Method for inflating micro-channels

Abstract

The invention belongs to the technical field of metal micro-forming, and in particular relates to a method for inflating micro-channels. The present invention is aimed at the problems of low process flexibility, single product type, and non-closed structure of the micro-channel when preparing metal micro-channels by micro-plastic forming of ultra-thin metal strips. The present invention uses a method combining numerical simulation and bond rolling experiment to analyze the effect of the hydrogen pressure and bond strength of the metal composite ultra-thin strip after bond rolling on the pore diameter of the micro-channel, and the corresponding relationship between the micro-channel pore diameter and the titanium hydride content, heating temperature, and bond strength of the metal composite ultra-thin strip is obtained.

Claims

1. A method for inflating a micro-channel, comprising steps of: Step (1) determining a quantitative relationship among titanium hydride content-temperature-hydrogen pressure and a relationship between a target pore size of the micro-channel and an amount of hydrogen released from decomposition of titanium hydride and a heating temperature; Step (2) engraving micro/nano grooves on a surface of an ultra-thin metal strip by a micro/nano scratcher, and performing surface cleaning treatment; Step (3) determining an amount of titanium hydride according to the quantitative relationship among titanium hydride content-temperature-hydrogen pressure and the relationship between the target pore size of the micro-channel and the amount of hydrogen released from decomposition of titanium hydride and the heating temperature determined in step (1), and the titanium hydride is placed in the micro/nano groove of the metal strip after the surface cleaning treatment in step (2); Step (4) covering another ultra-thin metal strip with identical size and identical surface cleaning treatment in step (2) on the ultra-thin metal strip in step (3), welding the edges of the two ultra-thin metal strips together by spot welding technology, and performing bond rolling; Step (5) heating the metal composite ultra-thin strip after bond rolling in step (4) under vacuum conditions, and keeping temperature to decompose the titanium hydride to release hydrogen, and by hydrogen pressure, plastic deformation occurs at the composite interface of the bond-rolled metal composite ultra-thin strip, and a tubular micro-channel structure is formed along the micro/nano groove engraved in step (2); Step (6) cutting the tubular micro-channel structure generated in step (5) at an appropriate position to obtain a tubular micro-channel product; wherein a specific process of determining the quantitative relationship among titanium hydride content-temperature-hydrogen pressure and the relationship between the target pore size of the micro-channel and the amount of hydrogen released from decomposition of titanium hydride and the heating temperature in the step (1) comprising: calculating an equilibrium hydrogen pressure when titanium hydride decomposes by thermodynamic method; analyzing the decomposition behavior of titanium hydride in the actual heating process by differential scanning calorimeter and thermal weight loss analyzer, so as to obtain the heating temperature to decompose and release hydrogen to determine the quantitative relationship between titanium hydride content-temperature-hydrogen pressure; by the method of combining numerical simulation and bond rolling experiment, analyzing the effect of the hydrogen pressure and bond strength of the metal composite ultra-thin strip after bond rolling on the pore size of the micro-channel, and the corresponding relationship between the pore size of the micro-channel and the content of titanium hydride, the heating temperature, and the bond strength of the metal composite ultra-thin strip is obtained.

2. The method for inflating the micro-channels according to claim 1, wherein the surface cleaning treatment in step (2) is immersing the ultra-thin metal strips engraved with micro/nano grooves in an acetone solution, cleaning the ultra-thin strip by ultrasonic cleaner to remove the scratch residue on its surface, to ensure that the composite interface is clean during the rolling process, and to improve the bond rolling effect of the ultra-thin metal strip.

3. The method for inflating the micro-channels according to claim 1, wherein a heating temperature in the step (5) is at a range of 500-700 C., and a keeping time is at a range of 10-30 min.

4. The method for inflating the micro-channels according to claim 1, wherein the titanium hydride in step (1) is capable of being replaced by zirconium hydride or other metal hydrides.

