ISSN: 0884-6804
Page Count: 7

Hot Pressing of Plasma-Sprayed SiC Fiber-Reinforced Ti-6Al-4V Alloy
Carassiti, F
Associate professor, Third University of Rome,

Valente, T
Research engineer, Rome University “La Sapienza,”,

Abstract

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.

Keywords:
metal matrix composites, inert plasma spraying, hot pressing, factorial design, silicon-carbide fibers, titanium alloy matrix

Paper ID: CTR10519J
DOI: 10.1520/CTR10519J
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