Modeling creep and fatigue of copper alloys

This article reviews expressions to quantify the thermal creep and fatigue lifetime for four copper alloys: Cu-Ag-P, Cu-Cr-Zr, Cu-Ni-Be, and Cu-Al2O3. These property models are needed to simulate the mechanical behavior of st ructures with copper components, which are subjected to high heat-flux and fatigue loading conditions, such as molds for the continuous casting of ste el and the first wall in a fusion reactor. Then, measurements of four-point bending fatigue tests were conducted on two-layered specimens of copper al loy and stainless steel, and thermal ratchetting behavior was observed at 2 50 degrees C. The test specimens were modeled with a two-dimensional elasti c-plastic-creep finite-element model using the ABAQUS software. To match th e measurements, a primary thermal-creep law was developed for Cu-0.28 pet A l2O3 for stress levels up to 500 MPa and strain rates from 10(-8) to 10(-2) s(-1). Specifically, (epsilon) over dot (s(-1)) =1.43 x 10(10) exp (-197,0 00/8.31 T(K)) (sigma(MPa))(2.5) (t(s))(-0.9).