JP2021021114A - Laminate having aluminum-magnesium alloy thermal spray layer and method of making metal thermal spray layer - Google Patents

Abstract

To discover thermal spray conditions to allow continuous aluminum-magnesium alloy thermal spraying and provide a laminate having undergone an anticorrosive treatment with an alloy thus obtained.SOLUTION: A laminate at least has a base material, a resin layer containing particles with an average particle size of 10-150 μm, and an aluminum-magnesium alloy (mass ratio 90:10-99.5:0.5) thermal spray layer, in the stated order.SELECTED DRAWING: None

Description

The present invention relates to a laminate having an aluminum-magnesium alloy sprayed layer and a method for producing the metal sprayed layer thereof.

When performing metal spraying for the purpose of preventing corrosion of steel structures, it is necessary to roughen the surface of the base material in order to ensure adhesion to the base material. Blasting is one of the roughening treatment methods, but blasting (ISO8501-1) with a rust removal degree of Sa3 is required to perform aluminum spraying and aluminum-magnesium alloy spraying directly on the substrate. Therefore, it has been regarded as a problem that a large amount of cost and time are required for blasting, and that the generated dust has an adverse effect on work safety and health and the environment. Therefore, a roughening treatment method that does not require the blasting treatment of Sa3 is being studied.

As a method that does not require the blasting treatment of Sa3, a method of applying a rough surface forming material can be mentioned. By applying this method, the grade of blasting can be reduced to Sa2 1/2 or less, and the construction time and cost required for blasting can be significantly reduced. For example, the adhesion can be ensured by applying a rough surface forming material composed of inorganic particles and a binder on the base material and forming an uneven resin layer on the surface of the base material.

However, in the method of applying the rough surface forming material, when the surface temperature of the base material immediately after thermal spraying exceeds 70 ° C., deterioration of the uneven resin layer due to heat and peeling due to stress accumulation in the uneven resin layer are likely to occur. Therefore, it is used only when the surface temperature of the base material immediately after thermal spraying is 70 ° C. or lower (normal temperature metal spraying).

As an example of normal temperature metal spraying, a method is known in which a pure zinc wire rod and a pure aluminum wire rod are simultaneously sprayed onto a base material to form a sprayed film of zinc-aluminum pseudoalloy (zinc: aluminum = 50: 50). Rough surface forming material can be applied.

On the other hand, an aluminum-magnesium alloy is known as a metal spraying material having excellent corrosion resistance to salt water, and the mass ratio of aluminum: magnesium is in the range of 90: 10 to 99.5: 0.5 from the viewpoint of corrosion resistance. Alloys are widely used. However, unlike the zinc-aluminum pseudoalloy, a room temperature metal spraying method has not been established, and a thermal spraying method is used in which the surface temperature of the substrate immediately after the spraying exceeds 70 ° C. Therefore, a rough surface forming material cannot be used in aluminum-magnesium alloy spraying, and Sa3 blasting is required. Therefore, the blasting grade can be reduced to Sa2 1/2 or less. A method for producing the above has been desired.

Japanese Unexamined Patent Publication No. 2-56424 Japanese Unexamined Patent Publication No. 3-28507

The aluminum-magnesium alloy, which initially has a magnesium content of 90: 10-99.5: 0.5, has a low magnesium content and is therefore considered for metal spraying such as melting point and latent heat of melting. The properties of the metal are close to those of pure aluminum (melting point 660 ° C., specific heat 917J / kg ° C., molten latent heat 397kJ / kg), and the spraying conditions are similar, and it is expected that the knowledge of pure aluminum will be utilized as it is.

By the way, pure magnesium has a melting point of 649 ° C., a specific heat of 1038 J / kg ° C., and a latent heat of melting of 368 kJ / kg (JWES Joining Welding Technology Q & A1000, Japan Welding Association, 2004 data).

However, in the aluminum-magnesium alloy, it was found that the wire rod did not melt under the same voltage conditions as pure aluminum spraying, and thermal spraying was not possible. Then, when the arc voltage was raised to melt the wire, the melting temperature became high and even the leader tip for introducing the wire was melted, and continuous spraying for more than 30 minutes could not be performed.

An object of the present invention is to find out the conditions for thermal spraying of an aluminum-magnesium alloy that enables continuous thermal spraying at room temperature, and to provide a laminate protected by the alloy.

