The Possibility of Correlation of Hardening Power for Oils and Polymers of Quenching Mediums

Table 3

Summary of quenchants and quenching conditions.

Parameters	5% aqueous		25% aqueous		Conventional quench    oil OH70	High temper oil Mar-Temp 890
	polymer solution		polymer solution
	1	2	3	4	5	6
Quench bath temperature [^∘C]	30	30	30	30	60	100
Agitation rate [m/s]	0.24	0.52	0.24	0.52	0.51	0.52
V550 [^∘C/s]	47.6	46.3	31.4	37.6	35.2	36.9
V330 [^∘C/s]	26.8	30.1	18.6	24.5	19.8	20.7
𝑇vp^1 [^∘C]	831	823	774	800	834	828
𝑇cp^2 [^∘C]	89	78	179	109	132	159
Time for nucleate boiling to begin [s]	33	31	19.2	32.2	34.7	31
HP1^3	1380	1404	768	1153	1082	990
HP2^4	330	371	172	266	199	217
Core hardness (HRC)^5	35	37	21	21	21	25
Core hardness (HV0.1)	367	370	310	299	317	365

(1) 𝑇_VP is the transition temperature in (^∘C) between the film-boiling (vapor-cooling) stage and the nucleate boiling stage of the cooling process.
(2) 𝑇_CP is the transition temperature (^∘C) between the nucleate boiling stage and the convective cooling stage of the cooling process.
(3) Hardening power (HP) was calculated using the Bodin-Segerberg equation for unagitated oils: HP = 91.5 + 1.34 × 𝑇_VP + 10.88×𝑉500 − 3.85 × 𝑇_CP.
(4) Hardening Power (HP) was calculated (2) developed for agitated polymerquenchants; HP = 3,54 ×𝑉550 + 12.30 ×𝑉330 − 168.
(5) The core hardness values were determined on the 1045 steel test specimens quenched as shown in the table. These hardnesses were determined after quenching.