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

• US 7,592,563 B2
• Filed: 06/24/2003
• Issued: 09/22/2009
• Est. Priority Date: 06/27/2002
• Status: Expired due to Fees

• 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
• Primary Examiner(s): Heinrich; Samuel M
• Application Number:
  US10/519,146
• Publication Number:
  US 20060081573A1
• Time in Patent Office: 2,282 Days
• Field of Search: 219/121.65, 219/121.66, 219/121.61, 219/121.16, 219/121.17, 219/121.2, 219/121.35, 219/121.69, 219/121.76, 219/121.85, 148/512
• US Class Current: 219/121.17
• 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 is remelted in a first treatment step using said energetic radiation and employing first treatment parameters at least once down to a first remelting depth 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, wherein continuous radiation or pulsed radiation with a pulse duration of ≧100 μs is employed. The method makes it possible to automatically polish any three-dimensional surface fast and cost effective.

Claims

1. A method for smoothing and polishing a to-be-smoothed surface, comprising:

a first treatment step comprising remelting the to-be-smoothed surface using energetic radiation while employing first treatment parameters at least once down to a first remelting depth which is greater than a structural depth of to-be-smoothed structures of said to-be-smoothed surface, wherein the using of energetic radiation includes using continuous energetic radiation or pulsed energetic radiation with a pulse duration of ≧

100 μ

s, such that said surface is remelted down to a first remelting depth of about 5 to 100 μ

m, and

a second treatment step comprising leveling micro-roughness remaining on said surface after said first treatment step by remelting the micro-roughness using said energetic radiation while employing second treatment parameters down to a second remelting depth, and by evaporating roughness peaks, wherein the second remelting depth is less than said first remelting depth.

2. A method according to claim 1, including selecting said first treatment parameters so that no ablation of material occurs.

3. A method according to claim 1, wherein the using step includes using pulsed laser radiation with a pulse duration of ≦

1 μ

s is employed in said second treatment step.

4. A method according to claim 1, wherein the remelting step includes remelting said surface in said first treatment step down to a first remelting depth of approximately 10 to 80 μ

m.

5. A method according to claim 1, wherein the remelting of said surface in said second treatment step includes remelting said surface down to a second remelting depth of maximally 5 μ

m.

6. A method according to claim 1, wherein the remelting step includes remelting said surface in said first treatment step multiple times in succession.

7. A method according to claim 6, wherein with each new remelting step, selecting said first remelting depth less deep than in the previous remelting step.

8. A method according to claim 6, wherein the remelting step includes leading said energetic radiation in parallel paths over said surface with successive remelting steps of a section of said surface being carried out with paths turned at an angle.

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

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

11. A method according to claim 1, wherein the remelting step includes leading said energetic radiation on one or a multiplicity of meandering paths over said surface.

12. A method according to claim 1, including impinging said surface with protective gas during said first and said second treatment steps.

13. 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.

14. A method according to claim 1, further comprising preheating said to-be-smoothed surface before remelting.

15. A method according to claim 1, including selecting said first treatment parameters so that structures of significance of said to-be-smoothed surface are retained during remelting.