JP2006052382A - Treating liquid for improving formability and workability of metal plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a treating liquid for improving formability and workability in which excellent lubricating effect is developed by applying it onto a metal plate, particularly the metal plate having a slightly workable property, e.g. a magnesium alloy plate. <P>SOLUTION: The treating liquid for improving formability and workability of the metal plate is obtained by including one or more kinds of organic resins selected from a water-soluble urethane resin, a water-soluble polyester resin, a water-soluble acrylic resin, a water-soluble epoxy resin, etc. or adding a silane coupling agent, a colloidal silica, a lubricant, etc., to the one or more kinds of organic resins. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a metal plate forming processability improving treatment liquid used for improving the forming processability of metal plates, particularly difficult-to-work metal plates such as magnesium alloy plates.

  Portable electronic devices such as mobile communication devices and notebook computers are always required to be lighter, and a magnesium alloy, which is a lightweight metal, is used as an outer case for these devices. However, the magnesium alloy has poor workability, and it is extremely difficult to obtain a container with a low drawing ratio that is drawn with a high drawing ratio. In order to draw such a difficult-to-work magnesium alloy, a draw forming process is performed by heating the die, punch, and wrinkle pressing member of the draw forming apparatus to about 150 to 400 ° C. (for example, Patent Document 1). See), heating the die, punch, and blank holder, and heating magnesium to the recrystallization temperature range through these forming tools, and the heating recrystallizes the magnesium and softens it, thereby inducing an annealing effect that tends to cause plastic deformation. A magnesium alloy hard case manufacturing method (for example, see Patent Document 2) in which a magnesium blank is hot-drawn in a box shape while the magnesium blank is heated, or a surface of at least one of a punch and a die A plate made of pure magnesium, pure aluminum, resin, etc., which is softer than the magnesium plate, is (For example, see Patent Document 3), a method in which a tetrafluoroethylene sheet is installed as a heat insulating material on the upper and lower surfaces of a heated magnesium thin plate, and press molding is performed at a high temperature (for example, see Patent Document 4). ing. As shown in these proposals, when a forming process such as drawing is performed on a magnesium alloy, it is essential to heat it to a recrystallization temperature range.

  It has also been proposed to use a lubricant to facilitate processing. For example, a method of forming an ultra-hard film such as titanium nitride or diamond-like carbon on the surface of a press mold by a coating process (for example, see Patent Document 5), biodegradable oils and fats, rust preventive / lubricant, pole There has been proposed a method (for example, see Patent Document 6) of forming using a plastic working oil for magnesium alloy or aluminum alloy containing a pressure additive, and further an organic zinc compound and an organic molybdenum compound. However, all of these methods are used when forming by cold working, and an effective lubricating effect cannot be obtained when forming at a working temperature exceeding 200 ° C. as in the above example.

  Prior art documents relating to the present invention include the following.

JP 2003-290843 A JP 2002-254115 A Japanese Patent Laid-Open No. 2001-300643 Japanese Patent Laid-Open No. 06-328155 JP 2003-154418 A JP 2003-105364 A

  An object of the present invention is to provide a metal plate forming processability improving treatment liquid which is applied to a metal plate, particularly a difficult-to-work metal plate such as a magnesium alloy plate, and dried to form a film, and exhibits an excellent lubricating effect. And

In order to achieve the object of the present invention, the metal plate molding processability improving treatment liquid of the present invention is a water-soluble urethane resin, a water-soluble polyester resin, a water-soluble acrylic resin, or a water-soluble epoxy resin, or 2 A metal plate forming processability improving treatment liquid (claim 1) comprising at least seeds,
In the above processing solution for improving metal plate forming processability (claim 1), the processing solution for improving metal plate forming processability is one or more of silane coupling agent, colloidal silica, and lubricant. (Claim 2) characterized in that, in the treatment liquid for improving metal plate molding processability of the above (Claim 1 or 2), the treatment liquid for improving metal plate molding processability is a heat resistance imparting agent. (Claim 3), and in the treatment liquid for improving metal plate moldability of (Claim 3), the heat resistance imparting agent is a siloxane compound (Claim 4). It is characterized by.

  The metal plate forming processability improving treatment liquid of the present invention is applied to a metal plate surface, particularly a difficult-to-work magnesium alloy plate, and is coated and dried to form a lubricating film. It is possible to manufacture difficult-to-process magnesium alloy sheets in drawn containers and to roll them into thin sheets without causing cracks. When an imparting agent is contained, a magnesium alloy plate, which is a difficult-to-work metal, is processed particularly in a warm working temperature range of 200 to 350 ° C., and an excellent lubricating effect is exhibited without decomposition of the film. It becomes possible to form into a magnesium alloy container with a high degree of processing with a ratio of 3.5 or less, or to roll at a higher rolling reduction by a single rolling operation.

  Hereinafter, the present invention will be described in detail.

