JPH03203636A - Damping steel plate and preparation thereof - Google Patents

Abstract

PURPOSE:To enhance resistance weldability, heat resistance and damping capacity by interposing a damping metal layer having particles composed of a high m.p. material scattered thereon as an interval securing material between steel plates in a laminated state. CONSTITUTION:At first, a flame spraying material prepared by mixing a damping metal powder with a powder of a material having an m.p. higher than that of said metal powder is applied to the surfaces of steel plates by flame spraying. At this time, when a flame spraying condition is set so that the damping metal can be properly subjected to flame spraying, the powder particles of the damping metal collide with the surfaces of the steel plates in a perfectly molten state and the liquid droplets of the damping metal 1 are flattened to be laminated to and accumulated on the surfaces of the steel plates 2 while the high m.p. material 3 is bonded as solid particles because it is not melted under the flame spraying condition. Subsequently, the steel plates each having the mixed layer of the damping metal and the high m.p. material formed to the surface thereof by flame spraying are superposed through the flame spraying layers thereof and heated to temp. directly above the m.p. of the damping metal 1 under pressure. The damping metal is melted and the steel plates 2, 2 are integrally bonded but the high m.p. material 3 remains in a solid phase particulate state.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a vibration-damping steel plate with excellent vibration-damping properties having a sufficiently thick damping metal layer, and a method for manufacturing the same.

<Prior art and its issues> In recent years, mechanical bags have been used for automobiles, OA equipment, home appliances, etc. ! The demand for quieter products is increasing day by day, and as a result, the demand for vibration-damping steel plates with excellent sound insulation properties is rapidly increasing.

By the way, "one in which a resin layer is laminated and interposed between two steel plates" is conventionally known as one of the laminated vibration damping steel plates having a relatively high damping ability. This resin composite damping steel plate was easy to manufacture and had excellent sound insulation properties, but on the other hand,
Since the steel plates that make up the front and back surfaces are insulated by a resin layer, it has been pointed out that resistance welding cannot be performed directly as is, and that there is a limit to the operating temperature due to poor heat resistance. In this respect, the applications had to be limited. However, in order to impart resistance weldability to resin composite damping steel sheets, attempts have been made to mix metal powder into the laminated resin layer to ensure conductivity, but no improvement measures have been taken to address the poor heat resistance. I couldn't find it.

Therefore, for applications that require heat resistance and resistance weldability,
A damping steel plate was used in which a "layer of metal with damping properties" was laminated and interposed as an intermediate layer between two steel plates, but this damping steel plate with a layer of damping metal was difficult to manufacture. The current situation is that the field of application has been sluggish because of the cost disadvantage.

Therefore, in order to manufacture a damping steel plate laminated with the above-mentioned damping metals in a simple process and at low cost, the damping metal is thermally sprayed between two heated steel strips (steel plates), and immediately after that, the damping metal is heated. A method of pressure bonding using rolls was proposed (Japanese Patent Application Laid-Open No. 1999-1-1).
27184), in this method, the intermediate layer metal (damping metal) is in a molten state and is pressurized with a roll to integrate it, so the thickness of the intermediate layer inevitably becomes small. There was a problem that the damping ability of the damping steel plate was not sufficient.

Separately, after scattering copper powder between two steel plates, it is annealed while being pressed at a predetermined pressure to integrate the steel plate and copper powder through diffusion bonding. A method of manufacturing damping steel plates with gaps between them has also been proposed ("Tetsu to Hagane J vol. 73 No. 13 (September 1987).
Month), p. 360). However, the damping effect of damping steel sheets manufactured using this method is due to the "friction that occurs in the gaps formed between the steel sheets," so the above-mentioned "resin composite damping steel sheets" and "damping It was difficult to do anything about the inferior vibration damping ability compared to "vibration damping steel plates made of laminated metal."

Therefore, the purpose of the present invention is to easily and inexpensively produce a vibration-damping steel plate that not only has good resistance weldability and heat resistance, but also has a sufficiently high damping ability. The aim was to establish a means that could be provided in the future.

Means for Solving the Problems> As a result of intensive research from various viewpoints in order to achieve the above object, the present inventors have developed the following method: When manufacturing vibration-damping steel plates by pressing and integrating steel plates sandwiched together while heating them to a temperature just above the melting point of the vibration-damping metal, the thermal spraying material “
By forming a thermal spray layer using a mixture of the vibration-damping metal to be sprayed and powder of a material with a higher melting point than the vibration-damping metal, it is possible to form a solid phase when the laminated steel sheets are integrated by heating and pressurizing. The high melting point material particles dotted in the sprayed layer play the role of supports that maintain the distance between the steel plate surfaces, and the thickness of the intermediate layer (damping gold JX with high melting point material particles dotted therein) Because it acts to prevent particles from becoming smaller than their particle size,
As a result, a damping steel plate with a damping metal layer (intermediate layer) thickness sufficient to exhibit the desired damping properties can be easily and stably obtained." Ta.

