Micro-group hole array special-shaped gold strip and preparation method

Abstract

This invention discloses a micro-pore array irregular gold strip and its preparation method, belonging to the field of micro-pore metal strip preparation and processing technology. The micro-pore array irregular gold strip is characterized by its porous structure, small size, smooth hole walls and surface, and high dimensional accuracy. The material used is pure gold strengthened with ppm-level trace alloying elements. A gold sheet blank is formed through intermediate alloy pre-melting and continuous casting and rolling. Internal defects in the gold sheet blank are eliminated through homogenization annealing, resulting in a redistribution of the alloy composition. Then, an ultra-thin gold sheet is formed through two-stage precision rolling. Holes with smooth walls and meeting dimensional standards are formed using stamping and a femtosecond laser. Finally, the sheet is slitting and shearing machine to cut the sheet into finished irregular gold strips. This preparation method can greatly reduce processing losses, save precious metal resources, and is suitable for mass production. The resulting micro-pore array irregular gold strip has high strength, a smooth surface, and good hole size consistency, making it suitable for the microelectronics and information industry.

Description

Technical Field

[0001] This invention belongs to the field of precious metal irregular strip preparation and processing technology, and particularly relates to a micro-pore array irregular gold strip and its preparation method. Background Technology

[0002] Micro-pore array irregular gold ribbon has advantages such as light weight, high communication frequency, good thermal conductivity and stable chemical properties. It is a new generation of high-tech material that can replace traditional materials such as gold wire, gold ribbon and gold sheet. It can be used in jewelry, electronic information, medical, cable, new energy, intelligent manufacturing and other fields.

[0003] Due to its unique structural characteristics, the micro-pore array irregular gold ribbon is classified as a difficult-to-process material with high precision, high surface quality, low loss, and extremely low yield. Its preparation and processing technology has always been a key focus and challenge for industry professionals.

[0004] The processing of ultrathin metal materials is limited by the precision of machining. Electrodeposition is generally used to prepare ultrathin sheets, such as CN115246007A, which describes a method for preparing micron-sized gold nanosheets, using hydrothermal synthesis to prepare micron-sized single-crystal gold nanosheets for use in catalysis and surface-enhanced Raman scattering (SERS) applications; and CN112593261A, which discloses a gold foil manufacturing scheme, preparing a gold foil layer on a copper foil substrate through electrolysis. All of these methods require chemical reagents, which can cause environmental pollution, and the surface quality is still somewhat inferior to that of mechanically processed strips. Regarding hole preparation, CN116323087A discloses a laser-drilled tape hole processing device, which offers high efficiency and hole quality, but is not suitable for precious metals due to the high loss of precious metals during the process.

[0005] Therefore, it is essential to develop a method for preparing irregular gold ribbons with micro-pore arrays mainly through machining. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a micro-pore array irregular gold strip and its preparation method. The irregular gold strip of the invention has the characteristics of pore arrangement, high dimensional accuracy, thin thickness and high surface cleanliness. The advantages of its preparation method are low precious metal loss, high processing efficiency, mirror-like surface cleanliness, high processing accuracy, and mass production capability.

[0007] The technical problem to be solved by this invention is achieved by the following technical solution:

[0008] The structural characteristics of the micro-pore array irregular gold ribbon prepared by this invention are as follows: the ribbon width is 0.1-2 mm, the thickness is 0.01-0.05 mm, the length is 50-1000 m, the pore shape is circular or square, the pore diameter or side length is 0.01-0.05 mm, the transverse width is 0.01-0.05 mm, the longitudinal width is 0.01-0.05 mm, the surface has a mirror effect, and there are no scratches, pits or protrusions exceeding 10% of the ribbon width.

[0009] The chemical composition of the micro-pore array irregular gold ribbon prepared by this invention is as follows: Au ≥ 99wt%, and the added alloying elements are: 3-25ppm Cu, Ni, Zn transition elements, 5-18ppm Ag, Pt, Pd noble metal elements, or one or two of La, Ce, Sm, Gd rare earth elements, or 8-25ppm La, Ce, Sm, Gd rare earth elements.

