Microstructure evolution of interface and matrix during the preparation of SiCf/Ti60 composites.

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]