JP2002285315A - Structural base material using volcanic ash and method of producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a ceramic tile-like structural base material having sufficiently high finished dimension accuracy, which is obtained by utilizing volcanic ash and to provide a method for producing the same. SOLUTION: The structural base material is composed of a base material 11, an underlaying layer 12 and a thermally sprayed layer 15 of the volcanic ash. As the base material 11, a metal, a ceramic, concrete, a plastic, or the like, is used. The underlaying layer 12 is formed by gas thermal spraying or water plasma thermal spraying using a metal or a ceramic. The thermally sprayed layer 15 of the volcanic ash is formed by water plasma thermal spraying of the volcanic ash or a material containing the volcanic ash as a main component. It is preferable that the surface to be treated of the base material 1 is previously subjected to blasting and further the surface of the thermally sprayed layer 15 of the volcanic ash is subjected to melting treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structural material using volcanic ash and a method for producing the same.

[0002]

BACKGROUND OF THE INVENTION As one of the world's leading volcanic countries, Japan has suffered from active volcanic activity, not to mention Miyakejima and Usuyama. In particular, it is well known that volcanic ash emitted during volcanic activity is a large amount, a fine powder, and contains harmful components such as sulfur, thus causing a great deal of damage to livestock and agricultural products.

[0003] There is almost no effective use of such volcanic ash, and at present, most of the ash is disposed of in a place having relatively little influence on the environment. However, since harmful components are contained in the fine powder, serious problems such as environmental destruction sometimes occur at the time of transportation and landfill.

[0004]

2. Description of the Related Art On the other hand, there have been provided ceramic tiles made of a mixture of earth and stone powder and clay, and these are fired at a high temperature of about 800 to 1300 ° C. However, ceramic tiles need to be fired at high temperatures, so large-sized products and special structures such as circular ones are subject to thermal deformation, failing to maintain the strict accuracy of finished dimensions, making them difficult to use as building materials. Had a point.

Accordingly, an object of the present invention is to provide a ceramic tile-like structural material and a method for producing the same, which are capable of ensuring the accuracy of finished dimensions as part of the effective use of volcanic ash.

[0006]

In order to achieve the above objects, the structural material according to the present invention comprises a base material such as metal, ceramic, concrete, plastic or the like, and a main component comprising volcanic ash sprayed thereon. And a sprayed volcanic ash layer. One or two underlayers may be interposed between the base material and the volcanic ash sprayed layer. The underlayer is preferably a gas sprayed layer and / or a water plasma sprayed layer mainly composed of a metal such as a NiAl alloy or a ceramic such as a zirconia ceramic.

Further, the method for producing a structural material according to the present invention is characterized in that a material mainly composed of volcanic ash is directly subjected to water plasma spraying on a substrate to form a volcanic ash sprayed layer. After forming a lower layer by spraying a material mainly composed of metal or ceramic on the material, forming a volcanic ash sprayed layer by water plasma spraying a material mainly composed of volcanic ash on the lower layer. It is characterized by. The underlayer is gas-sprayed or water-plasma-sprayed.

Preferably, the surface of the substrate to be treated is blasted, and more preferably, the surface of the volcanic ash sprayed layer is melted. This surface melting treatment uses a gas or water plasma spraying machine, and its operating conditions may be the same as those at the time of spraying, and may be performed by operating without supplying a sprayed material.

The main components of volcanic ash are alumina,
Silicon oxide, iron oxide, etc., and approximately 60 to 70% silicic acid;
It is composed of about 15% alumina and oxides such as iron and alkaline earth. The particle size of the volcanic ash varies depending on the location of the ash fall, but is generally 0.01 to 10 mm.
1 mm or less occupies about 40%, and 0.1 mm or more occupies about 60%. Further, since the volcanic gas adhering to the volcanic ash particles is composed of sulfate ions or chloride ions, it easily combines with water to form hydrochloric acid or sulfuric acid. For this reason, it is generally known that the pH is as low as about 4, and the acidity is exhibited.

Here, the results of chemical analysis of the Fugendake sediment, Shirahashi Shirasu and Sakurajima volcanic ash are shown in Table 1 below. The components of the volcanic ash of Miyakejima, on which the present inventors particularly conducted experiments, will be described in detail in an embodiment described later separately from Table 1 separately from Table 1.

[0011]

[Table 1]

Each type of volcanic ash is close to a normal spray component, and does not particularly hinder the spray property at the time of coating. In addition, volcanic ash contains harmful components such as sulfur (not sulfuric acid but simple sulfur or sulfide) and other components. However, water plasma spraying has a flame temperature of up to 30,000 ° C, so it is decomposed. It is removed by evaporation.

The water plasma spraying used in the present invention is also called water-stabilized plasma spraying and uses water vapor as a plasma stabilizing gas, and uses ordinary Ar, N ₂ , H ₂ , He gas or the like. Spraying capability compared to gas plasma spraying (spraying amount per hour is about 10
Times), the cost of spraying can be reduced because water is used instead of those gases.

