TWI710416B - Method for using laser to sinter and coat polymer material on metal surface - Google Patents

Abstract

This creation discloses a method of using a laser to sinter and coat a polymer material on a metal surface, which includes: a. Grind the particle size of the polymer material powder to 40-90μm through a ball mill; b. Focus and scan with a laser source A metal substrate, generating a plurality of microstructures on the surface of the metal substrate, wherein the pulse frequency of the laser is 0.5-0.75kHz; and c. spreading the polymer material powder on the metal through a powder spreading system The surface of the substrate is directly irradiated on the metal substrate covered with the polymer powders for sintering by using a laser as a heat radiation source.

Description

Method for using laser to sinter and coat polymer material on metal surface

This creation belongs to the field of polymer material sintering, especially a method of using laser to sinter and coat polymer materials on metal surfaces and improve the adhesion of polymer materials to metal surfaces.

According to, with the continuous fermentation of smart manufacturing, green energy and environmental protection issues, smart manufacturing, solar energy, green lighting, electric vehicles and other industries have begun to pay attention to the development of power module management, and their manufacturing processes are gradually moving toward high power, small size and Thinning development. Therefore, in order to simultaneously meet the requirements of lightness, thinness, shortness and convenient transportation, high density, high power, high transmission speed and high efficiency, the heat dissipation efficiency of packaging technology and corresponding packaging materials is a problem that cannot be ignored.

Moreover, because selective laser sintering has the advantage of rapid prototyping and manufacturing for polymer materials, metals, ceramics and composite materials. Therefore, common types of thermal conductive materials such as metal materials, ceramic materials and polymer materials, and metal materials and ceramic materials based on heat dissipation considerations will face the following problems: 1. Metal materials have poor chemical resistance and electrical insulation, which cannot meet the heat dissipation requirements of electrical insulation and chemical corrosion occasions. 2. Although inorganic ceramic materials have good insulation properties, they have high processing costs and poor impact resistance. On the other hand, although graphite materials have excellent thermal conductivity, they have poor insulation and mechanical properties.

Therefore, the above-mentioned thermally conductive materials are limited in the development of industrial technologies such as microelectronic packaging, electrical insulation, and LED lighting due to their own properties, while polymer materials have good mechanical properties and fatigue resistance, and are excellent Electrical insulation and chemical resistance, light weight and widely used.

Among the polymer materials, thermoplastics have the most development. The most representative one is polyamide, commonly known as nylon (Nylon), and its English name is Polyamide (PA), which contains repeating amide groups on the main chain of the molecule—[ NHCO]—The general term for thermoplastic resins, which are widely used in the automotive and electronic industries to replace metals, with the goal of making lighter and cheaper components. At the same time, nylon is a polymer material with high Tg glass transition temperature ~ 220 ^o C, high melting point temperature ~ 250 ^o C and low thermal expansion coefficient 2.7 ~ 7.2×10 ^-5 /K, and has high temperature resistance and excellent chemical resistance. Corrosion and high insulation. However, considering the heat dissipation properties, the thermal conductivity of nylon is about 0.29k/W/(m.K) and does not have a good heat dissipation capacity. Therefore, the industry mostly uses mixed metal, ceramic or carbon powder production as a solution.

However, in order to coat the polymer material on the metal substrate, the bonding between the two materials is often due to the large difference in melting point temperature. As a result, the bonding strength of the two materials is often poor when combined, resulting in the difference between the polymer material and the metal material. The adhesion between them is extremely poor. On the other hand, polymer materials have a low absorption rate for fiber lasers, so most of them are sintered through CO ₂ lasers. However, the transmission medium of CO ₂ lasers is air, which can only be transmitted in a straight line and must rely on mirrors. Change the transmission direction, therefore, it is susceptible to the influence of the external environment, and the reflector needs to be maintained and maintained frequently.

In view of this, the inventor felt that it was not perfect and exhausted his mind and painstaking research. Based on his accumulated experience in this industry for many years, he provided a method for sintering and coating polymer materials on metal surfaces by laser. In order to improve the lack of the above-mentioned conventional technology.

One objective of the present invention is to provide a method for sintering and coating polymer materials on metal surfaces by using lasers to improve the adhesion of polymer materials when sintering and coating on metal surfaces.