The present inventors have found a condition in which such an aluminum-magnesium alloy (mass ratio 90: 10-99.5: 0.5) can be arc sprayed under reduced pressure, and have developed a method for obtaining a laminate containing a resin layer. I found it.

1. 1. A laminate having at least a base material, a resin layer containing particles having an average particle diameter of 10 to 150 μm, and an aluminum-magnesium alloy (mass ratio 90: 10 to 99.5: 0.5) sprayed layer in this order.
2. 2. This is a method for preparing a metal sprayed layer of an aluminum-magnesium alloy (mass ratio 90: 10-99.5: 0.5), in which the surface temperature of the base material immediately after spraying the alloy is above the atmospheric temperature and below 70 ° C. A method for producing a metal sprayed layer, which is characterized by thermal spraying.
3. 3. 2. The above-described 2 is characterized in that, in the metal spraying, a pure aluminum wire having the same diameter is sprayed with a metal based on a wire spraying speed at which the wire can be sprayed, and the metal is sprayed under a spraying condition which is a wire spraying speed slower than the feed rate. Method for producing a metal sprayed layer.
4. The method for producing a metal sprayed layer according to 2 or 3 above, wherein the metal is a wire rod having a diameter in the range of 0.8 to 2.0 mm in the metal spraying.

According to the present invention, even if the spraying apparatus is different, the aluminum-magnesium alloy can be sprayed by arc in reduced pressure by applying the conditions.

Hereinafter, embodiments of the present invention will be described in detail.

<Spraying conditions>
The present invention is characterized in that, first, the feed amount of the wire rod per unit time for arc spraying pure aluminum in reduced pressure is used as a reference, and the feed rate is slower than the feed rate.

Since the thermal spraying conditions are not necessarily the same for each thermal spraying device, it is possible to know the appropriate thermal spraying conditions for the aluminum-magnesium alloy by using the thermal spraying conditions for pure aluminum as a reference.

Generally, in order to melt a metal that does not melt, it is conceivable to increase the amount of heat input to a high temperature, and the thermal spraying conditions include adjustment of the feed rate and voltage of the wire rod. However, when the voltage is adjusted, the temperature of the molten metal naturally rises, and there are many restrictions on the thermal spraying device and the thermal spray base material, so that it is not possible to perform thermal spraying on the uneven resin layer instead of the blasting treatment.

On the other hand, in the method of making the feeding speed of the wire rod slower than the feeding speed of the pure aluminum wire rod, the temperature rise of the molten metal is suppressed, and thermal spraying to the uneven resin layer becomes possible. In the present invention, by thermal spraying under the above conditions, the surface temperature of the substrate immediately after thermal spraying can be set to a large temperature (meaning the temperature of the working place at the time of work) or more and 70 ° C. or less. Here, immediately after thermal spraying means within 10 seconds after thermal spraying on the base material. The normal temperature means a large temperature or more and 70 ° C or less.

In the present invention, it is presumed that the reason why the aluminum-magnesium alloy differs from that of pure aluminum in the behavior of thermal spraying conditions is that the thermal conductivity is different. Since the aluminum-magnesium alloy wire has a lower thermal conductivity than the aluminum wire, it is presumed that the aluminum-magnesium wire is less likely to transfer heat to the core than the aluminum wire when the same amount of heat is applied.

Therefore, as a result of increasing the amount of heat applied to the wire rod per unit volume by lowering the feed rate, it is considered that heat can be transferred to the core even in the aluminum-magnesium alloy. It is also known that magnesium segregates on the surface of aluminum-magnesium alloys, and it cannot be denied that this may be the cause.

Since the thermal spraying conditions of the aluminum-magnesium alloy differ depending on the thermal spraying device, it is rational to use the thermal spraying conditions of pure aluminum as a reference. The wire has a diameter of 0.8 to 2.0 mm, preferably 1.1 to 1.6 mm. The wire may be substantially circular, and if the cross-sectional areas are the same, the effect with the same diameter can be obtained.

The feeding speed of the wire rod is 1 to 18 m / min, the cathode and the anode are preferably fed at the same speed, and the arc voltage is preferably 15 to 45 V.
The spraying distance is preferably 100 to 300 mm, and the thickness of the sprayed layer is preferably 10 to 400 μm.

