Method and apparatus for measuring internal mechanical stress of

Details Method and apparatus for measuring internal mechanical stress of Method and apparatus for measuring internal mechanical stress of

1989-12-04

1991-09-10

Snow, Walter E.

Electricity: measuring and testing

Magnetic

Stress in material measurement

73779, G01B 724, G01R 3318

Patent

active

050477170

ABSTRACT:
A method and apparatus for measuring the mechanical internal stress of a body of ferromagnetic material includes generating a sinusoidal magnetic field at given site of a ferromagnetic body. First and second amplitudes of the third harmonic component of the induction at first and second measuring sites at the body being mutually spaced apart by an angle of 90.degree. with respect to the given site, are measured. An associated first curve from a first predetermined family of curves representing the third harmonic component of the induction as a function of the mechanical stress for the first amplitude, is located. An associatead second curve from a second predetermined family of curves representing the third harmonic component of the induction as a function of the mechanical stress for the second amplitude, is located. Especially the first family of curves is associated with a first predetermined measuring direction or a direction parallel thereto and the second family of curves is associated with a second measuring direction perpendicular to the first predetermined measuring direction. A point of intersection of the first and the second curves is determined. A given direction is defined by a connecting line passing through the given site of the sinusoidal magnetic field and through the first measuring site. The abscissa value of the point of intersection beginning at a predetermined abscissa value is determined as a measured value for the magnitude of the mechanical internal stress in the given direction.

REFERENCES:
patent: 3535625 (1970-10-01), Pratt
patent: 3636437 (1977-01-01), Souland Jr. et al.
patent: 3798537 (1974-03-01), Dahm
U.S. Publication "Reviews of Modern Physics" vol. 21, No. 4, Oct. 1949, article Physical Theory of Ferromagnetic Domains by Kittel, pp. 541-583.

Affiliated with

Also associated with

Rating

Method and apparatus for measuring internal mechanical stress of does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method and apparatus for measuring internal mechanical stress of, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for measuring internal mechanical stress of will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-542610