Therefore, this creation discloses a method of using lasers to sinter and coat polymer materials on metal surfaces, which includes: a. Grinding the particle size of the polymer powders to 40-90μm through a ball mill; b. Using a laser source Focus and scan a metal substrate to produce multiple microstructures on the surface of the metal substrate. The pulse frequency of the laser is 0.5-0.75kHz; and c. Spread the polymer material powder on The surface of the metal substrate uses a laser as a heat radiation source to directly irradiate the metal substrate covered with the polymer material powders for sintering.

Preferably, the material of the polymer powder is polylactic acid (PLA), resin (ABS), polyamide (nylon)-6, polyamide (PA) 66 (Nylon-66), polyvinyl alcohol (PVA), polystyrene (PS), acrylic (PMMA) one of them.

Preferably, the material of the polymer material powder is a nylon-based mixed polymer material powder formed by mixing one of copper, aluminum, zinc, gold, silver, iron, and nickel.

Preferably, the material of the polymer material powder is one of nylon-based mixed alumina, aluminum nitride, silicon nitride, silicon carbide, magnesium oxide, and silicon dioxide to form a mixed polymer material powder .

Preferably, the microstructures are arranged at intervals, and the distance between the microstructures is 1mm.

Preferably, the material of the metal substrate is one of iron-based, nickel-based, cobalt-based, chromium-based, molybdenum-based, aluminum-based, and copper-based metals, or an alloy material thereof.

Preferably, the wavelength range of the laser is 400 nm to 11000 nm.

Preferably, the thickness of the polymer material powder after sintering is 0.2-10 mm.

In this way, through the method provided by the present invention, the polymer material can be sintered and coated on the metal substrate layer by layer by laser without being easy to fall off, thereby improving the adhesion of the polymer material to meet the requirements of various industries. The surface of metal materials needs to be coated with polymer materials.

In order to enable your reviewer to understand the content of the present invention clearly, please refer to the following description and drawings.

Please refer to Figures 1 to 3, which are the steps of the creation of the preferred embodiment, the schematic diagram of the laser sintering device, and the schematic diagram of the metal substrate and polymer powder after sintering. As shown in the figure, this creation discloses a method of using a laser to sinter and coat a polymer material on a metal surface. It first grinds the particle size of the polymer material powder 3 to 40-90 μm through a ball mill (step S01). Among them, the material of the polymer powder 3 is polylactic acid (PLA), resin (ABS), polyamide (nylon)-6, polyamide (PA) 66 (Nylon-66), polyvinyl alcohol ( PVA), polystyrene (PS), acrylic (PMMA) or nylon based mixed copper, aluminum, zinc, gold, silver, iron, nickel, aluminum oxide, aluminum nitride, silicon nitride, silicon carbide, oxide One of magnesium and silicon dioxide. In this embodiment, nylon is used as an example, but it is not limited to this. The laser used in this embodiment is based on an optical fiber laser. However, it can also be a CO ₂ laser and is not limited.

Then, the laser source 1 is transmitted through the optical fiber 2 to focus and scan a metal substrate 4 to produce a plurality of microstructures 41 on the surface of the metal substrate 4 (step S02). In this embodiment, the microstructures 41 is arranged at intervals, and the distance d between the microstructures 41 is 1mm, as shown in Figure 3. The pulse frequency of the fiber laser used is 0.5-0.75kHz, the pulse width is 750μs, and the wavelength range is It is 400 nm~11000nm, power 150W, scanning speed 20mm/s, scanning range 100mm × 100mm. Moreover, the material of the metal substrate 4 can be one of iron-based, nickel-based, cobalt-based, chromium-based, molybdenum-based, aluminum-based, and copper-based metals or alloy materials thereof. In this embodiment, stainless steel is used as an example, but Not limited to this.

Finally, through the powder spreading system, the polymer material powder 3 is spread on the surface of the metal substrate 4, and an optical fiber laser is used as a heat radiation source to directly irradiate the metal substrate on which the polymer material powder 3 is spread. Sintering is performed on the material 4 (step S03), and the thickness t of the polymer material powder 3 can reach 0.2-10 mm after sintering.

The following provides a number of different embodiments, and please refer to Figure 4 and Table 1 below, which are the microstructured optical images produced by the laser surface treatment in the various embodiments of the preferred embodiments and the various embodiments The attached area data sheet.

