Title:
【発明の名称】強度評価方法
Document Type and Number:
Japanese Patent JP2765288
Kind Code:
B2
Abstract:
PURPOSE:To evaluate the strength of ceramic structure quantitatively by applying a stress intensity factor to a right angle groove part and determining critical fracture values of stress intensity factor for three deformation modes at the groove part. CONSTITUTION:A sharp right angle groove part of ceramic structure is recognized as a crack having open angle of 90 deg. and four point bending test is performed to determine the relationship between the radius of curvature at groove part and fracture load. Experimental values 2 do not match with fracture load 3 predicted through finite element analysis and the radius of curvature of several tens mum corresponds to crack having open angle of 0 deg.. When a sharp right angle groove is treated as a chappy crack, extended stress intensity factors K' corresponding to three modes, opening, shift, and tear are determined as follows; K'1=sigmay(2pir)<0.45>, K'2=tauxy(2pir)<0.09>, K'3=tau(2pir)<0.33>, where sigma: stress, tau: shearing stress, r: distance from the tip of groove. The extended stress intensity factors K' thus determined represent critical fracture values inherent to the structure and thereby the strength can be quantified.
Inventors:
Ishibashi Masahiro
Atsushi Fujimoto
Atsushi Fujimoto
Application Number:
JP20324491A
Publication Date:
June 11, 1998
Filing Date:
July 19, 1991
Export Citation:
Assignee:
NEC
International Classes:
G01N3/00; G01L1/00; G06F17/50; H01L21/66; G01N33/38; (IPC1-7): G01L1/00; G01N3/00
Attorney, Agent or Firm:
Sugano Naka