Cooling power of quenchants based on water-soluble polymers

摘要

The effects of the concentration of the polymer quenchant, the bath temperature, and agitation on the cooling power of water-based solutions of polyethylene glycol at different molecular weights (PEG-3000, PEG-6000 and PEG-10000) have been investigated. The quenching characteristics of these aqueous polymer quenchant solutions have been determined by means of the cooling curves: T(°C) =f(t), and of the cooling rate curves: T(°C) =f(rate), during the quenching of a cylindrical test probe, made of Inconel 600 (ISO/DIS 9950) in an adequate quench bath. The results have shown that the cooling power increases with agitation, but decreases with increasing temperatures and polymer solutions' concentrations. The variation of these experimental parameters affects significantly the three quenching mechanism steps (vapour blanket, boiling, and convection step).