Example 1

The detailed experimental procedure of this embodiment is to first grind the particle size of the polymer material powder 3 of nylon to 40-90μm through a ball mill, and then use a fiber laser power of 150W, a scanning speed of 20mm/s, a scanning distance of 1mm, and a pulse frequency Under the conditions of 0.04375 kHz, pulse width 750μs, and scanning range of 100×100 mm ² , the stainless steel metal substrate 4 is surface-treated, and these microstructures 41 are generated on the surface, as shown in part (a) of Figure 4 As shown, the polymer material powder 3 is spread on the surface-treated metal substrate 4 through the powder spreading system, and then the optical fiber laser 20-100W is used as the heat radiation light source, and the scanning speed is 70 mm / s, scanning pitch 0.025mm, 0.75KHz pulse frequency, pulse width of 500μs, 100 × 100 mm ² condition of the scanning range, for direct exposure to 4 covered with powder of such polymer material of the metal substrate 3 Sintering, and the sintering thickness t is set to 1 mm.

Example 2

The detailed experimental procedure of this embodiment is to first grind the particle size of the polymer material powder 3 of nylon to 40-90μm through a ball mill, and then use a fiber laser power of 150W, a scanning speed of 20mm/s, a scanning distance of 1mm, and a pulse frequency Under the conditions of 0.0875kHz, pulse width 750μs, and scanning range of 100×100 mm ^2, the surface treatment of the metal base material 4 of stainless steel will produce these microstructures 41 on the surface, as shown in part (b) of Figure 4 As shown, the polymer material powder 3 is spread on the surface-treated metal substrate 4 through the powder spreading system, and then the optical fiber laser 20-100W is used as the heat radiation light source, and the scanning speed is 70 mm / s, scanning pitch 0.025mm, 0.75KHz pulse frequency, pulse width of 500μs, 100 × 100 mm ² condition of the scanning range, for direct exposure to 4 covered with powder of such polymer material of the metal substrate 3 Sintering, and the sintering thickness t is set to 1 mm.

Example 3

The detailed experimental procedure of this embodiment is to first grind the particle size of the polymer material powder 3 of nylon to 40-90μm through a ball mill, and then use a fiber laser power of 150W, a scanning speed of 20mm/s, a scanning distance of 1mm, and a pulse frequency Under the conditions of 0.175kHz, pulse width of 750μs, and scanning range of 100×100 mm ^2, the surface treatment of the metal base material 4 of stainless steel will produce these microstructures 41 on the surface, as shown in part (c) of Figure 4 As shown, the polymer material powder 3 is spread on the surface-treated metal substrate 4 through the powder spreading system, and then the optical fiber laser 20-100W is used as the heat radiation light source, and the scanning speed is 70 mm / s, scanning pitch 0.025mm, 0.75KHz pulse frequency, pulse width of 500μs, 100 × 100 mm ² condition of the scanning range, for direct exposure to 4 covered with powder of such polymer material of the metal substrate 3 Sintering, and the sintering thickness t is set to 1 mm.

Example 4

The detailed experimental procedure of this embodiment is to first grind the particle size of the polymer material powder 3 of nylon to 40-90μm through a ball mill, and then use a fiber laser power of 150W, a scanning speed of 20mm/s, a scanning distance of 1mm, and a pulse frequency Under the conditions of 0.25kHz, pulse width 750μs, and scanning range of 100×100 mm ² , the stainless steel metal substrate 4 is surface treated, and the microstructures 41 are generated on the surface, as shown in part (d) of Figure 4 As shown, the polymer material powder 3 is spread on the surface-treated metal substrate 4 through the powder spreading system, and then the optical fiber laser 20-100W is used as the heat radiation light source, and the scanning speed is 70 mm / s, scanning pitch 0.025mm, 0.75KHz pulse frequency, pulse width of 500μs, 100 × 100 mm ² condition of the scanning range, for direct exposure to 4 covered with powder of such polymer material of the metal substrate 3 Sintering, and the sintering thickness t is set to 1 mm.

Example 5

The detailed experimental procedure of this embodiment is to first grind the particle size of the polymer material powder 3 of nylon to 40-90μm through a ball mill, and then use a fiber laser power of 150W, a scanning speed of 20mm/s, a scanning distance of 1mm, and a pulse frequency Under the condition of 0.5kHz, pulse width of 750μs, and scanning range of 100×100 mm ^2, the surface treatment of the metal substrate 4 of stainless steel will produce the microstructures 41 on the surface, as shown in part (e) of Figure 4 As shown, the polymer material powder 3 is spread on the surface-treated metal substrate 4 through the powder spreading system, and then the optical fiber laser 20-100W is used as the heat radiation light source, and the scanning speed is 70 mm / s, scanning pitch 0.025mm, 0.75KHz pulse frequency, pulse width of 500μs, 100 × 100 mm ² condition of the scanning range, for direct exposure to 4 covered with powder of such polymer material of the metal substrate 3 Sintering, and the sintering thickness t is set to 1 mm.