[0010] The fabrication method of the micro-pore array irregular gold ribbon is as follows:

[0011] (1) Alloying pre-melting: Gold-based master alloy and high-purity gold are placed in a graphite crucible according to the ratio, heated to 1100-1300℃, held for 15-30 min, cooled naturally to 500-800℃, heated again to 1100-1300℃, held for 20-40 min, and cooled with the furnace.

[0012] (2) Continuous casting and rolling: A continuous casting and rolling mill is used, with a single furnace feed rate of 2000-5000g, a continuous casting temperature of 1050-1250℃, a holding time of 20-40min after reaching the temperature, and a vacuum degree controlled at 10. -2 ~1Pa, drawing speed 10mm / min~100mm / min, rolling reduction 15~35%, thickness to 0.1~0.5mm.

[0013] (3) Homogenization annealing: box furnace, temperature 500~650℃, holding time 30~60min.

[0014] (4) Fine rolling: A continuous take-up double-roll double precision rolling mill is used. The first pass has a rolling reduction of 10-20%, the second pass has a rolling reduction of 5-10%, and the line speed is 1m / min to 30m / min.

[0015] (5) Stamping: An automatic loading and unloading stamping machine is used. The downward stamping speed is finely adjusted to 0.1–0.5 m / min, the stamping force is 0.2–2 N, the number of stamping passes per hole is 2, the stamping spacing is 0.05–0.1 mm, the feeding length is 20 cm per unit, and one unit is fed at a time. Cooling method: spray water cooling. The flatness after stamping reaches 0.005–0.01 mm / 100 mm. 2 The verticality of the cross-section is 0.001~0.003mm / mm.2 Inclination < 1°.

[0016] (6) Femtosecond laser hole repair: Process parameters for femtosecond laser hole repair: processing power 15-40W, laser processing speed 2800-3500r·min -1 The laser frequency is 200–450 kHz, the aperture angle is 28–82°, and the single feed rate is 0.01–0.05 mm.

[0017] (7) Slitting, shearing force 0.1N~5N, longitudinal shearing speed 100mm / min~500mm / min, longitudinal shearing width error ±0.002mm.

[0018] The beneficial effects of the method proposed in this invention are as follows:

[0019] This invention successfully prepared a micro-hole array-shaped gold strip through seven steps: continuous casting and rolling, homogenization annealing, fine rolling, stamping, laser drilling, and slitting, using a micro-alloying strengthened gold matrix. The resulting gold strip samples exhibited small dimensional deviations, smooth surfaces, and high-quality hole walls, comparable to similar products from abroad. This preparation method not only overcomes the technological bottleneck in the preparation of high-precision precious metal shaped strips but also fills the gap in domestically produced ultra-thin shaped strips. The invention combines machining and femtosecond laser processing, reducing precious metal loss while meeting the requirements for high processing precision and high surface quality. Detailed Implementation

[0020] Example 1

[0021] The composition of the gold band is: Au > 99wt%, with added alloying elements including 10ppm Cu, 15ppm Ag, 5ppm Pt, and 10ppm La.

[0022] (1) Alloying pre-melting: Gold-based master alloy and high-purity gold are placed in a graphite crucible according to the ratio, heated to 1100℃, held for 30 min, cooled naturally to 600℃, heated again to 1150℃, held for 30 min, and cooled with the furnace.

[0023] (2) Continuous casting and rolling: A continuous casting and rolling mill is used, with a single furnace feed rate of 2000g, a continuous casting temperature of 1100℃, a holding time of 30min after reaching the temperature, and a vacuum degree controlled at 10. -1 Pa, drawing speed 23 mm / min, rolling reduction 15%, thickness to 0.2 mm.

[0024] (3) Homogenization annealing: box furnace, temperature 500℃, holding time 35min.

[0025] (4) Fine rolling: The continuous take-up double-roll double precision rolling mill is used. The first pass has a rolling reduction of 15%, the second pass has a rolling reduction of 5%, and the line speed is 5m / min.

