COMPOSITE GETTER FOR MAINTAINING MEDIUM AND LOW VACUUM ENVIRONMENT, AND METHOD FOR PRODUCING SAME

摘要

A composite getter for maintaining medium and low vacuum environment comprises an elemental metal powder getter (3), an alloy powder getter (2), a drying agent powder (1) and a plastic film (4), wherein the elemental metal powder getter (3) and the alloy powder getter (2) are present respectively as one layer and stacked in the center position of the drying agent powder (1) to form a core-clad structure, which is packed in the plastic film (4). The elemental metal powder getter (3) is one or a combination of at least two selected from the group consisting of reduced iron powder, nickel powder and copper powder with a grain size range from 10 to 200 µm. The alloy powder getter (2) is one or a combination of at least two selected from the group consisting of strontium-lithium alloy powder, barium-lithium alloy powder and barium-magnesium alloy powder with a grain size range from 50 to 500 µm. The drying agent powder (1) is one or a combination of at least two selected from the group consisting of calcium oxide powder, strontium oxide powder and barium oxide powder with a grain size range from 20 to 200 µm. The plastic film (4) is breakable automatically under a pressure difference of one atmosphere. The performance properties of this composite getter is not affected when exposed to air for a short period of time. The method for producing the composite getter is also disclosed.