kJ will increase the nugget size from 2.8 mm to 4.2 mm and the HAZ from 179 to 435 &#956;m. Hardness value is different for each RSW welding zone with an average hardness of 172 HV metal base, HAZ 165 HV, and 170 HV in nugget. In addition, there was a phenomenon of growth of wheat grains in the HAZ region, the form of cellular dendritic grains, dendritic in areas that formed heat flow during the solidification process and the formation of Cr7C3 carbide in the nugget area.<p align="justify">