[0026] (5) Stamping: An automatic loading and unloading stamping machine is used. The downward stamping speed is finely adjusted to 0.2 m / min, the stamping force is 0.5 N, the number of stamping passes per hole is 2, the stamping spacing is 0.05 mm, the feeding length is 20 cm per unit, and one unit is fed at a time. The cooling method is spray water cooling. The flatness after stamping reaches 0.005 mm / 100 mm. 2 The verticality of the cross-section is 0.001 mm / mm. 2 Inclination < 1°.

[0027] (6) Femtosecond laser hole repair: Process parameters for femtosecond laser hole repair: processing power 25W, laser processing speed 2200r·min -1 The laser frequency is 320KHz, the aperture angle is 40°, and the single feed rate is 0.02mm.

[0028] (7) Slitting, shearing force 0.3N, longitudinal shearing speed 120mm / min, longitudinal shearing width error ±0.002mm.

[0029] The irregularly shaped strip prepared according to the above process has the following characteristics: width 0.2mm, thickness 0.03mm, length 150m, hole type round or square, hole diameter or side length 0.02mm, transverse strip width 0.01mm, longitudinal strip width 0.5mm, and a mirror-like surface with no scratches exceeding 10% of the strip.

[0030] Example 2

[0031] The composition of the gold band is: Au > 99wt%, with added alloying elements of 25ppm Ni, 15ppm Pd, 20ppm Ce and 5ppm Gd.

[0032] (1) Alloying pre-melting: Gold-based master alloy and high-purity gold are placed in a graphite crucible according to the ratio, heated to 1200℃, held for 30 min, cooled naturally to 650℃, heated again to 1200℃, held for 40 min, and cooled with the furnace.

[0033] (2) Continuous casting and rolling: A continuous casting and rolling mill is used, with a single furnace feed rate of 5000g, a continuous casting temperature of 1250℃, a holding time of 40min after reaching the temperature, and a vacuum degree controlled at 10. -2 Pa, drawing speed 100 mm / min, rolling reduction 35%, thickness to 0.2 mm.

[0034] (3) Heat treatment: box furnace, temperature 600℃, holding time 30min, atmospheric environment.

[0035] (4) Fine rolling: The continuous take-up double-roll double precision rolling mill is used. The first pass has a rolling reduction of 20%, the second pass has a rolling reduction of 10%, and the running speed is 20m / min.

[0036] (5) Stamping: An automatic loading and unloading stamping machine is used. The downward stamping speed is finely adjusted to 0.2 m / min, the stamping force is 1.5 N, the number of stamping passes per hole is 2, the stamping spacing is 0.1 mm, the feeding length is 20 cm per unit, and one unit is fed at a time. The cooling method is spray water cooling. The flatness after stamping reaches 0.01 mm / 100 mm. 2 The verticality of the cross-section is 0.003 mm / mm. 2 Inclination < 1°.

[0037] (6) Femtosecond laser hole repair: Process parameters for femtosecond laser hole repair: processing power 45W, laser frequency 400KHz, laser processing speed 3500r·min -1 The aperture angle is 65° and the single feed rate is 0.055 mm.

[0038] (7) Slitting, shearing force 3.5N, longitudinal shearing speed 500mm / min, longitudinal shearing width error ±0.002mm.

[0039] The irregular strip prepared according to the above process has the following characteristics: width 2mm, thickness 0.05mm, length 1000m, hole type round or square, hole diameter or side length 0.05mm, transverse strip width 0.05mm, longitudinal strip width 1.5mm, surface with mirror effect, and no scratches exceeding 10% of the strip.

[0040] The above-described preferred embodiments of the present invention are for illustrative purposes only and are not intended to limit the technical solutions described in the embodiments of the present invention. Any equivalent substitutions or modifications made by those skilled in the art without departing from the concept of the present invention, and with the same performance or purpose, should be considered to fall within the scope of disclosure and protection of the present invention.

