Comparison of High Purity Fine Grain Graphites from Different Suppliers with Regard to Physical, Mechanical, and Thermal Properties

摘要

Thermal shock resistance of eight fine grain graphites was tested in single shot experiments in an electron beam welding machine. A carbon fiber composite material was also tested. Apparent density; total and open porosity; electrical resistivity between room temperature and 1000 C; thermal conductivity between 100 and 1000 C; linear thermal expansion between room temperature and 1000 C; dynamic Young's modulus; and bending strength and fracture deflection were determined. Materials EY-306, FP-219, and E-5923 P (electron beam vertical to the fiber planes) show the highest weight loss values. Relatively low amounts of eroded material in all series are found for EK 98, ATJ, FE-289, and E-5923 P (electron beam parallel). The graphite AXF-5 Q shows the worst cracking behavior, followed by EY-306. Excellent thermal shock behavior is detected for the materials FP-219, ATJ, and the carbon fiber composite E-5923 P.