Development of an equipment for detecting trace amounts of gases evolved from ceramic materials during fractur

1996 Fiscal Year Final Research Report Summary

• Project/Area Number: 07505017
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 試験
• Research Field: Inorganic materials/Physical properties
• Research Institution: The University of Tokyo
• Principal Investigator: KANNO Motohiro Division of Eng., Graduate School, Professor, 大学院・工学系研究科, 教授 (60011128)
• Co-Investigator(Kenkyū-buntansha): KITAOKA Satoshi Japan Fine Ceramics Center, Researcher, 試験研究所, 研究員 ; MATSUBARA Hideaki Japan Fine Ceramics Center, Manager, 試験研究所, 主管主席研究員 ; ITOH Goroh Nagaoka Univ. of Tech., Dept. of Mech Eng., Associate Professor, 工学部, 助教授 (80158758)
• Project Period (FY): 1995 – 1996
• Keywords: ceramic / gas / ultra-high vacuum / mass spectrometer / 質量分析計

Research Abstract

An equipment has been developed for detecting trace amounts of gases evolved from ceramic materials during fracture in order to investigate gases trapped in the sintered body of ceramic materials. It consists of a tensile-compression testing machine, a quadrupole mass spectrometer, a main chamber and a subchamber. The main chamber is evacuated with a tandem turbo molecular pump and a non evaporable getter pump. After baking the main chamber at 453K for 86.4ks and cooling it down to ambient temperature, the total pressure of the chamber falls to about 1*10^<-8>Pa. A multiple sample holder is also developed which enables us to fracture up to 7 samples sequentially. This holder can be transported magnetically into the main chamber without exposing the inside of the chambers to air. In addition, the subchamber is equipped with an apparatus to heat samples as well as the holder up to 773K in ultra-high vacuum for removing gases absorbed on the samples and the holder before transporting.
The analyzes of gases evolved from three structural ceramics, i. e., Al_2O_3, Si_3N_4 and SiC,during four-point bending tests have been performed in the ultra-high vacuum chamber using a quadrupole mass spectrometer in a rapid scan mode. The gases H_2, CH_4, N_2, AR,etc. were evolved at the moment of fracture from all specimens. The main gases trapped in the sintered body of Al_2O_3, Si_3N_4 and SiC are N_2, H_2 and Ar, respectively.