Sealing method for titanium-glass seal assembly

Abstract

The invention discloses a sealing method for a titanium-glass seal assembly. A to-be-sealed titanium metal shell and metal conductor core column are respectively pre-oxidized at the temperature of 300-500 DEG C, so the wettability of metal and glass is improved, and the problem that the wettability of titanium and a titanium alloy with glass is poor is solved; a low-temperature oxidation layer isused as a protective layer to prevent the metal from being excessively oxidized at high temperature; the consistency of a sintered assembly is further ensured, and subsequent surface treatment is facilitated; a sealing mold provided with a sealing part into a sintering furnace for sintering; nitrogen and hydrogen binary atmosphere is introduced as protective gas; the formation of nitrides and oxides on the metal surfaces of titanium and the titanium alloy is eliminated, and the seal assembly surface treatment process is eliminated; the sintered sealing part is subjected to heat preservation atthe temperature of 500-550 DEG C so as to eliminate stress in the seal assembly, potential safety hazards in the using process of the seal assembly are eliminated, then the titanium-glass seal assembly can be obtained after the seal assembly is cooled to the room temperature, and the process is simple.

Description

technical field [0001] The invention belongs to a metal-glass sealing process, in particular to a sealing method for a titanium-glass sealing component. Background technique [0002] Traditional metal-glass sealing generally adopts a high-temperature fusion sealing method to fuse metal and glass together. This method requires that the coefficient of thermal expansion between the metal and the glass is relatively matched, and the annealing process needs to be strictly controlled, so it has many shortcomings: 1) The fusion sealing process is difficult to control, and the process repeatability is poor, and the energy consumption is high; 2) ) The metals that can be used for sealing are limited to low-carbon steel, stainless steel and Kovar alloy, etc., and there are few types; 3) The performance and stability of the sealing product are poor due to the problem of process and material selection, and the sealing failure rate 4) The surface state of the product after sealing is re...

AI Technical Summary

Problems solved by technology

This method requires that the coefficient of thermal expansion between the metal and the glass is relatively matched, and the annealing process needs to be strictly controlled, so it has many shortcomings: 1) The fusion sealing process is difficult to control, and the process repeatability is poor, and the energy consumption is high; 2) ) The metals that can be used for sealing are limited to low-carbon steel, stainless steel and Kovar alloy, etc., and there are few types; 3) The performance and stability of the sealing product are poor due to the problem of process and material selection, and the sealing failure rate 4) The surface condition of the product after sealing is poor, causing great trouble to the subsequent surface treatment

[0004] However, there are many problems in the sealing process of titanium and titanium alloy materials, such as poor wettability with glass, high-temperature phase transition, etc., so it is difficult to achieve sealing with traditional glass. There are relatively serious defects in the alloy sealing interface. When disturbed by changes in the external environment, a large number of microcracks will be generated at the defects of the sealing interface, resulting in poor air tightness and poor insulation resistance.

At the same time, titanium and titanium alloys are easily oxidized at high temperatures, and different types of oxide layers are formed at different temperatures, which increases the difficulty of subsequent surface treatment

For this reason, the patent CN200810229958.2 proposes a titanium alloy sealing process, which needs to be sealed in an atmosphere of high-purity argon, and the temperature required for sintering the silicate system glass is as high as 960°C, but this The method does not solve the problem of poor wettability between titanium and titanium alloys and glass, and in the sealing process, an external abrasive tool is required for compression sealing. There is a big security risk in subsequent use

Images