5. The method for inflating the micro-channels according to claim 1, wherein a thickness of the ultra-thin metal strip in the steps (1)-(5) is at a range of 20-200 m.

6. The method for inflating the micro-channels according to claim 1, wherein the material of the metal ultra-thin strip is at least one member selected from the group consisting of stainless steel, pure metal of titanium, copper, and aluminum; or an alloy of titanium, copper, and aluminum; wherein two metal ultra-thin strips have the identical material or a combination of different materials during bond rolling.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of a single channel structure of the present invention.

(2) FIG. 2 is a schematic diagram of a multi-channel structure of the present invention.

(3) FIG. 3 is a schematic diagram of a micro-channel product of FIG. 1 of the present invention.

(4) FIG. 4 is a schematic diagram of a micro-channel product of FIG. 2 of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(5) The following describes the technical solutions in the embodiments of the present invention clearly and completely with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

EMBODIMENT

(6) Referring to FIGS. 1-4, a method for inflating a micro-channel, comprising following steps of: Step (1) calculating an equilibrium hydrogen pressure when titanium hydride decomposes by thermodynamic method; analyzing the decomposition behavior of titanium hydride in the actual heating process by differential scanning calorimeter and thermal weight loss analyzer, so as to obtain the heating temperature to decompose and release hydrogen to determine the quantitative relationship between titanium hydride content-temperature-hydrogen pressure; by the method of combining numerical simulation and bond rolling experiment, analyzing the effect of the hydrogen pressure and bond strength of the metal composite ultra-thin strip after bond rolling on the pore size of the micro-channel, and the corresponding relationship between the pore size of the micro-channel and the content of titanium hydride, the heating temperature, and the bond strength of the metal composite ultra-thin strip is obtained. Step (2) engraving micro/nano grooves on a surface of a thin metal strip by a micro/nano scratcher, immersing the ultra-thin strip with micro/nano grooves in the acetone solution, and cleaning the ultra-thin strip by ultrasonic cleaner to remove the scratch residue on its surface; Step (3) determining an amount of titanium hydride according to the quantitative relationship among titanium hydride content-temperature-hydrogen pressure and the relationship between the target pore size of the micro-channel and the amount of hydrogen released from decomposition of titanium hydride and the heating temperature determined in step (1), and the titanium hydride powder is placed in the micro/nano groove of the metal strip after the surface cleaning treatment in step (2); Step (4) covering another ultra-thin metal strip with identical size and identical surface cleaning treatment in step (2) on the ultra-thin metal strip in step (3), welding the edges of the two ultra-thin metal strips together by spot welding technology, and performing bond rolling; Step (5) heating the metal composite ultra-thin strip after bond rolling in step (4) under vacuum conditions, and keeping temperature to decompose the titanium hydride to release hydrogen, and by hydrogen pressure, plastic deformation occurs at the composite interface of the bond-rolled metal composite ultra-thin strip, and a tubular micro-channel structure is formed along the micro/nano groove engraved in step (2); Step (6) cutting the tubular micro-channel structure generated in step (5) at an appropriate position to obtain a tubular micro-channel product.

(7) The single-channel structure shown in FIG. 1 and the multi-channel structure shown in FIG. 2 in this embodiment are only two special distributions of micro-channels. The number, direction, and distribution of the micro-channels involved in the present invention can be flexibly set according to requirements; all belong to the content protected by the present invention.

(8) In the embodiment, the heating temperature in step (5) is at a range of 500-700 C., and the holding time is at a range of 10-30 min; the titanium hydride in step (1) can be replaced by zirconium hydride or other metal hydrides, and in the step (1)-(5), the thickness of the metal ultra-thin strip is at a range of 20-200 m, such as 20 m, 50 m, 100 m, 150 m or 200 m. The ultra-thin metal strip material is stainless steel, and pure metals such as titanium, copper and aluminum or an alloy of titanium, copper, and aluminum. The two ultra-thin metal strips have the same material during bond rolling, or a combination of dissimilar materials.