Associate professor, Third University of Rome, Rome,
Research engineer, Rome University “La Sapienza,”, Rome,
Advanced titanium alloy metal matrix composites offer significant mechanical improvements over many conventional materials. In order to minimize fiber-matrix chemical reactions due to high temperatures involved in the fabrication methods, the final component can be obtained using two different steps: (1) fabrication of preforms (monotapes) by inert plasma spraying and (2) hot pressing of the fabricated preforms.
Continuous SiC fiber-reinforced Ti-6Al-4V preforms were hot pressed to fabricate a composite multilayer. Different values of hot pressing processing parameters (temperature, applied load, bonding time) were investigated on the basis of a two-level factorial design. Metallographic and scanning electron microscopy (SEM) analyses were carried out to evaluate the bonding degree of the fabricated preforms. Preliminary three-point bending tests were also performed to understand the mechanical behavior and to show the more suitable values of the processing parameters for a hot pressing procedure. These values should be in the range of 830 to 950°C (temperature), 80 MPa (applied stress), 20 to 30 min bonding time to avoid undesired phase transformation, large plastic flow of the metal matrix, and detrimental chemical reaction at fiber-matrix interface.
Paper ID: CTR10519J