SU618457A1 - Method of manufacturing fine-structure metal mesh - Google Patents

Description

(54) METHOD OF MANUFACTURING METAL SMALL-STRUCTURED GRIDS

This invention relates to the electroforming of metal fine mesh.

A known method of making metal grids includes creating a mesh relief on a metal matrix, isolating the surface of the matrix between depressions, applying a separating layer, electroplating a metal layer and removing the matrix by mechanical means or chemical dissolution 1.

Closest to the invention is a method of producing metallic fine-grained meshes by electrolytic deposition of a metal layer on a mesh matrix, the material of which does not form chemical compounds with the deposited metal, and the subsequent removal of the matrix by smelting 2.

However, the known methods do not allow obtaining fine-grained nets of refractory metals with a mesh size of 1-3 µm and a hole density of up to 10 per cm.

The proposed method eliminates this disadvantage due to the fact that during electrolytic deposition of metal on a grid matrix, the material of which does not form chemical compounds with the deposited metal, the latter is precipitated layer by layer at a layer thickness of 1-2 µm and intermediate annealing is carried out in vacuum or inert atmosphere at a temperature of 1.1-1.2 of the matrix melting point for its removal.

During annealing, diffusion and evaporation of the matrix material occurs through a layer of refractory metal.

This compresses the grid structure and reduces the internal stresses in the electrolytically deposited metal.

In accordance with the proposed method, a metal grid, for example copper, with a cell size of 7-g-15, μm and a step of 10-20 μm, is used as the initial matrix. A layer of refractory metal is electrolytically deposited on the defatted matrix. Metal deposition occurs from two sides. After a layer of 1-2 µm is grown, the coated matrix is annealed in vacuum or inert media of a temperature equal to 1.1-1.2 of the melting point of the matrix material, as a result of which 10 the matrix material is removed by evaporating j) ej layer of melted metal. Multiple

by repeating the deposition and annealing operation, the matrix material is completely removed, and the grid cell size is adjusted to 1–3 µm to obtain a hole density of 10 per 1 cm.

Example. To obtain a rhenium mesh, a tubular matrix of copper mesh with a mesh size of 7-15 µm and a step of 10-20 µm was used.

On the purified matrix precipitated rhenium from the electrolyte composition, g / l:

Ammonium Pfrenat 9

Sulfuric Acid25

Ammonium sulfate 50

At a temperature of 50 ° C and a current density of 20 a / dm with the superposition of ultrasonic vibrations of 16 kg with the use of two anodes, as a result of which the deposition of rhenium occurred on both sides. After deposition of a layer with a thickness of 2 microns, the matrix was annealed in a water slice (water at 1200 ° C for 15 microns). At this, copper atoms diffuse onto the surface of the deposited metal and evaporate, and the deposited stress

The operations of metal deposition and annealing were repeated until a tubular rhenium grid with a mesh size of 2-3 µm was obtained at a density of 10 per cm and a cross-sectional area of 10 µm, with no copper impurities exceeding 0.3%.

Thus, the proposed method, in contrast to the known ones, makes it possible to obtain fine-mesh nets of refractory metals with a mesh size of 1-3 µm and a hole density of up to 10 cm, which can be used in radio electronics and other engineering fields.

Claims (2)

1. The patent of Germany N 1212815, cl. 48 a, 7-00, 1966. 2.B. I. Treasurer. Electroforming industry. State publishing house of local industry of the RSFSR, M., 1955, p. 117119, 122-126.