Example 6

The detailed experimental procedure of this embodiment is to first grind the particle size of the polymer material powder 3 of nylon to 40-90μm through a ball mill, and then use a fiber laser power of 150W, a scanning speed of 20mm/s, a scanning distance of 1mm, and a pulse frequency Under the conditions of 0.75kHz, pulse width 750μs, and scanning range of 100×100 mm ² , the metal substrate 4 of stainless steel is surface treated, and the microstructures 41 are generated on the surface, as shown in part (f) of Figure 4 As shown, the polymer material powder 3 is spread on the surface-treated metal substrate 4 through the powder spreading system, and then the optical fiber laser 20-100W is used as the heat radiation light source, and the scanning speed is 70 mm / s, scanning pitch 0.025mm, 0.75KHz pulse frequency, pulse width of 500μs, 100 × 100 mm ² condition of the scanning range, for direct exposure to 4 covered with powder of such polymer material of the metal substrate 3 Sintering, and the sintering thickness t is set to 1 mm.

Example 7

The detailed experimental procedure of this embodiment is to first grind the particle size of the polymer material powder 3 of nylon to 40-90μm through a ball mill, and then use a fiber laser power of 150W, a scanning speed of 20mm/s, a scanning distance of 1mm, and a pulse frequency Under the conditions of 1kHz, pulse width 750μs, and scanning range of 100×100 mm ² , the metal substrate 4 of stainless steel is surface treated, and these microstructures 41 are generated on the surface, as shown in part (g) of Figure 4 As shown, the polymer material powder 3 is spread on the surface-treated metal substrate 4 through the powder spreading system, and then the optical fiber laser 20-100W is used as the heat radiation source, and the scanning speed is 70 mm / s, scanning pitch 0.025mm, 0.75KHz pulse frequency, pulse width of 500μs, 100 × 100 mm ² range of scanning conditions, direct exposure to the sintering covered with polymer material powder 4 such that the metal substrate 3 , And the sintering thickness t is set to 1 mm.

Example 8

The detailed experimental procedure of this embodiment is to first grind the particle size of the polymer material powder 3 of nylon to 40-90μm through a ball mill, and then use a fiber laser power of 150W, a scanning speed of 20mm/s, a scanning distance of 1mm, and a pulse frequency Under the conditions of 2kHz, pulse width 750μs, and scanning range of 100×100 mm ² , the stainless steel metal substrate 4 is surface treated, and these microstructures 41 are generated on the surface, as shown in part (h) of Figure 4 As shown, the polymer material powder 3 is spread on the surface-treated metal substrate 4 through the powder spreading system, and then the optical fiber laser 20-100W is used as the heat radiation source, and the scanning speed is 70 mm / s, scanning pitch 0.025mm, 0.75KHz pulse frequency, pulse width of 500μs, 100 × 100 mm ² range of scanning conditions, direct exposure to the sintering covered with polymer material powder 4 such that the metal substrate 3 , And the sintering thickness t is set to 1 mm.

Control example

The detailed experimental procedure of this comparative example is to first grind the particle size of the polymer material powder 3 of nylon to 40-90 μm through a ball mill, and no treatment is performed on the surface of the metal substrate 4 of stainless steel, as in the fourth As shown in part (i) of the figure, the polymer material powder 3 is spread on the metal substrate 4 without any treatment through the powder spreading system, and then the optical fiber laser 20-100W is used as the heat radiation source. And under the conditions of a scanning speed of 70 mm/s, a scanning distance of 0.025 mm, a pulse frequency of 0.75 kHz, a pulse width of 500 μs, and a scanning range of 100×100 mm ² , it is directly irradiated on the metal covered with the polymer powder 3 Sintering is performed on the substrate 4, and the sintering thickness is set to 1 mm.

