Abstract :
This research was conducted to determine the effect of heat treatment with
variations media quenching of water, radiator coolant, and oil and also the effect
of tempering after quenching on tensile strength and microstructure of carbon
steel currently. The heat treatment process begins with customization at a
temperature of 900°C for 45 minutes then quenched with variations of water,
radiator coolant. After that, the oil was tempered at 450°C for 90 minutes.
The results of the study show that the variation of quenching media affects
the value of tensile strength and microstructure. On the microstructure of the
specimen water quenched tends to form sharp and firm martensite so that it has an
average maximum tensile strength of 1,594.19 and strain of 1.85%. Radiator
coolant and oil quenching media have almost similar microstructure but have an
average tensile strength value which differs in maximum stress of 1,209.99 and
1,123.58 and strain of 0.47% and 1.61%.
The tempering process results in the decomposition of martensite so that
the microstructure changes and is more dominated by pearlite and ferrite making
the value tensile strength decreases. The average tensile strength value of water
quenching media maximum stress was 1117.46 and strain 12.71%, quenching
Radiator media coolant maximum stress 1,083.47 and strain 13.46%, and oil
quenching maximum stress 774.87 and strain 12.35% after receiving the process
tempering.