In the present invention, since the base material is the basis of the shape of the final product, if a metal material such as aluminum is used as the base material, even a large structural material can be manufactured with high dimensional accuracy. Furthermore, by using steel or the like having strength as a device, it is possible to obtain a high-strength structural material having a ceramic tile-like appearance.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a structural material and a method for manufacturing the same according to the present invention will be described below with reference to the accompanying drawings.

(Chemical Composition of Miyakejima Volcanic Ash) First, Table 2 shows the chemical composition of Miyakejima volcanic ash before and after water plasma spraying. The volcanic ash used in Examples 1 to 6 described below is the Miyakejima volcanic ash.

[0017]

[Table 2]

(Conditions for thermal spraying) Next, the following Examples 1 to 6
Table 3 shows the conditions of the water plasma spraying and the gas spraying performed in the above. The conditions shown here are the same as the conditions usually processed in each thermal spraying.

[0019]

[Table 3]

(Example 1, see FIG. 1) After the outer surface of a circular pipe 11 made of carbon steel was blasted with alumina, the outer circular pipe 11 was mounted on a turntable, and 80% Ni--
20% Al (wt%) was thermally sprayed to a thickness of 100 µm to form the lower embossed layer 12.

Next, while rotating the circular pipe 11 to supply cooling air to the inner surface of the pipe, 5 volcanic ash is removed by a water plasma spraying machine.
Thermal spraying is performed with a target thickness of 00 μm,
Was formed. After thermal spraying, it was left in the air and cooled naturally.

(Example 2, see FIG. 2) One side of a carbon steel plate 21 was brassed with alumina, and then 80% with a gas spraying machine.
% Ni-20% Al (wt%) was thermally sprayed with a target thickness of 100 μm to form the lower filling layer 22. Further, ZrO ₂ -8% Y ₂ O ₃ (wt%) was added to 30
The underfill layer 23 was formed by thermal spraying with a target thickness of 0 μm.

Next, the volcanic ash was measured for 1 m using a water plasma spraying machine.
Thermal spraying was performed with a target thickness of m to form a volcanic ash sprayed layer 25. After that, the supply of the volcanic ash was stopped, and the surface layer was melted by heating with a water plasma spraying machine. After that, it was left in the air and cooled naturally.

(See Example 3, FIG. 3) Fe-13% Cr
(Wt%) After the outer surface of the steel pipe 31 was brassed with alumina, 80% Ni-20% Cr (wt
%) With a target thickness of 200 μm,
Was formed. Further, ZrO ₂ −
8% Y ₂ O ₃ (wt%) was sprayed with a target of a thickness of 300 μm to form the lower filling layer 33.

Next, volcanic ash was removed by a water plasma spraying machine.
Thermal spraying was performed with a target thickness of 5 mm to form a volcanic ash sprayed layer 35. After thermal spraying, it was left in the air and cooled naturally.

(Example 4, see FIG. 4) After the outer surface of the aluminum steel pipe 41 was brassed with alumina, 80% Al-20% Ni (wt%) was 100 μm with a gas spraying machine.
The lower embossed layer 42 was formed by thermal spraying with the target thickness. Further, an equal weight mixture of Al ₂ O ₃ and volcanic ash was sprayed with a water plasma spraying machine to a thickness of 500 μm as a target, and the lower layer 43 was sprayed.
Was formed.

Next, the volcanic ash was reduced to 0 by a water plasma spraying machine.
Thermal spraying was performed with a target of 8 mm in thickness to form a volcanic ash sprayed layer 45. After thermal spraying, it was left in the air and cooled naturally.

(See Example 5, FIG. 5) The surface of an ALC (lightweight foamed concrete) plate 51 is directly sprayed with volcanic ash with a target of 1 mm in thickness by a water plasma spraying machine, and a volcanic ash sprayed layer 55 is formed. Formed. After that, the supply of the volcanic ash was stopped, and the surface layer was melted by heating with a water plasma spraying machine.
After that, it was left in the air and cooled naturally.

(See Example 6, FIG. 6) Zn was sprayed on the surface of an FRP (glass fiber reinforced plastic) plate 61 with a gas spraying machine to a thickness of 200 μm as a target, and an underlayer 62 was formed.
Was formed. In addition, 80% Ni-20 by gas spraying
% Al (wt%) was thermally sprayed with a target thickness of 200 μm to form the lower filling layer 63.

Next, the volcanic ash was reduced to 0 by a water plasma spraying machine.
Thermal spraying was performed with a target thickness of 6 mm to form a volcanic ash sprayed layer 65. After thermal spraying, it was left in the air and cooled naturally.

(Appearance of Examples) The results of observation of the appearance of Examples 1 to 4 are summarized in Table 4. All of them were black, and no delamination or falling off of the sprayed volcanic ash layer was observed, and no abnormality was observed.