Table 1 Group Pulse frequency Pulse Width Laser power Scan speed Scan pitch Attachment area Example 1 0.04375 kHz 750μs 150 W 20mm/s 1mm 0% Example 2 0.0875 kHz 750μs 150 W 20mm/s 1mm 0% Example 3 0.175 kHz 750μs 150 W 20mm/s 1mm 0% Example 4 0.25 kHz 750μs 150 W 20mm/s 1mm 0% Example 5 0.5 kHz 750μs 150 W 20mm/s 1mm 66% Example 6 0.75 kHz 750μs 150 W 20mm/s 1mm 90% Example 7 1.0 kHz 750μs 150 W 20mm/s 1mm 0% Example 8 2.0 kHz 750μs 150 W 20mm/s 1mm 0% Control example - - - - - 0%

From the above data, it can be seen that the sintering coating process made according to the experimental steps of Example 5 and Example 6 has a significant improvement in the adhesion of the polymer, that is, when the metal substrate 4 is producing the In the process of waiting for the microstructure 41, the pulse frequency of the fiber laser must be between 0.5 and 0.75 kHz, so that the polymer material powder 3 can be effectively attached to the metal substrate 4, and the data sheet can also prove Under the conditions provided by the present invention, the defects of conventional lasers have been solved, and the adhesion of polymers to metals can be improved, and the thickness can reach more than 1 mm, which shows that the method provided by the present invention has its advantages .

However, the above are only the preferred embodiments of the present invention, and are not used to limit the scope of implementation of this creation; therefore, the equivalent changes and modifications made without departing from the spirit and scope of the present invention should be covered in Within the scope of the patent of the present invention.

1: Laser source 2: optical fiber 3: Polymer material powder 4: Metal substrate 41: Microstructure S01~S03: steps d: spacing t: thickness

Figure 1 is a diagram of the steps of creating a preferred embodiment. Figure 2 is a schematic diagram of a laser sintering device according to a preferred embodiment of the creation. Figure 3 is a schematic diagram of the sintered metal substrate and polymer powder of the preferred embodiment of the creation. Figure 4 is the optical image of the microstructure produced by the laser surface treatment in each embodiment of the creation of the preferred embodiment.

S01~S03: steps

Claims (9)

A method for sintering and coating a polymer material on a metal surface using a laser, which comprises: a. Grinding the particle size of a plurality of polymer material powders to 40-90 μm through a ball mill; b. Focusing and scanning a metal substrate with a laser source Material, multiple microstructures are produced on the surface of the metal substrate, wherein the pulse frequency of the laser is 0.5-0.75kHz, the pulse width is 750μs, the laser power is 150W, the scanning speed is 20mm/s, and the scanning interval is 1mm; and c. Spread the polymer material powder on the surface of the metal substrate through the powder spreading system, and use a laser 20-100W as the heat radiation source, and the pulse width is 500μs, the scanning speed is 70mm/s, and the scanning distance is 0.025mm. Under the condition of frequency 0.75kHz, directly irradiate the metal substrate covered with the polymer material powder for sintering. Such as the method described in item 1 of the scope of patent application, wherein the material of the polymer material powder is polylactic acid (PLA), resin (ABS), polyamide (nylon)-6, polyamide (PA) 66 (Nylon-66), polyvinyl alcohol (PVA), polystyrene (PS), acrylic (PMMA) one of them. For example, the method described in item 1 of the scope of patent application, wherein the material of the polymer material powder is nylon-based mixed with one of copper, aluminum, zinc, gold, silver, iron, and nickel, and the resulting mixture is high Molecular material powder. For the method described in item 1 of the scope of patent application, wherein the material of the polymer material powder is one of nylon-based mixed diamond, graphite, carbon fiber and graphene to form a mixed polymer material powder. Such as the method described in item 1 of the scope of patent application, wherein the material of the polymer material powder is nylon-based mixed alumina, aluminum nitride, silicon nitride, silicon carbide, magnesium oxide, and silicon dioxide. One, and the mixed polymer material powder is formed. The method according to any one of items 1 to 5 in the scope of patent application, wherein the microstructures are arranged at intervals, and the distance between the microstructures is 1mm. According to the method described in item 6 of the scope of patent application, wherein the material of the metal substrate is one of iron-based, nickel-based, cobalt-based, chromium-based, molybdenum-based, aluminum-based, and copper-based metals or alloy materials thereof. The method described in item 7 of the scope of patent application, wherein the wavelength range of the laser is 400nm~11000nm. The method described in item 8 of the scope of patent application, wherein the thickness of the polymer material powder after sintering is 0.2-10mm.

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