Formwork for optimizing directional columnar crystal structure of high-temperature alloy blade

Abstract

The invention provides a formwork for optimizing a directional columnar crystal structure of a high-temperature alloy blade, and the formwork is used in a directional solidification device. Seeding columns are arranged between the bottom of a protruded part of a blade edge plate on the formwork and the top of a water-cooled chassis in a crystal growth direction, cavities are formed inside the seeding columns and are communicated with an inner cavity of the formwork, and a plurality of seeding columns are uniformly arranged in parallel and correspond to the cross section of the protruded part of the blade edge plate. According to the formwork disclosed by the invention, by virtue of a directional column crystal seeding technology, the high-temperature alloy blade produced by a directional solidification technology has a columnar crystal structure which grows axially; and as a harmful transverse crystal boundary is eliminated, high-temperature performance is obviously improved in comparison with an isometric crystal structure produced by a common precision casting method. After pouring, the seeding columns can be used for transferring heat of the edge plate vertically downwards, and simultaneously, the directional solidification process inside the columns can extend to the inside of the edge plate, so that the good columnar crystal structure is also formed in the edge plate.

Description

technical field [0001] The invention relates to precision casting of superalloy parts, in particular to a mold shell for optimizing the oriented columnar crystal structure used in the manufacture of superalloy columnar crystal blades. Background technique [0002] like figure 1 As shown, when manufacturing superalloy blades with directionally solidified columnar crystal structure, it needs to be carried out in a special directional solidification device. First, the ceramic formwork 1 is placed on the water-cooled chassis 5, and then the heater is turned on to preheat it above the alloy superalloy; then, the melted superalloy melt 2 is poured into the ceramic formwork 1, and the ceramic formwork The superalloy melt 2 at the bottom of 1 is firstly solidified by being quenched by the water-cooled chassis 5 . As the heat spreads downward and the ceramic mold shell 1 descends into the cooling zone, the superalloy melt 2 in the ceramic mold shell 1 directional solidifies from bo...

AI Technical Summary

Problems solved by technology

[0003] However, in the edge plate part of the blade, due to the sudden lateral increase of the cross section of the superalloy casting 3, the heat cannot be transmitted vertically downward, and the directional solidification is destroyed, thus forming coarse foreign miscellaneous crystal grains 4-1 and 4-2

The foreign miscellaneous crystal grains 4-1 and 4-2 of these edge plates have coarse grains and poor crystal orientation, which destroys the vertical columnar grain structure of the blade and seriously affects its performance; foreign miscellaneous crystal grains 4 -1 and 4-2 will even grow obliquely into the blade body part of the superalloy casting 3, causing greater impact

Images