The feed rate of the wire is preferably 0.5 to 5 m / min when the pure aluminum is 8 m / min, and 1 to 10 m / min when the pure aluminum is 12 m / min. It can be appropriately determined depending on the thermal spraying model in the range of 5 to 95% of the feed rate of.

<Base material>
The base material used in the present invention refers to all base materials that can be sprayed, such as steel plates, non-ferrous metals, inorganic building materials, wood-based materials, plastics, ceramics, glass, and paper. For example, in addition to black-skinned steel sheets, dull steel sheets, polished steel sheets, stainless steel sheets, and cast steel sheets, surface-treated steel sheets such as tin plate, zinc-plated steel sheet, coated steel sheet, and laminated steel sheet are included as steel sheets, and aluminum, copper, etc. And their alloy sheets. As the inorganic building material, it can be applied to slate board, gypsum board, gypsum slag board, extruded cement board, GRC board, gypsum board, mortar board, lightweight bubble concrete board, rock wool board, glass board and ceramic board.

As the wood-based material, veneer plywood, particle board, hard board, tep board, decorative plywood and the like can be used in addition to natural wood boards such as beech, lauan and agathis. As the plastics, acrylic resin, polyvinyl chloride, polystyrene, ABS, nylon, polypropylene, phenol resin, glass fiber reinforced epoxy resin, polyphenyleoxide (PPO) and the like can be used.

As for the shape of the base material, if it has a three-dimensional pattern such as embossing or stucco pattern in addition to the flat plate, the metallic luster part of the thermal spraying layer and the concave part of the thermal spraying layer that appear when the convex part of the thermal spraying layer is polished ( A design appearance can be obtained by contrasting with the colored non-metallic luster portion of the colored paint film remaining on the non-polished portion).

Further, a base material obtained by combining the above materials, for example, a base material obtained by laminating paper, plastic, cloth or the like on a plastic foam and decorative plywood, or an inorganic base material is also included in the scope of the base material of the present invention.

<Resin layer>
Since the metal sprayed layer adheres to the base material by the anchor effect, when the base material is smooth, a rough surface forming material is applied to the surface of the base material to form a resin layer (hereinafter, also referred to as a concavo-convex resin layer). RSm (average spacing of irregularities) / Rz _JIS (10-point average roughness) ≤ 5.0, preferably RSm / Rz _JIS ≤ 3.5 of the layer.

The blasting process itself requires a great deal of skill, takes a long time, and the dust generated in a larger amount than the blasting has problems of environmental pollution as well as safety and hygiene of the work. , It is preferable to form an uneven resin layer.

A coating composition containing 25 to 400% by volume of particles having a particle diameter of 10 to 150 μm with respect to the resin is applied onto the base material at a ratio of 10 to 400 g / m ² , and RSm (average of unevenness) of the uneven resin layer is applied. Interval) / Rz _JIS (10-point average roughness) ≤ 5.0 can be obtained.

If the base material is an inorganic building material with strong alkalinity such as a slate plate, the metal sprayed layer may be discolored by the alkali. Therefore, before applying the rough surface forming material, epoxy resin, urethane resin, etc. are used to prevent alkalinity. It is also possible to paint the sealer of the above, and if the base material is a steel plate, electrical corrosion may occur depending on the type of sprayed layer, and in such a case, painting may be applied on the base material. preferable.

The resin layer of the present invention contains particles having an average particle diameter of 10 to 150 μm, and the particles include, for example, metals such as copper, nickel, aluminum, zinc, iron, and silicon, or alloys or oxides. Nitride, carbide and the like can be mentioned. Specific examples thereof include aluminum oxide, silicon oxide, iron oxide, silicon carbide, boron nitride and the like.

Further, depending on the solvent composition of the coating composition forming the resin layer, powders such as acrylic resin, styrene resin, epoxy resin and polyethylene may be used. These particles can be used as one kind or a mixture of two or more kinds. The use of silica sand, alumina, silicon carbide and the like is particularly preferable.

In the present invention, the average particle size of the particles is in the range of 10 to 150 μm, preferably 30 to 100 μm. The average particle size of the present invention is a volume particle size measured by a laser diffraction / scattering method.

