Sealing method of borosilicate glass and kovar alloy of solar collector tube

Abstract

The invention discloses a sealing method of borosilicate glass and kovar alloy of a solar collector tube, which relates to the matching sealing between the borosilicate glass and the kovar alloy under the condition of no transitional glass, and provides a novel method for the production of the metal glass middle-high temperature vacuum solar collector tube. In the method, the difference range of expansion coefficients of the kovar alloy and the borosilicate glass is 5 to 50 percent; the heating temperature at the sealing area is 300 to 1200 DEG C; the length of the sealing interface is about 3 to 8 mm; and the annealing treatment on the borosilicate glass and the kovar alloy are undertaken,the annealing temperature is 300 to 600 DEG C, and the time is 10 to 60 minutes. The method is free from utilizing a glass transitional section, so the production cost is saved, and the utilization rate of the solar collector tube is also improved while the sealing reliability is improved.

Description

technical field [0001] The invention belongs to the field of solar energy application, and in particular relates to a sealing method of high-silicon borosilicate glass and Kovar alloy in a high-temperature solar vacuum heat collection tube in metallic glass. technical background [0002] At present, in the manufacture of high-temperature solar vacuum heat collector tubes in metallic glass, due to the certain difference in thermal expansion coefficient between metal and glass, the sealing of metal and glass often cannot be directly sealed. To achieve matching sealing, a Or more than one transition section, the increase of the transition section increases the possibility of air leakage, resulting in a decrease in the airtightness of the entire device; the transition section is too long to increase the proportion of the transition device to the entire heat collecting tube, reducing the heat collecting tube. Heat collection efficiency; the domestic output of transition glass in ...

AI Technical Summary

Problems solved by technology

[0002] At present, in the manufacture of high-temperature solar vacuum heat collector tubes in metallic glass, due to the certain difference in thermal expansion coefficient between metal and glass, the sealing of metal and glass often cannot be directly sealed. To achieve matching sealing, a Or more than one transition section, the increase of the transition section increases the possibility of air leakage, resulting in a decrease in the airtightness of the entire device; the transition section is too long to increase the proportion of the transition device to the entire heat collecting tube, reducing the heat collecting tube. Heat collection efficiency; the transition glass in the middle has less domestic output and high price, which increases the production cost of heat collection tubes; the process is complicated and not suitable for large-scale production

Other non-matching sealing technologies are not yet mature, the glass tube is easy to burst, and it is difficult to meet the requirements of high temperature work

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