Method for smoothing and polishing surfaces by treating them with energetic radiation

• US 20060081573A1
• Filed: 06/24/2003
• Published: 04/20/2006
• Est. Priority Date: 06/27/2002
• Status: Active Grant

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: Pirch, Norbert, Wissenbach, Konrad, Willenborg, Edgar
• Granted Patent: US 7,592,563 B2
• Time in Patent Office: Days
• US Class Current: 219/121.660
• CPC Class Codes: B23K 26/3576 Diminishing rugosity, e.g. grinding; Polishing; Smoothing
• CPC Class Codes: B24B 1/00 Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
• CPC Class Codes: C21D 1/09 by direct application of electrical or wave energy; by particle radiation

Abstract

The present invention relates to a method for smoothing and polishing surfaces by treating them with energetic radiation, in particular laser radiation, in which the to-be-smoothed surface (1) is remelted in a first treatment step using said energetic radiation (3) and employing first treatment parameters at least once down to a first remelting depth (10) of approx. 5 to 100 μm, which is greater than a structural depth of the to-be-smoothed structures of said to-be-smoothed surface (1), wherein continuous radiation or pulsed radiation (3) with a pulse duration of ≧100 μs is employed. The method makes it possible to automatically polisch any three-dimensional surface fast and cost effective.

Claims

1. A method for smoothing and polishing surfaces by treating them with energetic radiation (3), in particular laser radiation, in which the to-be-smoothed surface (1) is remelted in a first treatment step using said energetic radiation (3) and employing first treatment parameters at least once down to a first remelting depth (10), which is greater than a structural depth of the to-be-smoothed structures of said to-be-smoothed surface and is ≦

100 μ

m, wherein

in said first treatment step continuous energetic radiation or pulsed energetic radiation with a pulse duration of ≧

100 μ

s is employed and said surface (1) is remelted down to a first remelting depth (10) of 5 to 100 μ

m.

2. A method according to claim 1, wherein in a second treatment step using said energetic radiation (3) and employing second treatment parameters, micro-roughness remaining on said surface (1) after said first treatment step is leveled by remelting down to a second remelting depth (14), which is less than said first remelting depth (10), and by evaporating roughness peaks (15).

3. A method according to claim 1, wherein said first treatment parameters are selected in such a manner that no ablation of material occurs.

4. A method according to claim 2, wherein pulsed laser radiation with a pulse duration of ≦

1 μ

s is employed in said second treatment step.

5. A method according to claim 1, wherein said surface (1) is remelted in said first treatment step down to a first remelting depth (10) of approximately 10 to 80 μ

m.

6. A method according to claim 2, wherein said surface (1) is remelted in said second treatment step down to a second remelting depth (14) of maximally 5 μ

m.

7. A method according to claim 1, wherein said surface (1) is remelted in said first treatment step multiple times in succession.

8. A method according to claim 7, wherein with each new remelting step, said first remelting depth is selected less deep than in the previous remelting step.

9. A method according to claim 7, wherein said energetic radiation (3) is led in parallel paths (6) over said surface (1) with successive remelting steps of a section (4) of said surface (1) being carried out with paths (6) turned at an angle.

10. A method according to claim 1, wherein treatment in said first treatment step occurs successively in a multiplicity of adjacent sections (4) of said surface (1), with the treatment parameters being changed continuously or in steps towards the border of said sections (4) in such a manner that said first remelting depth (10) decreases to said border of said sections (4).

11. A method according to claim 1, wherein in order to retain edges (13) on said surface (1), said first treatment parameters of said first treatment step are changed continuously or in steps in such a manner that said first remelting depth (10) decreases toward said edges (13).

12. A method according to claim 1, wherein said laser radiation (3) is led on one or a multiplicity of meandering paths (6) over said surface (1).

13. A method according to claim 2, wherein said surface (1) is impinged with protective gas during said first and said second treatment step.

14. A method according to claim 1, wherein treatment occurs with a beam cross section in form of a line or with a rectangular beam cross section of said energetic radiation (3).

15. A method according to claim 1, wherein said to-be-smoothed surface (1) is preheated before remelting.

16. A method according to claim 1, wherein said first treatment parameters are selected in such a manner that structures of significance of said to-be-smoothed surface (1) are retained during remelting.