沥青基碳纤维热导率的间接法测量

Testing of Thermal Conductivity of Pitch-Based Carbon Fibers by Indirect Test Method

文摘采用"四探针法"测定6种沥青基碳纤维单丝的轴向电阻率,通过3个经验公式计算得到其热导率,再将计算值与厂商公布值进行对比分析。结果表明:对于热导率>600或<300 W/(m·K)的碳纤维采用公式λ=1261/ρ计算得到的热导率值与厂商公布值最为吻合,而对于热导率在300~600 W/(m·K)的碳纤维采用公式λ=440 000/(100ρ+258)-295计算得到的热导率值与厂商公布值最为吻合。以此测试值为基础,建立了沥青基碳纤维单丝电阻率与其热导率的函数关系λ=152 740/(100ρ+22)-26,具有更强的普适性。

The axial electrical resistivity of individual pitch-based carbon fiber of six kinds carbon fibers was measured by a four-probe method.The thermal conductivity values were calculated by different empirical formulas, re- spectively and the calculated values were compared with the published values.The results show that the thermal conduc- tivity values calculated from the formula λ = 1261/p are consistent with these pitch-based carbon fibers with thermal con- ductivity over 600 or less than 300 W/（ m·K）.For the pitch-based carbon fiber that thermal conductivity is between 300 and 600 W/（m·K） ,its calculated thermal conductivity based on the formula λ =440000/（100ρ＋258） -295 is more ac- curate.Based on this test, the relationship between the electrical resistivity of individual pitch-based carbon fiber and its thermal conductivity is established as λ= 152740/（100p＋22）-26,which has stronger universality.