[0032]

[Table 4]

(Heat cycle test) Examples 1 to 4
About 105 ° C. to evaluate durability (corrosion resistance)
A heat cycle test in which one cycle of holding in air for 50 minutes and then immersing in normal temperature water for 10 minutes,
50 cycles were performed while checking every 10 cycles, and the results are summarized in Table 5. As a comparative example, a test was conducted by adding ordinary carbon steel (SPCC), and the results are shown in Table 5.

As a result of the heat cycle test, remarkable red rust was observed in the carbon steel slab as a comparative example, whereas in Examples 1-4, there was no abnormality such as cracking or peeling, and no rust was generated. I was not able to admit.

[0035]

[Table 5]

(Tensile test) In order to investigate the effect on the material strength, a JIS No. 5 test piece was prepared using carbon steel (SPCC).
And a tensile test was performed. The results are summarized in Table 6. In each of Examples 1 to 4, no significant difference such as a decrease in strength was observed as compared with the carbon steel as the base material.

[0037]

[Table 6]

(Evaluation of Examples 5 and 6) In Example 5, no cracks or other abnormalities were observed in appearance, and the samples were sound. When a bending test was performed based on JIS A5416, no significant difference was found.

In Example 6, no cracks or other abnormalities were observed in appearance, and the sound was sound. Also, JISK
When a bending test was performed based on 6919, no significant difference was found.

(Other Embodiments) The structural material and the method for manufacturing the same according to the present invention are not limited to the above-described embodiments, but can be variously modified within the scope of the invention.

In particular, the conditions of water plasma spraying and gas plasma spraying are arbitrary, and preferable materials such as a base material and an underlayer can be arbitrarily selected.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment.

FIG. 2 is a sectional view showing a second embodiment.

FIG. 3 is a sectional view showing a third embodiment.

FIG. 4 is a sectional view showing a fourth embodiment.

FIG. 5 is a sectional view showing a fifth embodiment.

FIG. 6 is a sectional view showing a sixth embodiment.

[Explanation of symbols]

11, 21, 31, 41, 51, 61 ... base material 12, 22, 23, 32, 33, 42, 43, 62, 6
3 ... Lower layer 15,25,35,45,55,65 ... Volcanic ash sprayed layer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takezo Sasaki 3-13-10 Nishigaoka, Kita-ku, Tokyo Inside the Tokyo Metropolitan Industrial Research Institute (72) Inventor Akio Moto 3-13-10 Nishigaoka, Kita-ku, Tokyo No. Tokyo Metropolitan Industrial Technology Research Institute (72) Inventor Seiji Kataoka 3-13-10 Nishigaoka, Kita-ku, Tokyo Tokyo Metropolitan Industrial Technology Research Institute (72) Inventor Masaharu Nakamori 1-9-9 Jokoji Temple, Amagasaki City, Hyogo Prefecture No. 1 Inside Osaka Fuji Industrial Co., Ltd. (72) Katsuhiro Yanagura, Inventor 1-9-1, Jokoji Temple, Amagasaki City, Hyogo Prefecture Inside Osaka Fuji Industry Co., Ltd. (72) Takayuki Aisaka 1-9-1, Jokoji Temple, Amagasaki City, Hyogo Prefecture Osaka Fuji Industrial Co., Ltd. (72) Inventor Sadayoshi Nakajima 1-24-10 Higashi-Nippori, Arakawa-ku, Tokyo Sanko Techno Co., Ltd. F-term (reference) 4K0 31 AA01 AA05 AA08 AB02 AB03 AB04 AB08 CB14 CB18 CB26 CB42 CB43 CB48 DA01 DA04 EA03

Claims (7)

[Claims] A structural material comprising: a base material; and a sprayed volcanic ash layer mainly composed of volcanic ash sprayed on the base material. 2. A base material, a base layer mainly composed of metal or ceramic sprayed on the base material, and a volcanic ash sprayed layer mainly composed of volcanic ash sprayed on the base layer, A structural material comprising: 3. The structural material according to claim 2, wherein the underfill layer is a gas-sprayed layer mainly composed of metal or ceramic and / or a water-plasma-sprayed layer. 4. A method for producing a structural material, wherein a material mainly composed of volcanic ash is sprayed on a substrate with water plasma to form a volcanic ash sprayed layer. 5. A step of spraying a material containing metal or ceramic as a main component on a base material to form a lower filling layer, and performing a water plasma spraying of a material containing volcanic ash as a main component on the lower filling layer. A method for producing a structural material, comprising forming a volcanic ash sprayed layer. 6. The method according to claim 4, further comprising blasting the surface of the base material to be treated. 7. The method according to claim 4, wherein the surface of the volcanic ash sprayed layer is subjected to a melting treatment.
A method for producing the structural material described in the above.