Laser surface treatment on stainless steel and nickel alloys for adhesive bonding

Patent metadata

Field	Value
Publication number	US-2020316721-A1
Application number	US-202016839753-A
Country	US
Kind code	A1
Filing date	Apr 3, 2020
Priority date	Apr 5, 2019
Publication date	Oct 8, 2020
Grant date	—

Abstract

Methods and systems for the laser surface treatment on stainless steel alloys and nickel alloys may include a computer may be programmed to set a laser path corresponding to a predetermined geometric pattern. A laser may be coupled to the computer and apply a pulsed laser beam to a contact surface of the substrate along the predefined geometric pattern. The pulsed laser beam may have a laser power between 0.1 W and 100 W, single pulse fluence 1 mJ/mm2 and 1025 mJ/mm2 and a laser speed between 25.4 cm/s and 127 cm/s. The laser may generate an open pore oxide layer on the contact surface of the substrate with a thickness of 0.1-1 μm, an open pore distance of 0.05-1 μm. The open pore oxide layer may have a topography corresponding to the predefined geometric pattern. The topography may contain open pore structures and promote adhesive bond performance.

First claim

What is claimed is:

1 . A method for surface treating a substrate prior to adhesive bonding, the method comprising:
determining, by a processor, a predetermined set laser path corresponding to a predefined geometric pattern; commanding, by the processor, a laser to apply a pulsed laser beam to a contact surface of the substrate along the predefined geometric pattern, the pulsed laser beam having a single pulse fluence between 1 mJ/mm 2 and 1025 mJ/mm 2 .

2 . The method of claim 1 , further comprising prior to the commanding, by the processor, coupling the laser to a computer numeric control (CNC) tool.

3 . The method of claim 1 , wherein the predetermined set laser path is a three-dimensional path corresponding to the predefined geometric pattern of the contact surface, wherein the contact surface has a complex three-dimensional surface.

4 . The method of claim 3 , wherein the pulsed laser beam is substantially normal to the contact surface during operation.

5 . The method of claim 4 , wherein the single pulse fluence 10 mJ/mm2 and 205 mJ/mm2.

6 . The method of claim 4 , wherein the substrate is a stainless steel alloy.

7 . The method of claim 1 , wherein the substrate is a nickel alloy.

8 . The method of claim 1 , wherein the contact surface is at least one of a portion of a pressure side surface, a portion of a suction side surface, or a portion of a leading edge surface.

9 . The method of claim 1 , wherein the predefined geometric pattern comprises at least one of a linear array pattern, a perpendicular crosshatch pattern, or a rotating linear array.

10 . The method of claim 1 , wherein the pulsed laser beam comprises a wavelength of about 355 nm or about 1,064 nm.

11 . A surface treating system comprising:
a computer-based system configured to define a predefined geometric pattern on a contact surface; and a laser coupled to the computer-based system, the laser being configured to provide a pulsed laser beam to the contact surface, the pulsed laser beam having a single pulse fluence between 1 mJ/mm 2 and 1025 mJ/mm 2 , the laser being configured to generate a porous oxide layer on the contact surface of a substrate.

12 . The surface treating system of claim 11 , further comprising a computer numeric control (CNC) tool, the CNC tool being coupled to the laser and electrically coupled to the computer-based system.

13 . The surface treating system of claim 12 , wherein the laser is configured to travel along a three-dimensional path and surface treat a complex three-dimensional surface.

14 . The surface treating system of claim 12 , further comprising a shroud disposed around the laser and the CNC tool, and wherein the CNC tool and the laser are co-axial.

15 . A surface treated substrate, comprising:
a metallic alloy selected from a group consisting of a nickel alloy and a stainless steel alloy, the metallic alloy having a contact surface, comprising:
a topography having a plurality of linear arrays, each linear array having a height between 0.1 μm and 1 μm; and
an open pore structure with a pore distance between 0.05 and 1 μm; and
an oxide layer between 0.01 and 0.3 μm.

16 . The surface treated substrate of claim 15 , wherein each linear array further comprises a width less than 25 μm, and wherein a spacing between each linear array is between 10-50 μm.

17 . The surface treated substrate of claim 15 , wherein the metallic alloy is the nickel alloy.

18 . The surface treated substrate of claim 15 , wherein the metallic alloy is the stainless steel alloy.

19 . The surface treated substrate of claim 15 , wherein the nickel alloy is selected from the group consisting of American Society for Testing and Materials (ASTM) B443, ASTM B444, ASTM B704, ASTM B446, ASTM B670, and ASTM B637.

20 . The surface treated substrate of claim 15 , wherein the stainless steel alloy is selected from the group consisting of: American Society for Testing and Materials (ASTM) A240, ASTM A276, ASTM A320, and ASTM A479.

Assignees

• United Technologies Corp
• Nasa

Inventors

• Fang Xiaomei
• Hertel Christopher J
• Riehl John D
• Connell John W
• Palmieri Frank L
• Hopkins John W

Classifications

• B23K26/3584 Primary

  Increasing rugosity, i.e. roughening · CPC title

• F16B11/006

  by gluing (gluing of plastics material B29C65/48) · CPC title

• B23K26/0622

  by shaping pulses · CPC title

• B23K2103/05

  Stainless steel · CPC title

• B23K26/359 Primary

  by providing a line or line pattern, e.g. a dotted break initiation line · CPC title