Autoradiography-Based Differential Wear Mapping

• US 20080019582A1
• Filed: 07/20/2007
• Published: 01/24/2008
• Est. Priority Date: 07/21/2006
• Status: Active Grant

• Current Assignee: Southwest Research Institute
• Original Assignee: Southwest Research Institute
• Inventors: Eberle, Douglas C., Treuhaft, Martin B., Wall, Craig M.
• Granted Patent: US 8,050,489 B2
• Time in Patent Office: Days
• US Class Current: 382/132
• CPC Class Codes: G01N 23/04 and forming images of the material

Abstract

Methods and systems for the differential wear mapping of the surface of an object are described. The process involves establishing a radioactive wearing surface on the object through surface layer activation (SLA) and/or radioactive ion implantation (RII) and imaging the wearing surface with conformal photographic or x-ray film to produce a first autoradiograph providing a baseline profile of the wearing surface. After subjecting the object to wear during testing the wearing surface is again imaged with conformal photographic or x-ray film to produce a second autoradiograph providing a worn profile. The first and second autoradiographs of the wearing surface are digitized and compared to produce a differential wear map of the surface of the object.

Claims

1. A system for differential wear mapping of the surface of an object, the system comprising:

(a) a device for establishing a radioactive wearing surface on the object;

(b) a first conformal radiation imaging device for producing a first autoradiograph providing a baseline profile of the wearing surface;

(c) a second conformal radiation imaging device for producing a second autoradiograph providing a worn profile of the wearing surface;

(d) a digitizer for establishing first and second data sets representing the first and second autoradiographs; and

(e) a data processor for comparing the first and second data sets and establishing a differential data set, the differential data set characterizing a differential wear map of the surface of the object.

2. The system of claim 1 wherein the device for establishing a radioactive wearing surface comprises a device for surface layer activation (SLA) of the surface layers of the object.

3. The system of claim 1 wherein the device for establishing a radioactive wearing surface comprises a device for radioactive ion implantation (RII) in the surface layers of the object.

4. The system of claim 1 wherein the first and second conformal radiation imaging devices each comprise a sheet of flexible photographic imaging film.

5. The system of claim 1 wherein the first and second conformal radiation imaging devices each comprise a sheet of flexible x-ray imaging film.

6. The system of claim 1 wherein the first and second conformal radiation imaging devices each comprise a conformable two-dimensional solid state detector array.

7. The system of claim 4 wherein the digitizer comprises an image scanner for creating digital image data of the sheet of flexible photographic imaging film.

8. The system of claim 5 wherein the digitizer comprises an image scanner for creating digital image data of the sheet of flexible x-ray imaging film.

9. The system of claim 6 wherein the digitizer comprises a digital image processor for creating digital image data from the output of the solid state detector array.

10. The system of claim 1 further comprising an indexing device for consistent positioning and repositioning of the first and second conformal radiation imaging devices on the wearing surface of the object.

11. A system for differential wear mapping of the surface of an object, the system comprising:

(a) a surface layer activation/implantation device for establishing a radioactive wearing surface on the object;

(b) a first sheet of flexible radiation imaging film conformable to the surface of the object for producing a first autoradiograph providing a baseline profile of the wearing surface;

(c) a second sheet of flexible radiation imaging film conformable to the surface of the object for producing a second autoradiograph providing a worn profile of the wearing surface;

(d) an indexing device for consistent positioning and repositioning of the first and second sheets of flexible radiation imaging film on the wearing surface of the object;

(e) a digital scanner for establishing first and second digital data sets representing the first and second autoradiographs; and

(f) a data processor for comparing the first and second data sets and establishing a differential data set, the differential data set characterizing a differential wear map of the surface of the object.

12. A method for differential wear mapping of the surface of an object, the method comprising the steps of:

(a) establishing a radioactive wearing surface on the object;

(b) imaging the wearing surface to produce a first autoradiograph providing a baseline profile of the wearing surface;

(c) subjecting the object to wear during testing;

(d) imaging the wearing surface to produce a second autoradiograph providing a worn profile of the wearing surface;

(e) digitizing the first and second autoradiographs of the wearing surface; and

(f) comparing the digitized first and second autoradiograph to produce a differential wear map of the surface of the object.

13. The method of claim 12 wherein the step of establishing a radioactive wearing surface on the object comprises carrying out a surface layer activation (SLA) process on the surface layers of the object.

14. The method of claim 12 wherein the step of establishing a radioactive wearing surface on the object comprises carrying out a radioactive ion implantation (RII) process in the surface layers of the object.

15. The method of claim 12 wherein each of the steps of imaging the wearing surface comprise positioning, conforming, and exposing a sheet of flexible photographic imaging film to the wearing surface of the object.

16. The method of claim 12 wherein each of the steps of imaging the wearing surface comprise positioning, conforming, and exposing a sheet of flexible x-ray imaging film to the wearing surface of the object.

17. The method of claim 12 wherein each of the steps of imaging the wearing surface comprise positioning, conforming, and exposing a two-dimensional solid state detector array to the wearing surface of the object.

18. The method of claim 12 further comprising the step of indexing a position of the first autoradiograph so as to allow repetition of the step of imaging the wearing surface.

19. The method of claim 12 further comprising the step of compensating for any non-linear response characteristics in the wearing surface imaging steps, for any non-wear induced reductions in radiation, and for any non-homogeneity in the imaging medium.

20. A method for differential wear mapping of the surface of an object, the method comprising the steps of:

(a) establishing a radioactive wearing surface on the object through surface layer activation (SLA) or radioactive ion implantation (RII);

(b) imaging the wearing surface with conformal photographic/x-ray film to produce a first autoradiograph providing a baseline profile of the wearing surface;

(c) indexing a position of the first autoradiograph so as to allow repetition of the step imaging the wearing surface;

(d) subjecting the object to wear during testing;

(e) imaging the wearing surface with conformal photographic/x-ray film to produce a second autoradiograph providing a worn profile of the wearing surface;

(f) digitizing the first and second autoradiographs of the wearing surface;

(g) compensating for any non-linear response characteristics of the photographic/x-ray film, for any non-wear induced reductions in radiation, and for any non-homogeneity in the photographic/x-ray film; and

(h) comparing the digitized first and second autoradiograph to produce a differential wear map of the surface of the object.