Metallurgical behaviours of high-carbon steel wires in lead bath and CMC aqueous solutions by cooling curve analysis

The cooling process of 0.70% carbon steel wires upon patenting in lead baths and CMC (Carboxyl Methyl Cellulose) aqueous solutions was measured respectively with the steel wire probes. The cooling process and the transformation behaviours of the wires, upon patenting, were interpreted by cooling curve analyses. It is the coherence of the 'mass effect' of steel wires and the thermal diffusion ability in cooling media that dominates the patenting process and the transformation behaviours of the wires. The high carbon steel wires could fulfil the transformation to pearlite in the 0.25% CMC aqueous solution. But the transformation temperature is higher than that in lead patenting due to its attribution of continuous cooling transformation. According to the cooling essence for patenting and the cooling characteristics of the CMC aqueous solutions, the adoption of the alternative should be focused on accelerating the cooling of the primary stage for patenting.