The present invention has been made based on the above-mentioned findings, etc., and is based on the above-mentioned findings. It is characterized by having sufficient resistance weldability, heat resistance, and excellent vibration damping ability by adopting a structure that is The steel plates (including copper strips) that have been thermally sprayed with layers, or the steel plates that have not been thermally sprayed are stacked on top of each other with the thermally sprayed layer on the inside,
By heating these materials under pressure to a temperature just above the melting point of the damping metal and integrating them, a damping steel plate with sufficient resistance weldability, heat resistance, and excellent damping ability can be easily and stably produced. It is also characterized by the fact that it can be easily manufactured.

Here, the “damping metal” to be applied, for example, Zn.
-The type of metal does not matter as long as it has vibration damping properties such as A1 alloy, PB, PB gold alloy MnCu alloy, etc., but in consideration of manufacturability, it is preferable to use a metal with a lower melting point. .

In addition, the "high melting point material" to be interspersed in the vibration damping metal layer is one that has a higher melting point than the applied vibration damping metal and has sufficient strength at the bonding temperature (laminated integration temperature).
For example, in metals, Cr steel + Cr Mo steel.

Stainless steel, Ni-based alloys, Co-based alloys, etc. can be used, and good results can also be obtained by applying ceramics (oxides, carbides, nitrides, etc.). However, the particle size of the high melting point material powder mixed into the thermal spray material is determined by the vibration damping metal layer (
In order to determine the thickness of the intermediate layer (intermediate layer), the larger the particle size is, the more preferable it is from the viewpoint of vibration damping ability, and it is preferable to use particles of 401XIf1 or more if possible.

In this case, the mixing ratio of the damping metal and the high-melting point material powder in the sprayed material is such that if the proportion of the high-melting point material powder is too small, the distance between the high-melting point material particles scattered in the sprayed layer will become long and The effect of the two plates is not sufficiently exerted, and the steel plate surfaces become too close to each other during pressurization and integration, reducing the effect of ensuring the thickness of the intermediate layer. Therefore, the vibration damping steel plate obtained only has inferior vibration damping ability. On the other hand, if the proportion of the high melting point material powder is too large, the "occupancy rate of the damping metal" in the intermediate layer of the obtained damping steel plate decreases, and the damping ability deteriorates. Therefore, the mixing ratio of the damping metal and the high melting point material powder in the thermal spray material (substantially the same as the ratio of the damping metal and the high melting point material powder in the intermediate layer of the resulting damping steel sheet) is desirable. is a high melting point material in volume ratio: 10 to 50
It is best to adjust it within a range of %.

As a method for spraying the thermal spray material onto the steel plate surface, gas spraying using powder as a raw material, plasma spraying, explosive spraying, or the like can be employed.

When joining steel plates stacked together with a thermal spray layer in between, a method is adopted in which the stacked materials are heated to just above the melting point of the damping metal applied while pressurizing them. It is better to apply the "honto-press method" or the "rolling method using heated rolls." In this case, the appropriate heating temperature is about [the melting point of the damping metal + 200°C], and it is desirable to keep the pressing force to a level that does not deform the high melting point material.
It is determined appropriately depending on the volume ratio of the high melting point material, etc.

<Function> In manufacturing the damping steel plate according to the present invention, first, the skin steel plate (copper strip) surface is sprayed with a mixture of damping metal powder and powder of a material with a higher melting point than the skin steel plate (copper strip). Spray the material.

At this time, if the spraying conditions are set so that the vibration-damping metal can be properly sprayed, the powder particles of the vibration-damping metal will collide with the steel plate surface in a completely molten state, so the vibration-damping metal powder particles will collide with the steel plate surface in a completely molten state. The droplets of the high melting point material (1) are flattened and stacked and deposited on the surface of the steel plate (2), while the high melting point material (3) does not melt under these conditions and therefore adheres in the form of solid particles.

