Analisis Variasi Interpass Temperature dan Arus Pengelasan pada Pengelasan Hardox 450 terhadap Nilai Kekerasan, Nilai Ketangguhan dan Struktur Mikro

Abstract

The more technology develops, the demand for steel and iron specifications is increasingly
diverse. One of the steels that are often used in the industrial world is Hardox steel. In the case of PT.
X in FCAW welding uses excessive current welding and the interpass temperature is not applied
properly. So that in this study the authors will conduct experiments on the impact of variations in
welding currents at 120A and 200A amperage and interpass temperatures at 150°C and 200°C on
Hardox 450 material on welding results in terms of hardness, toughness and microstructure. The
results of this study for hardness testing experienced an increase in the increasing current variation
but a decrease in the increasing interpass variation. The highest hardness was found in specimens
with variations of 150°C and 200A with an average value of 204.2 kgf/mm 2 in the weld metal area
and in the HAZ area with an average value of 287.03 kgf/mm 2 . Then in the highest toughness test
found in specimens with variations of 200°C and 120A with an average value of 123 J in the weld
metal area and in the HAZ area with an average value of 103 J. The micro test results show that the
higher the interpass produces an even acicular ferrite structure and the higher the current, the denser
the pearlite structure is.