Method and apparatus for evaluating metal cleanliness

Claim 2

A non-destructive testing method suitable for determining the location and character of discontinuities and flaws in a sample of otherwise substantially homogeneous material comprising the steps of: bombarding the sample with a beam of sonic wave energy comprising successive pulses of sonic wave energy and causing said beam to scan back and forth from edge to edge along one transverse dimension of the sample while causing the beam to advance through an increment at essentially right angles to said one transverse dimension after each scan, detecting pulses of sonic wave energy reflected from said sample as the beam scans back and forth, discriminating against a portion of the total reflected energy by blocking out energy reflected from those opposite surfaces of the sample extending transverse to the scanning beam, and causing a recording means to move over a recording surface along one dimension while deflecting said recording means at right angles to said one dimension as a function of the amplitude of said reflected energy, the recording means continually moving along said one dimension without reversing during a plurality of successive back and forth scans of the beam of sonic wave energy, whereby the location of flaws in said sample represented by points of increased amplitude recorded on said recording surface can be determined from a consideration of the location of said points of increased amplitude along said one dimension.

Claim 3

The meThod of claim 1 wherein said recording means moves over said recording surface at a speed less than the scanning speed of said beam of sonic wave energy.

Claim 4

The method of claim 1 wherein said recording means comprises an electron beam and said recording surface comprises the screen of a storage oscilloscope.

Claim 5

Apparatus for non-destructive testing suitable for determining the location and character of discontinuities in addition to flaws in a sample of otherwise homogeneous material, comprising means for bombarding said sample with a beam of sonic wave energy comprising successive pulses of sonic wave energy, means for deflecting said beam to cause it to scan back and forth from edge to edge along one transverse dimension of the sample while causing the beam to advance through an increment at essentially right angles to said one transverse dimension after each scan, means for detecting pulses of sonic wave energy reflected from said sample as the beam scans back and forth, means coupled to said detecting means for discriminating against a portion of the total reflected wave energy by blocking out energy reflected from those opposite surfaces of the sample extending transverse to the scanning beam, a storage oscilloscope, and means coupling said discriminating means to said storage oscilloscope to cause the electron beam thereof to be deflected in one direction as a function of the amplitude of said reflected energy while causing said beam to move continuously and without reversing along a dimension at right angles thereto during a plurality of successive back and forth scans of the beam of sonic wave energy, whereby the location of flaws in said sample represented by points of increased amplitude in the trace recorded on the screen of said storage oscilloscope can be determined from a consideration of the location of said points of increased amplitude along said other dimension.

Claim 6

Apparatus for non-destructive testing suitable for determining the location and character of discontinuities in addition to flaws in a sample of otherwise homogeneous material, comprising means for bombarding said sample with a beam of sonic wave energy comprising successive pulses of sonic wave energy, means for deflecting said beam to cause it to scan back and forth from edge to edge along one transverse dimension of the sample while causing the beam to advance through an increment at essentially right angles to said one transverse dimension after each scan, means for detecting pulses of sonic wave energy reflected from said sample as the beam scans back and forth, means coupled to said detecting means for discriminating against a portion of the total reflected wave energy by blocking out energy reflected from those opposite surfaces of the sample extending transverse to the scanning beam, a storage oscilloscope, and means coupling said discriminating means to said storage oscilloscope to cause the electron beam thereof to be deflected in one direction as a function of the amplitude of said reflected energy while causing said beam to move continuously and without reversing along a dimension at right angles thereto during a plurality of successive back and forth scans of the beam of sonic wave energy, whereby the location of flaws in said sample represented by points of increased amplitude in the trace recorded on the screen of said storage oscilloscope can be determined from a consideration of the location of said points of increased amplitude along said other dimension.