Discontinuous precipitation in a Cu-10Ni-1Si alloy with ultra-high strength, high shock absorption, and good stress relaxation resistance

The discontinuous precipitation in a Cu-10Ni-1Si alloy aged at 500 degrees C and 550 degrees C was studied to clarify the types of discontinuous precipitates, and the crystal relationships between precipitates and the matrix. The continuous delta-Ni2Si precipitates were detected in the initial aging stage, then discontinuous beta-Ni3Si and continuous delta-Ni2Si precipitates were detected simultaneously. The crystal relationship between dis-continuous beta-Ni3Si precipitates and the copper matrix at the beginning of aging was that: (111)Cu//(111)beta, [011]Cu//[011]beta. The lamellar discontinuous beta-Ni3Si precipitates significantly improve stress relaxation re-sistance and damping properties, which are attributed to the interaction between lamellar structure and dislocation motion. These findings indicated that the formation of the lamellar discontinuous precipitates tends to prevent dislocation slip and promote precipitation, resulting in enhanced mechanical properties and conductivity properties simultaneously. (c) 2022 Elsevier B.V. All rights reserved.

Automated summary

The study investigates the discontinuous precipitation in a Cu-10Ni-1Si alloy aged at 500 degrees C and 550 degrees C, aiming to identify the types of precipitates and their crystal relationships with the matrix. Continuous delta-Ni2Si precipitates are initially detected, followed by the simultaneous detection of discontinuous beta-Ni3Si and continuous delta-Ni2Si precipitates. The crystal relationship between discontinuous beta-Ni3Si precipitates and the copper matrix is found to be (111)Cu//(111)beta, [011]Cu//[011]beta in the early aging stage. The lamellar discontinuous beta-Ni3Si precipitates significantly improve stress relaxation resistance and damping properties, attributed to the interaction between the lamellar structure and dislocation motion. These findings indicate that the formation of lamellar discontinuous precipitates hinders dislocation slip and promotes precipitation, leading to enhanced mechanical and conductivity properties.