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Metal-Ceramic Functionally Graded Materials (FGM) find extensive applications in nuclear power generators, spacecraft systems, and energy conversion systems. This study aims to investigate the behavior of FGMs under transient thermal loads and time-dependent mechanical loads through finite element modeling. A 2D model is developed using COMSOL Multiphysics to simulate the behavior of a metal-ceramic FGM thick cylinder. The model considers Titanium-Zirconium-Molybdenum (TZM) alloy for metals and Silicon carbide (SiC) for ceramic. It accounts for the effects of transient thermal loads and internal time-dependent pressure exerted on the cylinder's inner surface. Thermo-mechanical properties, assumed to follow an exponential function, are incorporated into the model. Numerical analysis results are compared with established analytical solutions to validate the model. Graphical comparisons between numerical and analytical results demonstrate significant agreement, confirming the reliability of the numerical approach. This study provides insights into the behavior of metal-ceramic FGMs under transient thermal and mechanical loads. The findings underscore the effectiveness of finite element modeling in understanding complex interactions within FGMs. Future research directions include exploring more complex geometrical models, incorporating additional loading scenarios, and performing experimental validation to enhance understanding of FGM performance in real-world conditions.

Equal Channel Angular Pressing (ECAP) is a promising severe plastic deformation technique that has gained significant attention for its ability to refine grain structure and enhance mechanical properties in metallic materials. This study focuses on investigating the impact of ECAP with route A and up to three passes on the mechanical properties and microstructure of 1050 aluminum. The study yielded compelling evidence of substantial enhancements in yield strength, ultimate tensile strength, and hardness. Specifically, these properties increased from 58.19 MPa, 67.06 MPa, and 23.85 HV in the annealed state to 133.02 MPa,141.21 MPa, and 38.96 HV after the third pass of the ECAP process, respectively. Furthermore, an interesting observation was made regarding the hardness ratio, which demonstrated a noticeable decrease with an increasing number of ECAP passes. This phenomenon correlated with a reduction in the size of dimples on the fracture surface. Microstructural analysis via scanning electron microscopy SEM confirms a significant reduction in grain size after ECAP passes, indicating the effectiveness of the process in inducing microstructural refinement. These findings collectively underscore the potential of ECAP with route A in enhancing the mechanical properties and microstructure of 1050 aluminum. This research contributes valuable insights into the application of ECAP with route A as a viable strategy for improving the performance of aluminum alloys.

Assessing the structural integrity of a cracked weldment is crucial. Cracks detected during welding inspections must be examined in the context of the structure's mechanical resistance. Generally, fracture mechanics supplies essential tools to determine a fracture criterion for loading conditions. This study explores the effect of residual stress (RS) and crack orientation on determining the stress intensity factor (𝐾 ) for a welded joint using the extended finite element method. This study comprises a 3D thermo-mechanical finite element (FE) analysis to study the temperature history and the residual stress distribution of a welded joint, and a 3D FE crack model that considers two cases of cracks—longitudinal (case I) and transverse (case II)—to calculate the 𝐾 value at the middle surface of a thin butt joint. 𝐾 is calculated for cracks under applied external and residual stresses. The results demonstrate that the welding residual stress can beneficially or detrimentally affect 𝐾 depending on stress distribution and sign, and indicate the significance of RS and crack orientation on 𝐾 . Simulation results demonstrate that the longitudinal crack in case I has higher 𝐾 values than those in case II for the transverse crack and show good agreement with the analytical results.