Thermal Shock Test of Ceramics by Helium Gas Cooling through a Narrow Slit

概要

論文の詳細を見る
In order to evaluate the reliability of ceramics under transient thermal stress, thermal shock test equipment was designed and fabricated. Cylindrical specimens made of Si_3N_4 and SiC were tested by the test equipment. Each specimen was preheated uniformly at 1573 K in an electric furnace and then pulled down rapidly into a cooling chamber beneath the furnace. At the same time, it was cooled locally by high-velocity helium gas that was passed through a narrow slit. The transient temperature distributions were measured by optical pyrometers and thermocouples. The moment of fracture was confirmed by the sound of the fracture itself. Fracture originated at the outer surface immediately under the cooling nozzle. Consequently, the average value of nondimensional fracture stress of Si_3N_4 specimens was about two times that of SiC specimens.
一般社団法人日本機械学会の論文
2002-10-15