In the present invention, the particles are set to 25 to 400% by volume [20 to 80% by volume of pigment volume (PVC)], preferably 65 to 150% by volume [pigment volume concentration (PVC)] with respect to the resin described later. It is used in the range of 40 to 60%].

The resin used in the present invention is not particularly limited as long as it has a certain degree of drying property, hardness, adhesion, water resistance and durability. Specific examples include thermoplastic acrylic resin, vinyl resin, rubber chloride, alkyd resin, which are one-component room temperature dry resins, unsaturated polyester resin, acrylic-urethane resin, polyester-urethane resin, and epoxy, which are two-component curable resins. Examples thereof include resins, melamine-alkyd resins, which are thermocurable resins, melamine-acrylic resins, melamine-polyester resins, acrylic resins, and acrylic-urethane resins. These can also be used as one kind or a mixture of two or more kinds.

Particularly preferred are epoxy resins (combined with a curing agent such as polyamide resin and amine adduct), acrylic-urethane resin, acrylic resin, etc., which are thermoplastic during thermal spraying and allow the sprayed metal particles to enter the coating and cure after thermal spraying. ..

As a component other than the resin, an organic solvent, water, or the like for dissolving or dispersing the resin is added to the coating composition of the present invention, if necessary. Additives such as dyes, pigments and dispersants, foaming inhibitors, and sagging inhibitors (thixotropic property imparting agents) can also be used in combination.

In the present invention, the coating composition is prepared by adding the resin and particles, if necessary, a solvent, a dispersion medium, various additives, etc., and mixing them by a usual dispersion and mixing method.

The coating composition of the present invention is applied onto a substrate by a usual method. In particular, the air spray method is preferable because discontinuous film formation is possible.

In the present invention, the coating amount of the coating composition needs to be 10 to 400 g / m ² . It is preferably 25 to 300 g / m ² , and particularly preferably 20 to 150 g / m ² .

In the present invention, the uneven resin layer after coating the composition is within the range of Rsm (average spacing of unevenness) / Rz _JIS (10-point average roughness) ≤ 5.0, preferably Rsm / Rz _JIS ≤ 3.5. It is necessary. In the present invention, Rsm and Rz _JIS are defined by JIS B-0601 (2001), and were measured by Mitutoyo Co., Ltd. surf test SJ-301 under an atmosphere of 23 ° C. and 50 RH%.

<Overcoat layer>
In the present invention, it is preferable to further apply at least one layer of synthetic resin paint on the sprayed metal layer for sealing to form an overcoat layer. It is known that the metal sprayed layer usually has irregularities with a surface roughness of about 100 μm in Rz _JIS , and has many pores (the pores often reach the underlying surface).

Therefore, in the present invention, in order to protect the metal sprayed layer, it is necessary to close the recesses and pores with a synthetic resin paint, and this significantly improves the protective effect of the metal sprayed layer. Further, depending on the usage conditions, it is possible to further perform surface coating.

The application of the synthetic resin coating material in the present invention includes not only covering the entire metal sprayed layer, but also filling and applying (sealing treatment) only the recesses and pores of the metal sprayed layer.

In the method of the present invention, the surface of the sprayed metal layer can be coated as it is, but in order to effectively seal the inside of the pores, a low-viscosity paint (seal) that can penetrate into the fine pores. It is preferable to coat the treatment material), and if necessary, perform intermediate coating and top coating. It is also a preferable method to polish the metal sprayed layer before painting in order to minimize the unevenness of the metal sprayed layer.

By such treatment, the convex portion on the surface of the sprayed metal layer is eliminated, the sprayed metal is not exposed on the surface after surface coating, the surface can be completely protected with a thinner coating film, and the appearance, gloss, etc. after coating are also improved. It can be greatly improved. As the polishing method, means usually used for polishing a metal surface such as polishing paper, polishing cloth, wire brush, belt sander, and sand grinder can be used.

As the synthetic resin coating material used in the method for producing the overcoat layer of the present invention, any known synthetic resin coating material generally available on the market can be used.

