Abstract
The transformation of α and β phases during the tempering of a quenched hypo-eutectoid Cu-Be alloy has been studied.
Water quenched specimens were tempered and subjected to microhardness, micrographic and X-ray measurements.
The results obtained were as follows:
(1) On tempering below 350°C, the α and β phases harden almost in parallel with each other, while on tempering at 400°C hardening of the β phase is accelerated followed by appreciable softening.
(2) High temperature X-ray diffraction results indicate that on heating from room temperature, the initial transformation process is due to an eutectoid reaction of the β phase and decomposes almost completely when the specimen reaches 300°C, while the precipitation within the coexisting α region still proceeds throughout the 60 minutes holding at 300°C.
(3) Transformation in α and β phases takes place almost independently of each other in each grain and grain boundary, and there is no positive evidence that the grain boundary precipitation of the α phase is promoted by the eutectoid decomposition of the β phase at the α-β interface.
