Synthesis, Physical, and Mechanical Properties of Bulk Zr₃Al₃C₅Ceramic

Abstract

An in situ reactive hot‐pressing process using zirconium (zirconium hydride), aluminum, and graphite as staring materials and Si and Y2O3 as additives was used to synthesize bulk Zr3Al3C5 ceramics. This method demonstrates the advantages of easy synthesis, lower sintering temperature, high purity and density, and improved mechanical properties of synthesized Zr3Al3C5. Its electrical and thermal properties were measured. Compared with ZrC, Zr3Al3C5 has a relatively low hardness (Vickers hardness of 12.5 GPa), comparable stiffness (Young's modulus of 374 GPa), but superior strength (flexural strength of 488 GPa) and toughness (fracture toughness of 4.68 MPa·m1/2). In addition, the stiffness decreases slowly with increasing temperature and at 1600°C remains 78% of that at ambient temperature, indicating that Zr3Al3C5 is a potential high‐temperature structural ceramic.

Microstructure and properties of hot pressed Zr2(Al(Si))4C5/SiC composites

“…The subscripts m and w refer to the matrix and the SiC particles, respectively. For Zr 2 A 4 C 5 /SiC composite, E m = 361 GPa, E w = 550 GPa,˛m = 7.6 × 10 −6 /K,˛w = 4.7 × 10 −6 /K, m = 0.19, w = 0.14 [12,15,17,18]. According to this model, a maximum radial compressive stress of about 1.3 GPa was introduced to the composites during cooling from 1900 • C to room temperature.…”

Isothermal oxidation of bulk Zr2Al3C4 at 500 to 1000 °C in air

“…Leela-adisorn et al 10 investigated the nonisothermal oxidation behavior of Zr 2 Al 3 C 4 samples with various densities and found that the oxidation resistance was improved when the density was increased. In addition, the oxidation resistance of Zr 3 Al 3 C 5 , which has similar crystal structure and properties to Zr 2 Al 3 C 4 , [8][9][10][11][12][13] is superior to that of ZrC in powder form. 14 Compared with ZrC, the improved oxidation resistance of Zr-Al-C ceramics is expected.…”

Effect of ball milled Zr/Al/ZrB2 composite powders on microstructure and toughening of ZrB2–SiC/Zr–Al–C composite ceramics sintered by spark plasma sintering

“…Additional Si powders (4 wt%) were added in raw powders before ball milling in order to promote the formation of Zr-Al-C compounds during the sintering process. Si could help the suppression or even removal of additional ZrC [23], and Si atoms would exclusively occupy the site of Al thus a small amount of Si dissolved into Zr 2 Al 4 C 5 forming a stable solid solution [24]. The weight ratio of ball to powder is 10:1 and the milling process is under an argon atmosphere.…”