Femtosecond laser pulse surface structuring methods and materials resulting therefrom

Patent metadata

Field	Value
Publication number	US-2017100797-A1
Application number	US-201615384398-A
Country	US
Kind code	A1
Filing date	Dec 20, 2016
Priority date	Sep 29, 2006
Publication date	Apr 13, 2017
Grant date	—

Abstract

Embodiments of the present invention are generally directed to materials processing methods using femtosecond duration laser pulses, and to the altered materials obtained by such methods. The resulting nanostructured (with or without macro- and micro-structuring) materials have a variety of applications, including, for example, aesthetic applications for jewelry or ornamentation; biomedical applications related to biocompatibility; catalysis applications; and modification of, for example, the optical and hydrophilic properties of materials including selective coloring.

First claim

1 - 20 . (canceled)

21 . An object comprising:
a metal or metal alloy having a surface with a femtosecond laser treated region; the surface having a pre-laser treatment profile defining an inward orientation facing into the object and an outward orientation facing away from the object; the metal or metal alloy having a first light absorption when profiled per the pre-laser treatment profile; the femtosecond laser treated region of the surface comprising a plurality of nanoscale structure shapes formed on the metal or metal alloy, the nanoscale structure shapes including: a plurality of nanoscale cavities extending inwardly into the pre-laser treatment profile; and a plurality of nanoscale protrusions extending outwardly away from the pre-laser treatment profile; the nanoscale structure shapes increasing absorption of at least some light wavelengths of the metal or metal alloy within the femtosecond laser treated region so that the metal or metal alloy within the femtosecond laser treated region has a second light absorption greater than the first light absorption; and wherein the femtosecond laser treated region does not include microscale cavities or microscale protrusions.

22 . The object of claim 21 , wherein at least some of the nanoscale protrusions are each adjacent one of the nanoscale cavities.

23 . The object of claim 22 , further comprising a plurality of nanoscale rims, wherein at least some of the nanoscale rims are each around one of the nanoscale cavities, and wherein at least some of the nanoscale protrusions include nanoscale spherical structures.

24 . The object of claim 21 , wherein at least some of the nanoscale cavities are nanoscale pores having a diameter in the range of 40-100 nm.

25 . The object of claim 21 , wherein at least some of the nanoscale protrusions have a diameter in the range of 20-70 nm and a length of 20-80 nm.

26 . The object of claim 21 , wherein the nanoscale structure shapes are configured to increase the metal or metal alloy's absorption of substantially all visible light wavelengths to give the metal or metal alloy a black or grey appearance.

27 . The object of claim 21 , wherein the nanoscale structure shapes are configured to increase the metal or metal alloy's absorption of some visible light wavelengths to give the metal or metal alloy a colored appearance.

28 . The object of claim 27 , wherein the colored appearance is the same at different viewing angles.

29 . The object of claim 21 , wherein the nanoscale structure shapes are configured to increase the metal or metal alloy's absorption of some infrared electromagnetic wavelengths.

30 . The object of claim 21 , wherein the nanoscale structure shapes are configured to increase the metal or metal alloy's absorption of some ultraviolet electromagnetic wavelengths.

31 . The object of claim 21 , wherein the nanoscale structure protrusions are not formed by post-ablation redeposition.

32 . The object of claim 21 , wherein the plurality of nanoscale protrusions comprise spherical nanoparticles.

33 . An object comprising:
a metal or metal alloy having a surface with a femtosecond laser treated region; the surface having a pre-laser treatment profile; the metal or metal alloy having a first light absorption when profiled per the pre-laser treatment profile; the femtosecond laser treated region of the surface comprising laser-induced periodic surface structures comprising:
periodic microscale structure shapes formed on the metal or metal alloy; and
a plurality of nanoscale structure shapes formed by the metal or metal alloy covering the periodic microscale structure shapes, the nanoscale structure shapes including a plurality of nanoscale protrusions extending outwardly away from the microscale structure shapes;
the laser-induced periodic surface structures increasing absorption of at least some light wavelengths of the metal or metal alloy within the femtosecond laser treated region so that the metal or metal alloy within the femtosecond laser treated region has a second light absorption greater than the first light absorption.

34 . The object of claim 33 , wherein the microscale structure shapes comprise a plurality of at least one of micropores, microgrooves, and microchannels.

35 . The object of claim 33 , wherein the laser-induced periodic surface structures have a period that is less than a wavelength of the femtosecond laser.

36 . The object of claim 33 , wherein the laser-induced periodic surface structures form a grating.

37 . The object of claim 33 , wherein the laser-induced periodic surface structures have a period on a sub-micron level.

38 . The object of claim 33 , wherein the laser-induced periodic surface structures have a microroughness in a range of 1-15 micrometers.

39 . The object of claim 33 , wherein the laser-induced periodic surface structures reflect less than 10% of light having a wavelength between 250-2500 nm.

40 . The object of claim 33 , wherein the laser-induced periodic surface structures exhibit different colors depending on viewing angle due to a grating effect.

Assignees

• Univ Rochester

Inventors

• Guo Chunlei
• Vorobyev Anatoliy Y

Classifications

• Y10T428/12201

  Width or thickness variation or marginal cuts repeating longitudinally · CPC title

• B23K2103/14

  Titanium or alloys thereof · CPC title

• B23K2103/42

  Plastics other than composite materials · CPC title

• B23K26/355 Primary

  Texturing · CPC title

• C21D1/09

  by direct application of electrical or wave energy; by particle radiation · CPC title