ASTM D6200 Determination of Cooling Characteristics of Quench Oils
ASTM D6200 Standard Test Method for Determination of Cooling Characteristics of Quench Oils by Cooling Curve Analysis
4. Summary of Test Method
4.1 Determine the nickel alloy probe assembly's cooling time versus temperature after placing the assembly in a furnace and heating to 850°C (1562°F) and then quenching in a heat treating oil. The temperature inside the probe assembly and the cooling times are recorded at selected time intervals to establish a cooling temperature versus time curve. The resulting cooling curve may be used to evaluate quench severity (see Note 1).
NOTE 1 - For production testing, the furnace temperature of 815 to 857°C (1500 to 1575°F) may be used.
5. Significance and Use
5.1 This test method provides a cooling time versus temperature pathway which is directly proportional to physical properties such as the hardness obtainable upon quenching of a metal. The results obtained by this test may be used as a guide in heat treating oil selection or comparison of quench severities of different heat treating oils, new or used.
6. Interferences
6.1 The presence of water in a heat treating oil has a major effect upon the results obtained with this test method. Water content of calibration fluids shall be confirmed by Test Method D1744. If water is present above 0.01 %, the calibration fluid shall be dried at a minimum temperature of 102°C (216°F) until Test Method D1744 indicates water content at or below 0.01 %.
