JPS61201676A - Method of bonding ceramic and metal - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a method for bonding ceramics and metals.

(Prior art) The main side plate of a coal-fired boiler centrifugal fan undergoes erosion due to fly ash collision during operation, requiring repair or replacement after a short operating time, resulting in a reduction in boiler operating efficiency and a risk of repair or replacement. The cost required for replacement is large and the economic loss is large.

Therefore, attempts have been made to affix ceramics to the surface of metal material members that are subject to the above-mentioned ash erosion to improve wear resistance and extend maintenance intervals.

Generally, as a method for attaching ceramics to the surface of a metal material, an industrially practical method is attachment using an adhesive.

FIG. 2 shows a cross-sectional configuration of a portion where ceramics are adhered to the surface of a metal material using an adhesive. 01 is a metal material base material, and the material used is rolled steel for welded structures or high-tensile steel.

02 is a ceramic material, and alumina is most often used, but silicon nitride, zirconia, silicon carbide, etc. are also used. 03 is an adhesive part.

However, the shear strength of the bonded part by the above method is
Epoxy adhesives are low at about 5 kg/+m" and acrylic adhesives are about I Kll/m", and when applied to parts of rotating equipment such as coal-fired boiler centrifugal fans, they can be used to reduce centrifugal force, vibration, In many cases, the bonding material peels off in a short period of time due to thermal stress, etc., and in order to improve reliability, a bonding method that improves the shear strength of the bonded portion is desired.

(Problem to be solved by the invention) As a countermeasure against ash erosion in coal-fired boiler centrifugal fans, a method of bonding ceramics and metals with high bonding strength is required. In this case, most of the fracture locations are at the boundary between the ceramic and the adhesive, and improvements are particularly needed here.

The present invention aims to provide a method for firmly adhering ceramic material and metal.

(Means for Solving the Problems) That is, the present invention provides a method for bonding ceramics and metals, in which the surface of the ceramic to be bonded is roughened before firing, and the surface of the metal to be bonded is roughened before bonding. This is a method of bonding ceramics and metals, which is characterized by roughening the surface.

The method of bonding ceramics and metal according to the present invention can be advantageously applied to the manufacture of centrifugal fans for coal-fired boilers, coal dischargers for mills, and fuel pipes.

In the present invention, when bonding ceramics and metals, the bonding surface of the ceramics and metals is roughened in advance, but the hardness of the ceramics after firing is different from that of general grid materials, as shown in the table below. Ceramics are made to form a rough surface before firing because they are the same or harder, and because they have almost no plastic deformability after firing, they do not become rough even when the grid material collides with them. It is necessary to keep it. Generally, the surface roughness formed on ceramics and metals is about 5 to 80 microns.

Table 1 Adhesives used to bond ceramics and metals include epoxy resin/polyaminoid adhesives, epoxy resin/polysulfide adhesives, epoxy resin/silicone resin adhesives, and epoxy resin/polyamide adhesives. ,
Various adhesives are used, such as epoxy resin/phenol resin adhesive, epoxy/nitrile rubber adhesive, and cyanoacrylate adhesive.

An embodiment of the present invention will be described below with reference to FIG.

In Fig. 1, 1 is a metal material made of rolled steel for welded structures, Tl55M50.1a is a surface to be bonded that has been roughened before bonding the metal material 1, 2 is a ceramic material made of alumina, and 2a is a ceramic material 2. The bonding surface 3 was roughened before firing, and 3 was an epoxy resin/polyamide adhesive, and the bonding conditions were 120° C. for 30 minutes.

To roughen the bonded surface of the ceramic 2, the surface of the die on the bonded surface side was previously roughened by grid blasting to an average roughness of 40 μm during press molding before firing. After compaction, an average roughness of 35 μm was transferred to the adhesive surface of the ceramic molded body. This material was fired at 160°C for 1 hour.90 Also, to roughen the surface of the metal material 1 to be adhered, an alumina grid with a particle size of about 50 mesh was used before bonding, and compressed 9
Air (pressure 6 to 97 am'') was ejected from a plasto nozzle to impinge on the metal surface, resulting in an average roughness of about 30 microns.

Table 2 shows the shear test results of the bonded parts by the bonding method according to one embodiment of the present invention and the conventional bonding method.
9/-, whereas the method of the present invention is 5 K9/wa"
The above shear strength was obtained.

As described above, the present invention improves adhesive strength in bonding metal materials and ceramics, provides highly reliable wear-resistant members and heat-resistant members, and is very effective in practice.

Table 2

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing an aspect of the vertical method. Sub-agent 1) Meifuku agent Ryo Hagiwara - Figure 1 Party Figure 2

Claims (1)

[Claims] A method for bonding ceramics and metals, characterized by roughening the surface of the ceramic to be bonded before firing, and roughening the surface of the metal to be bonded before bonding. Method.