A kind of preparation method of ternary alloy sealing material

Abstract

The invention discloses a preparation method of a ternary alloy sealing material. The ternary alloy sealing material comprises, by mass, 60-67% of Ag, 25-30% of Cu and 8-12% of In. The preparation method comprises the steps that 99.99% Ag and a 99.9% Cu pipe are obtained, and 99.99% In is placed in the 99.9% Cu pipe; the raw materials are placed in a vacuum medium-frequency smelting furnace, vacuumization is performed till vacuum pressure reaches 0.02-0.04 MPa, and inert gas is input after temperature is increased to reach 1000-1100 DEG C; heat preservation is performed for 20-30 min, and sufficient stirring and casting are performed through the medium-frequency furnace; a cast ingot is laced in a vacuum annealing furnace for annealing, the temperature is 600-700 DEG C, the heat preservation time is 2-5 h, and the cast ingot is taken out after the temperature reaches 60 DEG C; and annealing is performed after the cast ingot is calendered by 1-2 mm, the temperature is 500-600 DEG C, heat preservation time is 2-3 h, inert gas is input, and the cast ingot is rolled to 0.1-0.12 mm after being cooled. The sealing material is high in cleanliness and good in welding performance.

Description

technical field

[0001] The invention relates to a sealing material for a vacuum electron tube in the vacuum electronics industry, in particular to the preparation of a ternary alloy sealing material of Ag, Cu and In. Background technique

[0002] In the vacuum tube sealing industry, due to the high frequency of use of vacuum tubes and the need to maintain a vacuum state, the requirements for sealing materials for vacuum tubes, especially ceramics and metals, and metals and metals are relatively high. At present, the most widely used solders are B-Ag72Cu and AgCuNi solders. Compared with B-Ag72Cu and AgCuNi solders, the soldering temperature of AgCu27-In12 solders is about 80-100°C lower. It can be used as vacuum brazing and grading for vacuum tube sealing. Brazing. And due to the addition of In, the solder also has good wettability to copper, nickel, steel and Kovar alloy, and has better welding performance and lower vapor pressure. However, because the as-cast structure o...