PENGARUH ARUS DAN WAKTU PENGELASAN TERHADAP STRUKTUR MIKRO, KEKERASAN, DAN DUCTILITY SAMBUNGAN LAS TITIK

Abstract

In the beginning, designing and building home industry spot welding (SIR) is an alternative that can be used to joining two sheet of plate with electrical power in house (900 Watt) for that application, as while as this time spot welding machine is just used in industry (such as car body shop industry). However, the performance of SIR is experimentless, so that it’s very important to knowing that from research about current and welding time effect for SIR nugget quality. The analysis is about microstructure observation, diameter, hardness testing, and ductility of nugget. To compare SIR, TECNA spot welding machine (fabrication from industry) is can be used. The purpose of the research is to get the optimum nugget that appropriate with a base metal by microstructure observation, diameter of nugget, hardness, and ductility. The research is by using the SIR spot welding with current 475 A and using 7 second and 35 second of welding time. To compare that, TECNA spot welding machine can be used, by current 5000 A and welding time is 2 second. By variating current and welding time, we can get a different result. From microstructure of nugget observation, nor 7 second and 35 second on SIR, the joining is’nt produced. That is can be caused by low current until heat is’nt enough to joining the two sheet of plate. Whereas, with TECNA spot welding machine, for 2 second welding time, nugget can be produced. The research was did, and we can conclude that with high current that appropriate with base metal, and the faster of welding time can be produce an optimum nugget quality. That’s can be observation from microstructure, diameter, hardness, and ductility that more optimum.