Maximum cooling rate of quenching medium temperature (℃/S) 300℃ cooling rate (℃/S)
Water 35℃ 22 1 102.4
Haiyi water-based quenchant 5% 35℃ 205 87.9; 10% 35℃ 170 6 1.4; 20% 35℃ 129 36.8
K oil 50℃10114.0
G oil 50℃ 92 6.5
No.2 engine oil 50℃ 73 1 1.5
As can be seen from the above table, the cooling rate of water-soluble oil quenching liquid with concentration below 20% is between water and oil. The cooling capacity of different concentrations can be seen from the following data:
40# steel, hardness unit HRC
Quenching medium φ 38.1mm φ 25.4 mm φ12.7 mm.
Surface hardness core hardness surface hardness core hardness surface hardness core hardness
Water 5 1 30 54 33 55 46
Rapid quenching oil 28 20 43 20 45 20
Medium speed quenching oil 23 20 38 2 1 4 1 20
Water soluble oil quenching solution: 5% 50 28 53 365 438+0 55 45; 10% 49 25 5 1 28 52 3 1; 20% 32 23 38 25 4 1 25; 35% 28 20 35 2 1 39 20 30CrMo steel,
Hardness unit HRC
Quenching medium φ 25.4 mm φ 19. 1 mm
Surface hardness, core hardness, surface hardness, core hardness
Water 5 1 43 53 52
20% 40 38 49 49
Quenching oil 42.36 38-32 5 1-47 49-42
42rMo steel, hardness unit HRC.
Quenching medium φ38. 1 mm φ 9.5mm.
Surface hardness, core hardness, surface hardness, core hardness
water
20% 53 52 60 59
Rapid quenching oil 53 47 59 58
Medium speed quenching oil 50 43 57 55
Steel grade suitable for ship quenching with water-based quenching medium: carbon steel and alloy steel with high hardenability.
Low, medium and high carbon steel, large section, complex thin section.
Quenching strength H of nitriding steel and carbonitriding steel
Medium-low carbon low alloy steel 5 2 0.9 0.7 0.5 0.3 0.2
Low permeability steel brine, quick oil, medium oil, conventional oil and hot oil.