In situ monitoring of reactive material using ultrasound

1. A method of non-destructively monitoring reactive material through a substrate for changes in material properties that designate the condition of the reactive material during cure and service life, said method comprising the steps of:

(a) prescribing a certain amount of thickness for the substrate;

(b) placing a transducer on a portion of the substrate generally parallel to at least one interface of the substrate and the reactive material, said interface being located in a surface of the substrate in contact with the reactive material;

(c) generating ultrasonic waves with the transducer that travel through the substrate and are reflected on encountering an interface; and

(d) detecting and determining whether the reflected sound waves indicate changes in material properties of the reactive material.

2. The method of claim 1 wherein said reactive material includes adhesives, coatings, sealants and combinations thereof.

3. The method of claim 1 wherein said material properties include modulus, density, thickness, geometry and combinations thereof.

4. The method of claim 1 wherein said ultrasonic waves generated are perpendicular to the interfaces.

5. The method of claim 1 further comprising receiving the ultrasonic waves reflected upon encountering an interface and determining whether the reflected sound waves indicate changes in material properties of the reactive material with a computer that analyzes at least one of the intensity, frequency distribution, or time between reflections of the reflected sound waves.

6. The method claim 1 further comprising detecting flaws in reactive materials through said substrate.

7. The method of claim 6 wherein said flaws include cracks, inclusions, corrosions, non-uniformities, inhomogeneities and combinations thereof.

8. The method of claim 1 , wherein the material properties include the cure state of the reactive material.

9. The method of claim 1 , wherein the reactive material is concealed behind the substrate.

10. The method of claim 1 , further comprising predicting when repairs or replacements of reactive materials should be performed.

11. The method of claim 1 , further comprising detecting the physical failure of reactive materials.

12. An assembly for non-destructively monitoring reactive material through a substrate with at least one interface, comprising:

(a) a transducer placed on a portion of the substrate wherein the face of the transducer is parallel to at least one interface of the substrate and the reactive material, said interface being located in a surface of the substrate in contact with the reactive material;

(b) generating ultrasonic waves with the transducer that travel through the substrate and are reflected on encountering an interface; and

(c) detecting and determining whether the reflected sound waves indicate changes in material properties of the reactive material.

13. The assembly of claim 12 wherein the computer displays the intensity, frequency distribution, and time between reflections at each interface.

14. The assembly of claim 12 wherein the computer quantifies and analyzes at least one of the intensity, frequency distribution, or time between reflections at each interface to determine a degree of change in material properties of the reactive material.

15. The assembly of claim 12 , further comprising stored data in the computer, including a prescribed thickness of the substrate and reactive material.

16. The assembly of claim 12 , further comprising stored data in the computer, including known changes in intensity, frequency distribution, and time between reflections due to flaws or the cure state in the reactive material.

17. A system for non-destructively monitoring a reactive material on a substrate comprising:

(a) a first transducer placed on a portion of the substrate wherein the face of the transducer is parallel to an interface of the substrate and the reactive material, said interface being located in a surface of the substrate in contact with the reactive material;

(b) a second transducer positioned next to the first transducer, wherein said second transducer is aligned so that the sound waves reflected upon the interaction of angular incident waves generated by the first transducer upon encountering an interface are detected by the second transducer;

(c) detecting and determining whether the reflected sound waves indicate changes in material properties of the reactive material.

18. The system of claim 17 wherein the computer displays the intensity, frequency distribution, and time between reflections at each interface.

19. The system of claim 17 wherein the computer quantifies and analyzes at least one of the intensity, frequency distribution, or time between reflections at each interface to determine a degree of change in material properties of the reactive material.

20. A system for non-destructively monitoring a reactive material on a substrate with a front and back surface, comprising:

(a) a first transducer placed on the front surface of the substrate wherein the face of the transducer is parallel to an interface of the substrate to the reactive material, said interface being located in a surface of the substrate in contact with the reactive material;

(b) a second transducer positioned on the back surface of the substrate, aligned to detect sound waves transmitted by the first transducer upon encountering said interface; and

(c) detecting and determining whether the reflected sound waves indicate changes in material properties of the reactive material.

21. The system of claim 20 further comprising a prescribed thickness of the substrate and the reactive material.