Method for preparing high-flatness wide pure-molybdenum metal plate

Abstract

The invention relates to a method for preparing a high-flatness wide pure-molybdenum metal plate. The method comprises the following steps of placing pure-molybdenum metal powder into a roller mill, and rolling-milling the pure-molybdenum metal powder to obtain a green body with a thickness of 0.5 to 1.4mm and a width of 120 to 160mm; placing the obtained pure-molybdenum metal plate green body into a high-temperature furnace, sintering the pure-molybdenum metal plate green body for 1 to 3 hours, and cooling and discharging the pure-molybdenum metal plate blank out of the high-temperature furnace; rolling-milling the pure-molybdenum metal plate blank preheated to required temperature for many times by using a roller mill; when the thickness deformation of the pure-molybdenum metal plate blank in the previous step reaches 20 to 40 percent, keeping the rolled plate at the temperature of 900 to 1,300 DEG C for 1 to 3 hours, and cooling and discharging the rolled plate out of the furnace; repeating the former two steps until the pure-molybdenum metal plate is rolled-milled to the thickness of about 0.5mm, placing the obtained pure-molybdenum metal plate into a four-roller mill, and rolling-milling the pure-molybdenum metal plate to the thickness of about 0.25mm; placing two pure-molybdenum metal plates with the thickness of 0.25mm into the four-roller mill in an overlaying way, and rolling-milling the pure-molybdenum metal plates to the thickness of less than 0.15mm. According to the method, procedures are simplified, the energy consumption is lowered, the consumption is lowered, the cost is reduced, and green production can be ensured.

Description

technical field [0001] The invention belongs to the technical field of pure molybdenum metal processing, in particular to a method for preparing a high flatness and wide pure molybdenum metal plate. Background technique [0002] Molybdenum metal is widely used in medical treatment due to its high melting point, high elastic modulus, good shock resistance and corrosion resistance, high electrical conductivity, thermal conductivity, excellent thermal fatigue resistance, and low expansion coefficient. , metallurgy, electric light source, semiconductor device, high temperature structural parts and nuclear industry and other fields, among which the plate is the most widely used. In the field of medical CT collimator and detector. With the development of CT machines, the flatness requirements of collimators have been increased from less than 0.03 to less than 0.02, which poses new challenges to the preparation of pure molybdenum plates. [0003] The traditional molybdenum plate ...

AI Technical Summary

Problems solved by technology

[0005] (1) The thickness of the billet is relatively large: the thickness of the billet produced by the existing preparation technology is at least 20 mm, and it is impossible to produce a thin plate green body below 3 mm

[0006] (2) Low green body density: the relative density of the green body produced by the existing technology generally does not exceed 50%

[0007] (3) Discontinuity of production: It is impossible to prepare continuous strip-shaped or large-area thin-plate green bodies with existing preparation technologies

Moreover, a green body of one specification needs to be matched with a set of molds of the corresponding specification, and the production flexibility is poor.

[0008] (4) Low yield rate of rolled plates: After sintering and hot and cold processing, the green body produced by the existing technology has a large loss, and the final rolled plate yield is low

Such as the production of thin plates with a thickness of 1mm, the overall yield is less than 40%

[0009] (5) Subsequent processing is difficult, resource and energy waste is large, and environmental pollution is serious: the green body produced by the existing technology has a large thickness and low relative density, which makes it difficult to further process the sintered slab, and high temperature must be used. Rolling, acid-alkali washing, multiple hot and cold processing and annealing, etc., waste resources and energy, and cause serious environmental pollution

[0010] (6) Large investment in follow-up processing equipment: There are many types and quantities of follow-up processing equipment, and most of them are processing equipment with high power and large tonnage, and the equipment investment is relatively large

[0011] (7) Occupies a large space: a larger processing site is required, and each process needs to be isolated from each other

[0012] (8) The traditional rolling technology adopts the method of single-sheet feeding and rolling. As the thickness of the material decreases during rolling, the total deformation of the material is limited, and the rolling process of the roll acting on the sheet during the rolling process Uneven force leads to large difference between the same plate after rolling, and rolling defects such as double-sided wave, single-side wave or medium wave after leveling will directly affect the flatness of the final product

[0013] (9) It is impossible to produce pure molybdenum metal sheets with a flatness of less than 0.1 (1 mm one-point measurement method), a thickness of 0.15 mm, and a width of more than 100 mm

Images