Impact Fatigue Life Prediction for Notched Specimen of Steel AerMet100 Subjected to High Strain Rate Loading

Abstract

In this study, the ultra-low cycle fatigue (ULCF) behavior of a high-strength-ductile steel AerMet100 exposed to repeated high strain rate impact loadings is investigated. Three types of coupon-level experiments were performed, in which a three-point bending (TPB) specimen with a through-thickness notch was employed for multi-impact test. A special ratchet effect associated with complex stress state, dynamic impact loading and other physical mechanisms was observed through measured principal strain variations with a specific decay rate at the notch root surface. An improved ULCF predictive model based on the continuum damage mechanics was developed to quantify the relationship between the fatigue damage and the input of localized impact energy to the notch root. The model expressed in terms of damage growth rate introduces a new exponential term for better predictive accuracy and reduced number of nonlinear dynamic response analysis. As a computational efficient tool, the proposed model can predict impact fatigue life in acceptable timeframe for multiple critical locations in a complex engineering component.

Modeling the Transient Dynamics of Arresting Hooks and Cables through the Parameter Inversion Method

“…The outer structure of the arresting hook is shown in Figure 8. The hook arm material of the arresting hook is AerMet 100 steel, and its related parameters [21] are shown in Table 3. The arresting hook possesses intricate structural characteristics, with element types including C3D8R and C3D4, whereas the element at the hook arm is a C3D8R.…”

Fatigue life prediction of aircraft gun cabin structure under impact

“…Rajendran et al [2] reviewed the research results, including the characteristics of blast wave propagation in air and underwater, the fluid-structure interaction between blast wave and plates, the plastic deformation and fracture of metal plates under blast wave, etc. The impact fatigue exists in many engineering problems and has been studied to some extent [3][4] . However, the theories are still immature, and the key issues such as impact damage mechanism and damage evolution law are still unclear.…”