Process and device for determining the quality of a weld seam or a thermal spray coating and application

• US 20060279731A1
• Filed: 06/13/2006
• Published: 12/14/2006
• Est. Priority Date: 06/13/2005
• Status: Abandoned Application

• Current Assignee: Fraunhofer-Gesellschaft, Daimler Chrysler Company LLC (Stellantis NV)
• Original Assignee: Fraunhofer-Gesellschaft, Daimler Chrysler Company LLC (Stellantis NV)
• Inventors: Hoschele, Jorg, Beyer, Eckhard, Steinwandel, Jurgen, Ohnesorge, Alexander, Nowotny, Steffen
• Application Number:
  US11/451,690
• Publication Number:
  US 20060279731A1
• Time in Patent Office: Days
• US Class Current: 356/318
• CPC Class Codes: G01J 3/1809 Echelle gratings
• CPC Class Codes: G01J 3/443 Emission spectrometry
• CPC Class Codes: G01J 3/457 Correlation spectrometry, e.g. of the intensity G01J3/453 takes precedence
• CPC Class Codes: G01N 21/718 Laser microanalysis, i.e. with formation of sample plasma

Abstract

In material depositing processes such as welding or thermal spraying the large variety of processes and material parameters necessitate a broad range of the resulting characteristics of the applied material. The task of the present invention is comprised of providing a process and a device for determining the quality of specific layer characteristics, in particular their adhesion or strength of joining to the base material. This task is solved thereby, that as the quality characteristic there is employed the degree of mixing of the applied material with the base material.

Claims

1. Process for determining the quality of a weld seam or a thermal spray coated layer, wherein the degree of mixing of the applied material with the base is employed as the quality characteristic, the process comprising:

inducing surface plasma by an energy impulse,

determining the degree of mixing by spectral analysis of the radiation emitted by surface plasma induced by an energy impulse using a spectrometer, wherein the spectral analysis is adjusted to occur subsequent to the energy impulse,

wherein a LIPS sensor head (laser induced plasma spectroscopy) is employed, which is connected with the processing head.

2. A process according to claim 1, wherein the spectral analysis occurs by means of an Echelle-spectroscopy or by means of two-wavelength spectroscopy by means of an interference filter, preferably with subsequent amplifier unit, in particular a photo multiplier.

3. A process according to claim 1, wherein the spectral analysis of at least two spectral regions of the radiation admitted by the location to be examined occurs.

4. A process according to claim 1, wherein the spectral analysis is time delayed to follow the energy impulse by 50 to 300 ns, in particular 80-150 ns.

5. Process according to claim 1, wherein, depending upon the base material and the applied material, specific spectral regions are selected, which are preferably maintained in a computer data bank, and provided for analysis.

6. A device for determining the quality of a weld seam or a thermal spray coated layer for carrying out a process for determining the quality of a weld seam or a thermal spray coated layer, wherein the degree of mixing of the applied material with the base is employed as the quality characteristic, the process comprising:

(a) inducing surface plasma by an energy impulse, (b) determining the degree of mixing by spectral analysis of the radiation emitted by surface plasma induced by an energy impulse using a spectrometer, wherein the spectral analysis is adjusted to occur subsequent to the energy impulse, wherein a LIPS sensor head (laser induced plasma spectroscopy) is employed, which is connected with the processing head, comprising

a spectrometer,

a computer connected thereto, in which is stored;

a first correlation between spectral parameters and the degree of mixing of the material applied by the processing head with the base material, and

a second correlation between the degree of mixing and a quality skill,

a device for producing a surface plasma, and

a device for adjusting a time delay between the production of the surface plasma and the spectral analysis by means of the spectrometer, wherein the device for production of a surface plasma includes a LIPS sensor head, which is connected with the processing head.

7. A device according to claim 6, thereby characterized, that the device for production of a surface plasma includes a short pulse laser.

8. A process for manufacture of a vehicle, preferably in the production of automotive or aviation vehicles or their components, wherein the quality of a weld seam or a thermal spray coated layer is determined, and wherein the degree of mixing of the applied material with the base is employed as the quality characteristic, the process comprising:

inducing surface plasma by an energy impulse,

determining the degree of mixing by spectral analysis of the radiation emitted by surface plasma induced by an energy impulse using a spectrometer, wherein the spectral analysis is adjusted to occur subsequent to the energy impulse,

wherein a LIPS sensor head (laser induced plasma spectroscopy) is employed, which is connected with the processing head.