izvorni znanstveni rad
Analysis of the quenching oil’s cooling curves with agitation and with addition of nanoparticles
Sažetak
The main goal of the investigation is to define the quenching characteristics of standard quenching oil with ultrasonic agitation and addition of nanoparticles. The tested quenching oil was Fuchs Thermisol QH 120. The tested quenchant temperatures were set at 20 and 60°C. This oil type was previously tested within the Liquid Quenchant Database project. Two methods of heat transfer dynamics enhancement were investigated: agitation using ultrasonic bath and the addition of high thermal conductivity nanoparticles. Bath parameters were frequency of 50 kHz and 120 W of power achieving pressure waves from 50-200 kPa.. Nanoparticles of TiO2 were added to the oil in order to increase thermal conductivity and heat transfer characteristics of the oil. All of the cooling curves were measured, recorded and evaluated by IVF SmartQuench system using Inconel 600 probe with 12.5 mm diameter in accordance with ISO 9950 standard. Cooling rate vs. temperature and time was compared for all of the investigated media, as well as the heat transfer coefficient (HTC). The effect of quenchant temperature, nanoparticle concentration and ultrasonic agitation on the cooling characteristics was investigated.
Ključne riječi
Quenching; ultrasonic agitation; nanoquenchant; oil