  The resin constituting the main component of the processing solution for improving metal plate moldability of the present invention is preferably a water-soluble or water-dispersible resin, water-soluble urethane resin, water-soluble polyester resin, water-soluble acrylic resin, water-soluble It is preferable that it is either of an epoxy resin. These organic resins may be used alone or in combination of two or more.

  These organic resins may be used by coating and drying the resin alone on the surface of the metal plate to form a film, but in order to improve the moldability and corrosion resistance of the metal plate, the organic resin may contain the following substances: May be used. By including a silane coupling agent, the adhesion of the organic resin film to the metal plate, particularly the adhesion during molding, is significantly improved. The silane coupling agent is preferably contained in the organic resin film at 5% by weight or less, more preferably 1% by weight or less. Even if the content exceeds 5% by weight, the effect of improving the adhesion is saturated, which is not economically advantageous.

  Moreover, by including colloidal silica, the hardness of the organic resin film is improved, the scratch resistance of the metal plate is improved, and the corrosion resistance is also improved. The colloidal silica is preferably contained in the organic resin film at 50% by weight or less. If the content exceeds 50% by weight, the organic resin film becomes too hard, the workability of the organic resin film deteriorates, and cracks are likely to occur in the organic resin film during molding.

  Furthermore, by including a lubricant, the moldability of the metal plate for molding processing on which the organic resin film is formed is improved. Lubricants include higher fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, calcium salts of these higher fatty acids, aluminum salts, zinc salts, barium salts, magnesium salts, higher fatty acid esters thereof, polyethylene wax, Polyolefin wax such as polypropylene wax, fluorine-based wax such as polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, and polyvinyl fluoride, inorganic powder such as graphite, molybdenum disulfide, and boron nitride can be used. . These lubricants are preferably contained in the organic resin film at 20% by weight or less. When the content exceeds 20% by weight, the adhesion deteriorates even during the molding process of the organic resin film on the metal plate. Said silane coupling agent, colloidal silica, and lubricant may be contained individually by 1 type in the organic resin film, respectively, but 2 or more types may contain them.

  The organic resin obtained as described above is applied to and dried on at least one side, preferably both sides, of the metal plate to form an organic resin film. The thickness of the organic resin film is preferably 0.1 to 30 μm, more preferably 1 to 10 μm after drying.

  The metal plate forming processability improving treatment liquid of the present invention can be applied to a metal plate or alloy plate that can be cold-rolled, but is particularly difficult to process and has a low recrystallization temperature. It can be suitably used for magnesium and magnesium alloys that can be processed. Moreover, it can be used suitably also for an aluminum alloy. When drawing or rolling a plate made of magnesium or a magnesium alloy, drawing work is improved by heating and drawing in a temperature range of 350 ° C. or less, preferably 200 to 350 ° C. It can be formed into a drawn container having a side wall length larger than the diameter, or ear cracks are less likely to occur during rolling, and the rolling reduction in one rolling operation can be increased. However, when drawing or rolling in a temperature range exceeding 200 ° C., the organic resin film decomposes and discolors or cracks occur in the film, which deteriorates the appearance and makes it difficult to improve the drawing ratio and reduction ratio. Become. Therefore, by further adding a heat resistance imparting agent to the organic resin film, the organic resin film can be stably drawn without causing discoloration or cracking in the high temperature processing temperature range of 200 to 350 ° C. or less. Or rolling.

  As the heat resistance imparting agent, it is preferable to use a heat resistant resin such as polyimide or a siloxane compound. Examples of the siloxane compound include polymers and monomers of organosiloxanes such as dimethylsiloxane, diethylsiloxane, methylethylsiloxane, diphenylsiloxane, and methylphenylsiloxane, or polyalkylene oxide groups, hydroxyl groups, amide groups, and carboxyl groups in these organosiloxane molecules. , One having at least one substituent of at least one of a sulfone group and an amino group is preferably used. These heat resistance imparting agents are preferably contained in the organic resin film in an amount of 5 to 80% by weight, and more preferably 10 to 60% by weight. Thus, by including a heat resistance imparting agent in the organic resin film, for example, when a magnesium alloy plate is used as the metal plate, it is heated to a warm working temperature range of 200 to 350 ° C., and the drawing ratio is 3.5. With a drawing ratio as high as possible, it is possible to draw a magnesium alloy container having a longer side wall length than the bottom diameter. The heat resistance imparting agent may be contained alone in the organic resin, but may be contained in combination with one or more of the above silane coupling agent, colloidal silica, and lubricant. Good.

  It is also possible to apply a coating to an organic resin film formed by applying the metal plate molding processability improving liquid of the present invention to a metal plate and drying it. The painted plate may be rolled or drawn. In addition, after forming into a container or thin plate, the organic resin film is dissolved and removed using an alkali solution, or after removing the organic resin film using a shot blasting method in which abrasive particles are sprayed on the surface, anodizing treatment, plating, etc. A surface treatment can also be applied.