Claims

1. A method for preparing a micro-aperture array irregular gold ribbon, characterized in that, Includes the following steps: Step 1, pre-melting by alloying High-purity gold is strengthened by microalloying to obtain a gold-based alloy AuX, wherein Au ≥ 99 wt% of the gold-based alloy, and X is an added alloying element, including: 3-25 ppm of one of the transition elements Cu, Ni, and Zn; 5-18 ppm of one or two of the noble metal elements Ag, Pt, and Pd; and 8-25 ppm of one or two of the rare earth elements La, Ce, Sm, and Gd. Step 2, continuous casting and rolling; Step 3, homogenization annealing; Step 4, fine rolling; Step 5, stamping; Step 6, femtosecond laser hole repair; Step 7: Cut into strips.

2. The method for preparing the micro-pore array irregular gold ribbon according to claim 1, characterized in that, Step 1 includes: The AuX is placed in a graphite crucible according to the specified ratio, heated to 1100-1300℃, held for 15-30 minutes, cooled naturally to 500-800℃, heated again to 1100-1300℃, held for 20-40 minutes, and then cooled with the furnace.

3. The method for preparing the micro-pore array irregular gold ribbon according to claim 1, characterized in that, Step 2 includes: Single furnace charge: 2000–5000 g; continuous casting temperature: 1050–1250℃; holding time: 20–40 min; vacuum level: controlled at 10. -2 ~1Pa, drawing speed 10~100mm / min, rolling reduction 15~35%, thickness to 0.1~0.5mm.

4. The method for preparing the micro-aperture array irregular gold ribbon according to claim 1, characterized in that, Step 3 includes: The homogenization annealing is performed in a box furnace at a temperature of 500–650°C and a holding time of 30–60 minutes.

5. The method for preparing the micro-pore array irregular gold ribbon according to claim 1, characterized in that, Step 4 includes: It adopts a continuous take-up twin-roll double precision rolling mill. The first pass has a rolling reduction of 10-20%, the second pass has a rolling reduction of 5-10%, and the line speed is 1m / min to 30m / min.

6. The method for preparing the micro-pore array irregular gold ribbon according to claim 5, characterized in that: The roll runout of the twin-roll double-jointed precision rolling mill is ≤0.002mm, the roll surface roughness is 0.2μm, and the thickness accuracy is controlled within ±0.001mm.

7. The method for preparing the micro-pore array irregular gold ribbon according to claim 1, characterized in that, Step 5 includes: The automatic loading and unloading stamping equipment is used, with a fine-tuned downward stamping speed of 0.1–0.5 mm / min, a stamping force of 0.2–2 N, two stamping passes per hole, a stamping spacing of 0.05–0.1 mm, a feeding length of 20 cm per unit, and one unit fed at a time. Cooling is achieved through water spraying. The flatness after stamping reaches 0.005–0.01 mm / 100 mm. 2 The verticality of the cross-section is 0.001~0.003mm / mm. 2 Inclination < 1°.

8. The method for preparing the micro-pore array irregular gold ribbon according to claim 1, characterized in that, The process parameters for step 6 include: Processing power 15-40W, laser processing speed 2800-3500 r·min -1 The laser frequency is 200–450 kHz, the aperture angle is 28–82°, and the single feed rate is 0.01–0.05 mm.

9. The method for preparing the micro-pore array irregular gold ribbon according to claim 1, characterized in that, Step 7 includes: Shearing force 0.1~5N, longitudinal shearing speed 100~500mm / min, longitudinal shearing width error ±0.002mm.

10. A micro-pore array irregular gold ribbon prepared by the method of any one of claims 1-9, characterized in that: The strip has a width of 0.1–2 mm, a thickness of 0.01–0.05 mm, and a length of 50–1000 m; The strip has a circular or square hole shape, with a hole diameter or side length of 0.01 to 0.05 mm; The transverse width of the strip is 0.01–0.05 mm, and the longitudinal width is 0.01–0.05 mm. The surface of the strip has a mirror finish and is free of scratches, dents, and protrusions exceeding 10% of the strip width.