Hitachi, Ltd.

Hitachi Naka Electronics Co., Ltd.

Yoshio Fukuda

Kunio Enomoto

Sho Kusumoto

Toshio Ishizuki

Tsutomu Masumoto

Sadao Nemoto

Ken-ichi Honda

Naoki Sakurama

The present invention is an electric capacitance strain gauge provided with a pair of installing frames connected to each other, electrical insulating members with a stepped shape fixed onto the said pair of installing frames by insertion and two pairs of electrode plates with a stepped shape fixed onto the said electrical insulating members by insertion. As the electrical insulating members and the installing frames are positioned at a stepped part of the stepped shape when the electrical insulating members are fixed on the installing frames by insertion, and positioning of the electrode plates and the electrical insulating members is carried out at a stepped part of the electrode plates when the electrode plates are installed on the electrical insulating members by insertion, the relative positions of each member can be accurately determined. As the relative positions of each member of the electric capacitance strain gauge is accurately determined, the possibility that characteristics of the electric capacitance strain gauge are affected by each electric capacitance strain gauge is reduced.

Electric capacitance strain gauge

AE signals due to a crack developed in a metal test object are detected by a number of AE sensors mounted on the metal test object. Based on time differences between the signals from the respective AE sensors, crack source points are determined. Then, based on the crack source points, a crack source plane is determined. The crack source plane is divided into a number of areas and a point of maximum number of crack source points in each of the areas is determined. Based on the points of maximum number of crack source points in the respective areas, a shape of the crack in the test object is determined.

Method for determining shape of crack

There is provided polychromatic X-ray source used in a polychromatic X-ray diffraction apparatus, in which polychromatic X-rays are cast upon a sample to be analyzed, the energies of the X-rays diffracted from the crystallographic planes of the sample are measured and the physical properties of the sample are detected on the basis of the measured energies. The polychromatic X-ray source has a container made of radiation shielding material and having an X-ray outlet channel and the container contains therein a radionuclide for emitting radioactive rays and a substance for scattering and absorbing the radioactive rays emitted from the substance so as to obtain polychromatic X-rays. The polychromatic X-rays emitted from the substance travel through the X-ray outlet channel and are then made parallel through a Soller slit to be cast upon the sample. A slide door is provided in the channel so as to block the polychromatic X-rays if necessary.

Polychromatic X-ray source for diffraction apparatus using

Growing community of inventors

Hitachi, Japan

Yoshio Fukuda