Influence of vacuum hot-pressing temperature on the microstructure and mechanical properties of Ti–3Al–2.5V alloy obtained by blended elemental and master alloy addition powders

SiC whisker-reinforced ZrB2 matrix ultra-high temperature ceramic were prepared at 2000°C for 1 h under 30MPa by hot pressing and the effects of whisker on flexural strength and fracture toughness of the composites was examined. The flexural strength and fracture toughness are 510±25MPa and 4.05±0.20MPa⋅m1/2 at room temperature, respectively. Comparing with the SiC particles-reinforced ZrB2 ceramic, no significant increase in both strength and toughness was observed. The microstructure of the composite showed that the SiC whisker was destroyed because the SiC whisker degraded due to rapid atom diffusivity at high temperature. The results suggested that some related parameters such as the lower hot-pressing temperature, a short sintering time should be controlled in order to obtain SiC whiskerreinforced ZrB2 composite with high properties.

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Influence of Hot Pressing Temperature and SiC Content on the Microstructure and Mechanical Properties of ZrB2-SiC

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.434-435.189 ◽

2010 ◽

Vol 434-435 ◽

pp. 189-192

Author(s):

Yong Zhang ◽

Ping Hu ◽

Xing Hong Zhang

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Flexural Strength ◽

Hot Pressing ◽

Volume Percent ◽

Pressing Temperature ◽

Sic Ceramics ◽

Opposite Trend ◽

Microstructure And Mechanical Properties ◽

Dense Ceramic

The influence of hot pressing temperature and SiC content on the microstructure and mechanical properties of ZrB2-SiC ceramics was investigated. ZrB2 containing 20 volume percent SiC were prepared by hot pressing at 1850, 1900 and 1950°C for 60 min. Fully dense ceramic was obtained after hot pressing at temperature of 1950°C. In addition, the materials with SiC content of 0, 10vol.%, 15 vol.%, 20 vol.% and 30 vol.% hot pressed at 1950°C were also investigated. Results showed that the grain size of the ZrB2 significantly reduced on adding 10vol.% SiC and then decreased slightly with further increasing SiC content, whereas the grain size of SiC exhibited a opposite trend. The flexural strength of ZrB2-SiC ceramics remarkedly increased on adding 10vol.% SiC due to the significant decrease of ZrB2 particle size and then slightly increased with increasing SiC content up to 20vol.%. However, further increasing SiC content led to a reduction of the flexural strength.

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Effect of Processing Condition on the Microstructure and Mechanical Properties of Ti3SiC2/SiC Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.658.352 ◽

2010 ◽

Vol 658 ◽

pp. 352-355 ◽

Cited By ~ 3

Author(s):

Hong Feng Yin ◽

Lin Lin Lu

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Flexural Strength ◽

Hot Pressing ◽

Processing Condition ◽

High Porosity ◽

Pressing Temperature ◽

Pressing Method ◽

Microstructure And Mechanical Properties ◽

Sic Composites

Ti3SiC2/SiC composites were fabricated by reactive hot pressing method. Effect of processing condition on the microstructure and mechanical properties of the composites were investigated. The results showed that: (1) Hot-pressing temperature influenced the phase constituent of Ti3SiC2/SiC composites. The flexural strength and fracture toughness of composites increased with hot pressing temperature. (2) The flexural strength and fracture toughness of composites increased when the content of SiC was increased. When the SiC content was 30wt% the flexural strength and fracture toughness of Ti3SiC2/SiC composite were 371MPa and 6.9MPa•m1/2 respectively. However, when the content of SiC reached 50wt%, the flexural strength and fracture toughness of composites decreased due to high porosity in the composites. (3) The flexural strength and fracture toughness of composites increased with the particle size of SiC added in composites. (4) Ti3SiC2/SiC composites were non-brittle at room temperature.

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