  Hereinafter, the present invention will be described in detail with reference to examples.

(Creation of processing liquid for improving metal plate forming processability)
A silane coupling agent, colloidal silica, a lubricant, and a heat resistance imparting agent were contained in the water-soluble resin in the amounts shown in Table 1, and metal plate molding processability improving liquids shown in Sample Nos. 1 to 13 were prepared.

(Making magnesium alloy sheets for forming)
Next, the processing solutions for improving the metal plate molding processability of Sample Nos. 1 to 13 were added to both surfaces of a 0.725 mm thick magnesium alloy plate having the following alloy components, and the respective additives were in the resin film in a dried state. In order to obtain the content shown in Table 1 and to dry the resin film to the thickness shown in Table 1, it was applied and dried using a bar coater, and the molding process for the test shown in Table 1 was performed. Magnesium alloy plates (sample numbers 1 to 13) were prepared.
<Alloy components>
Al: 3.0 wt%, Zn: 1.1 wt%, Mn: 0.35 wt%, balance: Mg and inevitable impurity elements <Average crystal grain size>
8μm

(Evaluation of workability of magnesium alloy sheet for forming)
As an evaluation of the workability of the magnesium alloy sheet for forming, drawing was performed under the following conditions to obtain a limit drawing ratio.
<Punch shoulder R>
4mm
<Punch temperature>
Room temperature <Dice temperature>
50 ° C, 150 ° C, 200 ° C, 250 ° C, 300 ° C, 350 ° C
<Blank holder temperature>
50 ° C, 150 ° C, 200 ° C, 250 ° C, 300 ° C, 350 ° C
<Aperture speed>
1mm / sec <Lubricant>
Molybdenum disulfide is used as a solid lubricant for some samples

  For comparison, the magnesium alloy plate (Sample No. 14) and a magnesium alloy plate with a 50 μm thick tetrafluoroethylene film attached on both sides (Sample No. 15) were drawn under the same conditions, The aperture ratio was determined. In the case of a magnesium alloy plate not attached with a tetrafluoroethylene film, the workability at room temperature is extremely inferior, and it is difficult to draw even using a lubricating oil or a solid lubricant. Drawing was performed only when the holder temperature was 200 ° C. or higher. In the case of a magnesium alloy plate with a tetrafluoroethylene film attached, if the die temperature and the blank holder temperature are 350 ° C., the tetrafluoroethylene film is severely damaged and difficult to be drawn. Drawing was performed only when the temperature was 150 to 300 ° C.

(Evaluation of appearance of organic resin film)
Further, the appearance of the organic resin film on the surface of the magnesium alloy container after the forming process was visually observed and evaluated according to the following criteria.
A: Discoloration or damage of the film is not observed.
○: Slight discoloration of the film is observed, but no damage is observed.
Δ: Discoloration and damage of the film are observed.
X: Severe damage to the film and wrinkles that are practically problematic on the surface of the molded container are observed.
These results are shown in Tables 2-4.

  As shown in Tables 2 to 4, the magnesium alloy plate for forming formed by coating with the organic resin film formed by applying and drying the metal plate forming processability improving liquid of the present invention has excellent drawing workability. Have. In addition, when an organic resin contains a heat resistance imparting agent, it can be drawn at a high temperature up to 350 ° C., and when drawn at such a high temperature, the drawing ratio is as high as 3.5. It is possible to draw the magnesium alloy container at a degree.

  When the surface of a metal plate, particularly a difficult-to-work magnesium alloy plate, is coated with the treatment solution for improving the metal plate moldability of the present invention, dried, and formed into a lubricating film, the degree of processing is high. Thus, it becomes possible to manufacture a difficult-to-process magnesium alloy plate or the like into a squeezed container or to roll it into a thin plate without causing an ear crack. In particular, when a heat resistance imparting agent such as a siloxane compound is included in the processing solution for improving metal plate forming processability, a magnesium alloy plate which is a difficult-to-work metal is processed in a warm processing temperature range of 200 to 350 ° C. In this case, an excellent lubricating effect is exhibited without decomposition of the film, and the magnesium alloy container can be formed and processed at a high processing degree with a drawing ratio of 3.5 or less. Moreover, when rolling, it can roll by raising a rolling reduction rate by one rolling operation.

Claims (4)

  A treatment liquid for improving metal plate molding processability, comprising one or more of a water-soluble urethane resin, a water-soluble polyester resin, a water-soluble acrylic resin, and a water-soluble epoxy resin.   2. The metal plate molding according to claim 1, wherein the metal plate molding processability improving treatment liquid contains any one or more of a silane coupling agent, colloidal silica, and a lubricant. Treatment liquid for improving workability.   The metal plate forming processability improving treatment solution according to claim 1 or 2, wherein the metal plate forming processability improving treatment liquid contains a heat resistance imparting agent. 4. The metal plate forming processability improving treatment solution according to claim 3, wherein the heat resistance imparting agent is a siloxane compound.