For example, bisphenol type epoxy resin, phenol novolac type epoxy resin, polyglycol type epoxy resin, ester type epoxy resin, etc. are used as color developing agents, or these are vegetatively modified or urethane modified, and amine adduct, polyamine. , Epoxy resin paint containing an amino-based curing agent such as polyamide resin or polyisocyanate curing agent; rubber chloride or a chloride rubber coating containing rosin, kumaron-inden resin, phenyl resin, petroleum resin, plasticizer, etc.; Vinyl chloride resin paint using a vinyl homopolymer or a copolymer of vinyl chloride and vinyl acetate, vinylidene chloride, etc. as a color developer; from monomers such as acrylic acid or methacrylic acid, these alkyl esters, styrene, vinyl toluene, etc. Acrylic resin coating using two or more selected copolymers as color developing agents; color developing agents obtained by condensing reaction products of polybasic acids such as phthalic acid, polyhydric alcohols such as glycerin, and fatty acids. Epoxy resin paint; polyester resin paint using the product obtained by the condensation reaction of polybasic acid and polyhydric alcohol as a color developer; polyisocyanate containing polyol components such as polyester polyol, polyether polyol, acrylic polyol as the main component Polyurethane resin coating (including epoxy modification) with epoxy as a curing agent; room temperature curing or heat-curing epoxy with a hydroxyl group-containing fluorine copolymer as the main component and polyisocyanate or melamine resin as the curing agent. Fluorescent resin paint using vinylidene resin as a color-developing agent; other silicone resin, silicone-modified epoxy resin, silicone-modified acrylic resin, etc. as a color-developing silicone resin paint; other phenol resin, melamine resin, etc. Can be mentioned.

If necessary, the synthetic resin coating material of the present invention may be added and mixed with various additives such as coloring pigments, extender pigments, dyes, other leveling agents, ultraviolet absorbers, and dispersion stabilizers. Further, the synthetic resin coating material used in the present invention may be any of solvent-based, water-soluble, water-dispersed, and solvent-free. Further, the synthetic resin coating material may be either a room temperature drying type or a forced drying (including heating) type.

(Experimental Example 1-1)
After grit blasting a 300 × 300 × 3.2 mm SS400 steel sheet with a degree of rust removal of Sa3, the aluminum-magnesium alloy layer is formed below using an arc spraying device A1 (SX-200 manufactured by Sunmeta Co., Ltd.) in reduced pressure. It was produced as follows.

First, thermal spraying was performed by the above apparatus using a pure zinc wire rod and a pure aluminum wire rod having a diameter of 1.3 mm (reference 1-1). The conditions under which continuous spraying was possible for 30 minutes were a feed rate of 8 m / min, an arc voltage of 15 V, an arc current of 120 A, an air pressure of 7 kg / cm ² , and an air flow rate of 1 m ³ / min (spraying distance of 200 mm).

Under the conditions of this standard 1-1, the results of thermal spraying of a 1.3 mm diameter pure zinc wire (Zn wire), pure aluminum wire (Al wire) and aluminum-magnesium alloy (95: 5) wire (AlMg alloy wire) are shown. It is shown in Table 1. The propriety of thermal spraying was judged according to the following criteria.
◯: Continuous thermal spraying possible for 30 minutes or more Δ: Thermal spraying possible, but continuous thermal spraying not possible for 30 minutes or more ×: Thermal spraying not possible The applicability to the uneven resin layer was also evaluated.
◯: Base material temperature immediately after thermal spraying is 70 ° C. or less ×: Base material temperature immediately after thermal spraying exceeds 70 ° C. (Peeling may occur due to deterioration of the uneven resin layer due to heat or stress accumulation in the uneven resin layer. Because there is, it is evaluated as not applicable)

As shown in Table 1, when the feed rate of the wire was slowed with respect to the spraying conditions of the pure zinc wire and the pure aluminum wire, spraying at room temperature became possible. It should be noted that simply increasing the voltage did not enable thermal spraying at room temperature, and the effect of the feeding speed of the wire rod became clear.

(Experimental Example 1-2)
Under the conditions of Experimental Example 1-1, aluminum-magnesium alloy (95: 5) wires having different diameters were sprayed. The results are shown in Table 2.

