Method for improving cohesive strength of matrix and body of bead string

Abstract

A method for improving the cohesive strength of the matrix and the body of a bead string comprises the following steps: (1) placing a sintered bead string on a graphite base plate and placing one end with a long exposed portion of the body upwards; (2) selecting an appropriately-matched welding ring, and sleeving the welding ring on the end with the long exposed portion of the body to enable the welding ring to be completely sleeved on the body and disposed at the front end of the matrix; and (3) opening a mesh-belt sintering furnace, sending the bead string with the welding ring into the mesh-belt sintering furnace for welding, wherein the temperature of the mesh-belt sintering furnace reaches a temperature which can melt the welding ring during welding, and inletting a protective gas which is a mixed gas with 25% of nitrogen and 75% of hydrogen. The melted welding ring can gradually fill up the gap between the matrix and the body of the bead string to form an adhesive layer between the matrix and the body. According to the method for improving the cohesive strength of the matrix and the body of the bead string, bead strings produced through the method can effectively prevent the matrix from dropping off during the mid-post usage period, abnormal loss of tools can be reduced, the service life of the matrix can be prolonged, and the tool cost can be reduced.

Description

technical field [0001] The invention relates to the technical field of diamond bead manufacturing, in particular to a method for improving the bonding strength between a beaded carcass and a substrate. Background technique [0002] At present, the beading of the diamond wire saw is composed of two parts, one is the beading carcass, and the other is the beading matrix. In the existing hot pressing sintering process, the bonding between the beaded carcass and the substrate is mainly achieved by the following aspects: first, the radial flow of the powder under pressure during the hot pressing process; second, the coating on the surface of the substrate Plating, such as nickel or copper. However, factors such as thermal expansion and contraction of the powder during the sintering and cooling stage, or fluctuations in the sintering density of the beaded matrix (including the circumferential direction), or fluctuations in the quality of the coating on the surface of the substrate...

AI Technical Summary

Problems solved by technology

However, factors such as thermal expansion and contraction of the powder during the sintering and cooling stage, or fluctuations in the sintering density of the beaded matrix (including the circumferential direction), or fluctuations in the quality of the coating on the surface of the substrate, etc. will cause the beaded matrix and the substrate. weak bond

[0003] In addition, in the field of full-automatic production of beading, because the existing automatic cold press can only produce beading rings, the beading rings cannot be formed together with the matrix, and most of the sintering uses pressureless sintering technology to produce beads. The bonding between the carcass and the matrix is ​​only achieved by the natural shrinkage of the powder, and the bonding between the carcass and the matrix is ​​not firm

This will cause the following problems. First, there is a gap at the connection between the beaded matrix and the matrix after sintering. Second, the matrix will fall off during the field use of the wire saw, which not only increases the abnormality of the wire saw to a certain extent. Loss, reducing the life of the wire saw, but also cause safety hazards

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