Next, the steel plate whose surface has been thermally sprayed with a mixed layer of a damping metal and a high-melting point material is overlapped with its thermally sprayed surfaces as shown in FIG. 1(b) (in this case, one side is thermally sprayed). (It may be a steel plate without pressure), and is heated to just above the melting point of the damping metal (1) without being pressurized. Therefore, the damping metal melts and the copper plates (21, f2) are joined and integrated, but the high melting point material (3) remains in a solid phase particle state [FIG. 1(C)]. Therefore, the thickness of the intermediate layer (layer mainly composed of vibration-damping metal) is determined by the height (particle diameter) of the particles attached to the high melting point material, and cannot be made thinner than that. In other words, the thickness of the intermediate layer can be controlled arbitrarily by the particle size of the high-melting point material powder, and damping steel plates with various damping abilities can be freely and stably manufactured by selecting the particle size of the high-melting point material powder. be.

Next, the present invention will be explained in more detail with reference to Examples.

<Example> A cold-rolled steel strip (JISS PCC equivalent material) with a thickness of 1.6 fl was prepared, and as shown in FIG. Zn-20@t
After spraying a mixed powder spraying material of %M alloy powder, U, and O3 powder, two copper strips (4) are placed on top of each other with the sprayed layer sandwiched in between, and then this is heated in a heating furnace (6) in a predetermined position. After heating to a certain temperature, they were pressed and joined using rolling rolls (7) to produce a laminated steel plate.

The thermal spraying conditions and bonding conditions at this time were as follows.

Sansakusha ZnZn-20i, %M alloy powder (particle size: 10-44m
, melting point: 480°C) and Alz O3 powder (particle size: 44~
105gI+, melting point: 2050℃) at various mixing ratios (
Mixed powder mixed in volume ratio).

Yatamajo line Spraying method: Plasma spraying.

Plasma current: 400A.

Spraying distance: 300B.

Plasma gas (flow rate): Ar (50N/win
).

Torch nozzle diameter: 6m.

Moving speed of belt: 20m/in.

Sprayed film thickness: 150m.

Ikejo-mori Heating temperature: 520°C.

Threading speed: 20 m/ll1n.

Next, a test piece ((1.6m+1
, 6 m) thick x 50 x width x 100 m long) was cut out and its damping characteristics were evaluated. In addition, for evaluation of vibration damping characteristics,
As shown in Figure 3, the above test piece (8) was suspended with a string,
Steel ball (9) also suspended from a string (diameter: 38 m).

(Weight: 235 g) were collided at an angle of 45° as shown in Figure 3(b), and the "maximum instantaneous value of impact sound" at that time was measured in impulse mode.

The results of this evaluation are shown in FIG.

As is clear from the results shown in Figure 4, the damping metal J! (Zn-20χA1 alloy layer) has high melting point material particles (
It can be seen that the damping ability of the damping steel sheet according to the present invention, in which the Zn-20χM alloy layer is dotted with ARz O3 particles, is significantly improved compared to the case where the damping steel sheet does not contain AI1203), that is, the conventional damping steel sheet. From FIG. 4, it is clear that in order to ensure particularly stable damping characteristics, the proportion of high melting point material particles interspersed in the damping metal layer should be 10 to 50 vol. It can also be seen that it is desirable to adjust it to about %.

<Summary of Effects> As explained above, according to the present invention, since the conductive vibration-damping metal layer is provided, resistance weldability and heat resistance are good, and the vibration-damping metal layer has a sufficient thickness. This brings about extremely useful effects industrially, such as making it possible to provide a laminated vibration damping steel plate that exhibits excellent damping ability at a low cost.

[Brief explanation of drawings]

Figure 1 (al to Figure 1 (C1) are conceptual diagrams sequentially explaining the manufacturing process of the damping steel plate according to the present invention. Figure 2 shows the manufacturing method of the damping steel plate adopted in the example. FIG. 3(a) and FIG. 3(bl) are conceptual diagrams illustrating a method for evaluating the damping characteristics of a damping steel plate. FIG. It is a graph showing the vibration damping characteristic evaluation results of the vibration damping steel plate. In the drawing, 1... damping metal. 3... high melting point material. 5... thermal spraying torch. 7... processing. Pressure port. 9... Steel ball. 2... Steel plate. 4... Steel strip. 6... Heating furnace. 8... Test piece. Figure 1

Claims (2)

[Claims] (1) A vibration-damping steel plate characterized in that vibration-damping metal layers dotted with high-melting point material particles as a spacing material are laminated and interposed between the steel plates. (2) Steel plates whose surfaces have been thermally sprayed with a mixed layer of vibration-damping metal and high-melting point material powder, or the steel plates and a steel plate which has not been thermally sprayed, are placed one on top of the other with the thermally sprayed layer on the inside, and while pressurizing them, A method for manufacturing a vibration-damping steel plate, characterized in that the damping metal is heated to a temperature just above the melting point of the vibration-damping metal to be integrated.