With the help of steel wire probes, the cooling curves of steel wires upon patenting in lead bath and alternatives were measured, and the cooling characteristics and the austenitic transformation process of the wires upon patenting were analyzed. Experiment results showed that patenting in lead bath was not an isothermal process, austinite transformation completed in a fluctuated temperature range before wire got to bath temperature. The appropriate CMC polymer aqueous solution and water spray fields could also produce the pearlite microstructures without separation of primary ferrite for high-carbon steel wires, but the cooling behaviors were controlled by the inherent "thermal barrier" on the cooling interface involved in aqueous quenchants which possess of much lower thermal diffusion ability than lead bath. It must be noticed, therefore, that it is the coherence of the "mass effect" of steel wires and the cooling characteristics of quenchants that determines the microstructure upon patenting, which contributes to a better understanding of alternatives for patenting process and provides a basis for laying down alternatives' variables upon patenting.
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