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This study focuses on developing and validating a high-precision concurrent multi-scale finite element model considering the progressive damage model (PDM) and the cohesive zone model (CZM) for predicting the damage evolution of SiC f /Ti composites. At the macro-scale, a constitutive model describing the anisotropic damage criterion of SiC f /Ti composites was implemented by means of a user-defined subroutine (VUMAT). Meanwhile, based on the submodelling, a representative volume element (RVE) model was developed to systematically analyze the failure modes of the SiC fibers, the matrix, and the interface, respectively. Specifically, the crack initiation and propagation in the stress concentration zones were further discussed. Simultaneously, experimental methods were employed to verify the feasibility of the current model. During the uniaxial compression, the brittle fracture of the SiC fibers and ductile fracture of the matrix are the predominant failure modes of SiC f /Ti composites, with fiber fracture being the dominant factor. The crack initiates at the fibers, propagates rapidly to the fiber-matrix interface, and then extends into the matrix. Moreover, the fracture locations are suscepticle to stress concentrations, leading to the crack initiation and propagation. The predicted results show that the local damage has a significant effect on the failure mechanism of SiC f /Ti composites and this multi-scale model provides a scientific reference for the design and optimization of composites. • A high-precision concurrent multi-scale model is established to study the failure mechanism of SiC f /Ti composite. • The damage model based on the Hashin's criterion is developed by a user-defined material subroutine (VUMAT). • Failure modes of the SiC fiber, titanium matrix, and interface under compressive loading are systematically analyzed. • The simulation results closely match with the experimental results, filling the current research gap. [ABSTRACT FROM AUTHOR]

In this paper, continuous SiC fiber-reinforced Ti60 (SiC f /Ti60) composites were fabricated by preparing SiC f /Ti60 precursor wires from matrix-coated fibers and hot isostatic pressing (HIP) consolidation. The microstructures of the precursor wires and composites were investigated using XRD, SEM, EPMA, EBSD, and TEM, which led to the microstructure evolution of the composites. The conclusions of this study are as follows. 1. A reaction layer (RL) with a thickness of approximately 0.1 μm already exists at the interface of the precursor wires during the preparation. The HIP process accelerates the diffusion of the carbon coating with the Ti60 matrix, resulting in an increase in the thickness of the RL to approximately 0.5 μm. This layer is primarily composed of fine-grained TiC layer || discontinuous silicides || coarse-grained TiC layer. 2. The matrix of SiC f /Ti60 precursor wires contains α-Ti (∼ 1.9 μm), S2 (∼ 50 nm), and β-Ti (∼ 50 nm), in the matrix, β-Ti is precipitated from α-Ti, and HIP makes α-Ti, S2, and β-Ti grow to ∼ 2.4 μm, ∼ 200 nm, and ∼ 300 nm, respectively. 3. There are 〈0001〉//axial direction (AD) and 〈10−10〉//AD fiber textures in the matrix of the precursor wires, and HIP makes the matrix undergo a plastic deformation dominated by dislocation slip, and the pole density of the two kinds of textures are both increased. • Detailed study of precursor wires to SiC f /Ti60 composites interface and matrix microstructure evolution during hot isostatic pressing. • Sample preparation and characterization using advanced techniques such as FIB, EBSD, TKD, and TEM, etc. • During hot isostatic pressing, the reaction layer is transformed from fine-grained TiC to fine-grained TiC layer || discontinuous silicides||coarse-grained TiC layer. • During hot isostatic pressing, β-Ti and S2 silicides are precipitated from the Ti60 matrix, and the pole density of α-Ti changes. [ABSTRACT FROM AUTHOR]