Several tungsten nickel cobalt alloys were evaluated for quench sensitivity by subjecting them to cooling rates from 18 °C/sec to 72 °C/sec. Tensile properties were then measured to determine the effect of the cooling rate on the alloy. The testing revealed that the alloys with a 0.11 Cobalt to Nickel ratio exhibited a critical quench rate while the alloys with 0.43 and 0.5 ratio did not. This relationship appeared not to be related to tungsten content as both the 90 and 91.25 weight percent tungsten alloys were sensitive to quench rate. The value of 34 °C/s was found to be the minimum necessary quench rate to achieve full tensile ductility potential from all the alloys in the study. Based on the data a model was developed and the resulting analysis indicated that alloys with a Cobalt to Nickel ratio above 0.2 would not show any quench sensitivity.
展开▼
