ANALISIS PENGARUH HOLDING TIME ARTIFICIAL AGING DENGAN PENGELASAN GTAW PADA ALUMINIUM ALLOY 6061 TERHADAP SIFAT MEKANIK DAN METALLOGRAPHY TEST

Abstract

Aluminum is one of the most widely used non-ferrous metals in the engineering field because it has
lightweight, corrosion-resistant, and recyclable properties To meet the eligibility of bicycles for sale, bicycle
frames must have a hardness value of 16-17 HRE (112-142 HVN). However, initially this material has a
hardness value of 4-6 HRE, therefore it is necessary to do heat treatment after welding or it can also be called
PWHT. This research was conducted to find the effect of holding time artificial aging on tensile value,
microstructure, and hardness. The tensile test results show that the highest average nikai is at the holding time
artificial aging 4 hours, which is 250.93 Mpa. The microstructure test results show an increase in the number
of Mg2Si phases and the denser the microstructure if it is at the right holding time.. In microstructure testing,
specimens with holding time artificial aging 4 hours have the most Mg2Si structure so that it is homogeneous
so that it has the highest average hardness as well. The hardness test results show that the highest value is in
the base metal with a holding time of artificial aging 3 hours, which is 133.80 HVN and the lowest in the
specimen with a holding time of 5 hours, which is 116.2 HVN. Especially in the weld metal area, the highest
hardness is in the specimen with a holding time of 4 hours, which is 95.3 HVN and the lowest hardness value
is in the specimen with a holding time of artificial aging 5 hours, which is 82.2 HVN. So it can be concluded
that with the influence of the right holding time can increase the value of hardness and improve the final
structure of the material.