Microstructure and thermophysical properties of B4C/graphite composites containing substitutional boron
writer：Wang H Q, Guo Q G, Yang J H, Zhao Y, Wang X L, Tao Z C, Liu Z J, Feng Z H, Liu L
keywords：boron, graphite
source：期刊
specific source：Carbon, 2013, 52(2): 10-16.
Issue time：2013年
B 4 C/graphite composites (BGC) containing substitutional boron were fabricated by pressureless sintering of powder mixtures of petroleum coke, coal tar pitch and B 4 C. After sintering at 900 C and graphitizing at 2200 C, the microstructure of BGC was characterized by SEM, TEM, XRD, Raman spectroscopy and optical microscopy. XPS measurements revealedthe formation of BC 3 , and the matrix carbon contained around 6 wt.% substitutional boron.The thermal conductivity of the BGC at room temperature is 52.7 W/m K and the ?exural strength is up to 35.1 MPa. The bulk density and electrical resistivity are 1.72 g/cm3 and 13.4 lX m, respectively. The correlation between microstructure and properties was investigated. The results showed that the microstructure improvement of the BGC has obvious effect on the thermal conductivity, ?exural strength, and electrical resistivity.