JPH02187591A - Molybdenum floorplate and manufacture thereof - Google Patents

Abstract

PURPOSE:To improve the yield of fired products by forming on a plane for laying fired objects specific fine projections in such a manner as to reduce the contact area between fired objects and said plane so as to reduce the occurrence of fusion adhesion under high temperatures. CONSTITUTION:The process of manufacturing molybdenum floorplate comprises preparation of a molybdenum plate having a plane whereon fired objects, such as ceramics, are laid and surface treatment whereby fine projections are formed all over said plane. In the surface treatment, for example, a technique of blasting is used to form fine projections on the plane of the molybdenum plate. For the surface treatment, it is conditioned specifically that a level part wherein the maximum rise (Rmax) among the fine projections does not exceed 10mum should not be formed to a length of 0.5m/m or more in a direction parallel to said plane and that the fine projections should include at least one with Rmax of 15mum or more within 1m/m. In practicing the blasting, the abrasive grains employed are specified in size, a uniform pressure is applied in blowing the abrasive grains at all points on said plane, and the time of the treatment with the abrasive grains per unit area is made constant. During this surface treatment, the surface roughness is measured with a tester and only the products which have been proved good re picked out.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a molybdenum base plate for firing ceramics and a method for manufacturing the same.

[Prior Art] A molybdenum plate, which is a high point metal, is generally used as a base plate for firing ceramics such as IC packages and rare earth magnets. This kind of molybdenum floor plate is 140
Since it is placed in an electric furnace of 0 to 1600['C],
Reaction with the fired material such as ceramics placed thereon, ie, welding phenomenon at high temperatures, becomes a problem. The welding phenomenon inevitably has an adverse effect on the fired product, and in the worst case, it becomes impossible to commercialize the product. For this reason, conventionally, a warped denum floor plate with fine protrusions formed on its surface by blasting or honing has been used to reduce the contact area with ceramics.

[Problems to be Solved by the Invention] However, the main focus of conventional blasting methods was only on roughening the surface of molybdenum floor plates, so fine protrusions were unevenly distributed on molybdenum floor plates surface-treated by such methods. It is formed by Therefore, depending on the location where the ceramic is placed, the contact area becomes large, and there is a problem in that it is not possible to effectively prevent the phenomenon of welding between the molybdenum base plate and the ceramic. Therefore, the technical object of the present invention is to provide a molybdenum base plate and a method for manufacturing the same, which can significantly reduce the welding phenomenon at high temperatures and improve the yield of fired products such as ceramics.

c Means for Solving the Problem] According to the present invention, in a molybdenum base plate having a flat part on which a fired product is placed and in which fine protrusions are formed, the maximum peak value is 10[ The distance between the fine protrusions in the direction parallel to the plane part exceeds 0.5 [-/m]
], and the distance in the parallel direction to the plane part of the fine protrusions exceeding 15 [μl] at the maximum peak value is 1 [s/
A molybdenum floor plate is obtained, which is formed so as not to exceed s] and has a reduced contact area between the flat portion and the fired product.

Further, according to the present invention, in the method for manufacturing a molybdenum floor board, which includes a surface treatment step of forming fine protrusions on the entire flat surface of the molybdenum floor board, the surface treatment step has a maximum peak value of more than 10 [μ]. The distance between the fine protrusions in a direction parallel to the plane part does not exceed 0.5 Cs/m,
Moreover, the method for producing a molybdenum floor plate is characterized in that the distance between the fine projections having a maximum peak value exceeding 15 [μ11] in a direction parallel to the plane portion does not exceed 1 [m/+g]. can get.

[Example] Hereinafter, a method for manufacturing a molybdenum floor plate according to an example of the present invention will be described.

The method for manufacturing a molybdenum floor plate according to this embodiment includes a step of preparing a molybdenum plate having a flat surface on which a fired product such as ceramics is placed, and a step of forming fine protrusions on the entire surface of the flat surface of the prepared molybdenum plate. and a surface treatment step for forming the surface. In the preparation step, an existing molybdenum plate may be prepared, or a molybdenum plate formed by subjecting molybdenum material obtained by powder metallurgy to hot rolling and rolling processing, for example, may be prepared.

In the surface treatment step, fine protrusions are formed on the flat part of the molybdenum plate using, for example, a well-known blasting method. At least 1 ax fine protrusion is not formed over a length of 0.5 [m/m] or more in the direction parallel to the plane part ax, and has an R15 [μI] or more during 1' [s/s]. Set specific conditions so that each exists. In other words, in the blasting method, 1) the size of the abrasive grains to be used is specified, 2) the discharge pressure (spraying pressure) of the abrasive grains is made uniform over the entire flat surface, and 2) the processing time per unit area of the abrasive grains is Make it constant. Whether or not the specific conditions are satisfied is determined by measuring with a surface roughness meter after or during the surface treatment process, and only those that are found to be good are selected. Bad examples (a) and (b) and good examples (c) are listed in Figure 1 of the attached drawings for reference.

Table 1 shows the experimental results when ceramics were fired using the molybdenum base plate surface-treated in this manner, together with the results obtained using the molybdenum base plate surface-treated by conventional means.

Table 1 However, 72 molybdenum floor plates were used.In this way, in the flat part of the molybdenum base plate, the flat part with the maximum peak value of microprotrusions of 10 [μIl] or less is 0.5 [ta/ m ] or more, and the maximum peak value is 15 [μ■] or more.
Since at least one is present between [s/m], the contact area between the two can be reduced regardless of the placement position of the ceramic. As a result, the rate of occurrence of welding phenomena at high temperatures has been significantly suppressed, and it has become possible to improve the yield of ceramics.

[Effects of the Invention] As described above, the present invention provides a molybdenum base plate and a method for manufacturing the same, which significantly reduces the occurrence of welding between the base plate and the fired product under high temperatures and improves the yield of the fired product. can do.

[Brief explanation of the drawing]

Claims (2)

[Claims] (1) In a molybdenum base plate having a flat part on which a fired product is placed and in which fine protrusions are formed, the flat part of the fine protrusions having a maximum peak value exceeding 10 [μm] The distance in the parallel direction to the flat part of the fine protrusions does not exceed 0.5 [m/m] and exceeds 15 [μm] at the maximum peak value, and the distance in the parallel direction is 1 [m/m]. A molybdenum floor plate characterized in that the contact area between the flat part and the fired product is reduced. (2) In a method for manufacturing a molybdenum floor plate that includes a surface treatment step of forming fine protrusions on the entire flat surface of the molybdenum floor plate, the surface treatment step has a maximum peak value of 10 [μm].
] The distance between the fine protrusions in the direction parallel to the plane part exceeds 0.5 [m/m], and the maximum peak value is 15
A method for producing a molybdenum floor plate, characterized in that the distance between the fine protrusions in the direction parallel to the plane part exceeding [μm] does not exceed 1 [m/m].