When a wire rod with a diameter of 2.0 mm is sprayed under the conditions of Reference 1-1 and Example 1, the amount of heat per unit volume of the wire rod is small and the wire rod cannot be melted. Therefore, as shown in Table 2, the voltage is increased to 17 V for thermal spraying. went. As a result, similar to the tendency of the thermal spraying condition of the 1.3 mm diameter wire, when the feed rate of the wire is slower than the thermal spraying condition of the pure zinc wire and the pure aluminum wire in the aluminum-magnesium alloy wire, immediately after the thermal spraying. The surface temperature of the base material became normal temperature, and it became possible to spray on the uneven resin layer.

(Experimental Example 2-1)
In Experimental Example 2-1 the following resin layer was provided after performing a grit blast treatment with Sa2 1/2 instead of the rust removal degree Sa3 of Experimental Example 1.
Epoxy resin (Epoxy 4051 Dainippon Ink and Chemicals Co., Ltd. epoxy equivalent 950) was dissolved by adding 80 g of xylene, methyl ethyl ketone 60 g, and butanol 25 g, and 10 g of polyamide resin (Epicure 892 Ceranies active hydrogen equivalent 133) was added to prepare the mixture. 275 g of epoxy polyamide resin B with a heating residue of 40% (resin solid content volume 100 cm ³ ) and silicon carbide with an average particle diameter of 48 μm (green silicon carbide CG320 manufactured by Nagoya Abrasive Equipment Industry, specific gravity 3.16) 221 g (particle volume 70 cm ³ , PVC41) %) Was sufficiently stirred to prepare a resin composition A.

Next, 60 g / m ^{2 of} this resin composition A was applied to a 300 × 300 × 3.2 mm SS400 steel sheet by air spray, the average spacing (RSm) of the irregularities on the surface was 280 μm, and the ten-point average roughness (Rz _JIS). ) Was set to 120 μm. At this time, the surface roughness (RSm / Rz _JIS ) is 2.3.

The concave-convex resin layer was sprayed using an arc spraying device A2 (AS-400 manufactured by Daihen Corporation) under reduced pressure, and a pure zinc wire / pure aluminum wire having a diameter of 1.3 mm was used in the same manner as in Experimental Example 1. (Criteria 2-1).
Under the conditions of this standard 2-1 the pure zinc wire / pure aluminum wire and the aluminum-magnesium alloy (95: 5) wire having a diameter of 1.3 mm were sprayed. The results are shown in Table 3.

As shown in Table 3, when the feeding speed of the wire rod was slowed with respect to the thermal spraying conditions of pure zinc and pure aluminum, thermal spraying to the resin layer at room temperature became possible. It should be noted that simply increasing the voltage did not enable thermal spraying, and the effect of the feeding speed of the wire rod became clear.

(Experimental Example 2-2)
Under the conditions of Experimental Example 2-1 the aluminum-magnesium alloy (95: 5) wires having different diameters were sprayed. The results are shown in Table 4.

When a wire rod with a diameter of 2.0 mm is sprayed under the conditions of Reference 2-1 and Example 3, the amount of heat per unit volume of the wire rod is small and the wire rod cannot be melted. Therefore, as shown in Table 4, the voltage is increased to 30 V for thermal spraying. Was done. As a result, similar to the tendency of the thermal spraying condition of the 1.3 mm diameter wire rod, when the feed rate of the wire rod is slowed with respect to the thermal spraying condition of pure zinc and pure aluminum in the aluminum-magnesium alloy wire rod, the uneven resin layer at room temperature It is now possible to spray on.

Claims (4)

A laminate having at least a base material, a resin layer containing particles having an average particle diameter of 10 to 150 μm, and an aluminum-magnesium alloy (mass ratio 90: 10 to 99.5: 0.5) sprayed layer in this order. This is a method for preparing a metal sprayed layer of an aluminum-magnesium alloy (mass ratio 90: 10-99.5: 0.5), in which the surface temperature of the base material immediately after spraying the alloy is above the atmospheric temperature and below 70 ° C. A method for producing a metal sprayed layer, which is characterized by thermal spraying. The second aspect of claim 2, wherein in the metal spraying, a pure aluminum wire having the same diameter is sprayed with a metal based on a wire spraying speed at which the wire can be sprayed, and the metal spraying conditions are a wire spraying speed slower than the feed rate. How to make a metal sprayed layer. The method for producing a metal sprayed layer according to claim 2 or 3, wherein in the metal spraying, the metal is a wire rod having a diameter in the range of 0.8 to 2.0 mm.