Thermochemical study of boron suboxide B6O

Liquid phase assisted hot pressing of boron suboxide-materials

“…The determined enthalpy of formation of B 6 O agrees with other values for similar compounds such as B 6 Si, B 6 As, and B 6 P. 11 Also the C p values near room temperature are quite close to the C p values of B 6 Si ( Fig. 1).…”

“…However, no data concerning the dependence of thermodynamic data on the oxygen content in B 6 O are known. The determination of the thermodynamic data [11][12][13] was carried out on materials produced at ambient pressure, and therefore it can be assumed that they have a similar non-stoichiometry as the powders used in this investigation.…”

“…15 = 39.91 J/(mol K) and the enthalpy of formation as H θ f (B 6 O, s, 298.15 K) = −527 ± 32 kJ mol −1 . 11 The temperature dependent heat capacity was established for the temperature range 298.15-800 K as C p = 54.55936 + 17.263 × 10 −2 T −28.2 × 10 5 T −2 (J/(mol K)) 12 (1)…”

“…A possible way for predicting the phase formation in B 6 O composites during sintering is the thermodynamic calculation of the equilibrium phases. However, current knowledge on the thermodynamic properties of boron suboxide is limited to temperatures of up to 800 K. [11][12][13] The entropy was determined to be S 298. 15 = 39.91 J/(mol K) and the enthalpy of formation as H θ f (B 6 O, s, 298.15 K) = −527 ± 32 kJ mol −1 .…”

Liquid phase assisted densification of superhard B6O materials

“…Additives (wt%) 20 i.e. the measured data reveal a lower stability of B 6 O than the estimated data of McMillan.…”