CN1818095A

CN1818095A - Method and mould for producing face-centered cubic metal plate with fine grain

Info

Publication number: CN1818095A
Application number: CN 200610031359
Authority: CN
Inventors: 张新明; 杜予晅; 叶凌英; 罗智辉; 周卓平
Original assignee: Central South University
Current assignee: Central South University
Priority date: 2006-03-16
Filing date: 2006-03-16
Publication date: 2006-08-16
Anticipated expiration: 2026-03-16
Also published as: CN100396801C

Abstract

The invention opened a process for producing the face-centred cubic metal fine crystalline board. It is 45-80 degree angle of the pressed face and the press direction, then press the prepared board. The die of the process has the top die and the low die between which the metal board face is cant. It is 45-80 degree angle with the force direction. It can decrease the size of the crystal grain and improve the ND// (111) content, so it improve the deep punching performance of the face-centred cubic metal fine crystalline board, it is fit for the production of the Al and the A-alloy board.

Description

The method and the mould that prepare face-centered cubic metal plate with fine grain

Technical field

The present invention relates to a kind of method and mould for preparing face-centered cubic metal plate with fine grain.

Background technology

The metal current preparation of plates mainly contains hammer out and compresses and rolling two kinds, what hammer flattener compression made that metal is subjected to is the plane strain distortion, rolling is a kind of proximate plane strain distortion, because the two effect is similar substantially, and the rolling suitability for industrialized production that more adapts to, therefore adopt rolling method to produce sheet metal in the industry usually, the bcc metals sheet material such as the steel plate of this method processing, has well deep drawability preferably, plastic strain ratio r＞1, be used for face-centered cubic sheet metal preparation then owing to forming very strong ND ∥＜111〉the texture component cause aluminium and aluminum alloy rolling plate deep drawability relatively poor, its plastic strain ratio is very low, usually less than 0.8.In addition, the common grain-size of the sheet material that rolling deformation obtains is very thick, and size is often inhomogeneous, can't satisfy the desired organization condition of superplasticity (grain-size generally must less than 10 μ m).Common rolling method is that basic mechanical thermal treatment also can't obtain the grain-size below the 10 μ m because the total deformation quantitative limitation can't obtain very tiny grain structure even adopt with rolling.With the trade mark is that 1420 Al-Li alloys are example, and nominal composition is Al-5Mg-2Li2-0.1Zr, initial grain structure as shown in Figure 1, crystal grain is flats, RD, ND, three direction sizes of TD are about 210 μ m, 15 μ m, 45 μ m respectively.Its grain structure is seen Fig. 2 after carrying out hot rolling, though grain-size has very big reducing, also has some equiax crystal to occur, and much crystal grain still are flats, and its texture component is typical copper type texture, and { 111} face occupation rate is almost nil sees Fig. 3.Be the sheet material that example rolls into traditional method again with the rafifinal, grain-size is about 500～600 μ m, sees Fig. 4.Therefore face-centered cubic sheet metal deep drawability difference is a problem demanding prompt solution at present.

Summary of the invention

The object of the present invention is to provide a kind of method for preparing face-centered cubic metal plate with fine grain and mould that can effectively improve face-centered cubic sheet metal deep drawability and make its grain structure refinement.

The method that the present invention prepares face-centered cubic metal plate with fine grain comprises the θ angle that the load face that makes sheet material to be prepared and pressure direction are 45-80 °, exerts pressure to sheet material to be prepared then.

Prepare the mould of face-centered cubic metal plate with fine grain with the inventive method, have upper die and lower die, the face that upper die and lower die contact described sheet metal is the inclined-plane, and this inclined-plane becomes 45-80 ° θ angle with application of force direction.

The present invention makes material (sheet material to be prepared) in compression process, not only be subjected to reactive force perpendicular to compression direction, also be subjected to being parallel to the shearing force of steel slab surface, so strong tangential strain is introduced in the hammer flattener compression or plane strain compression of slab, not only more deformation energy can be stored in the sheet material, grain-size is reduced greatly, can also in sheet material, form intensive and shear texture, improve ND ∥＜111〉texture content, especially also can increase plate face normal direction ND ∥＜111〉texture content greatly to center of area cubic metal, thereby improved the deep drawability of sheet material greatly, be specially adapted to the production of aluminium and aluminum alloy plate materials.

Description of drawings

Fig. 1 is the initial grain structure figure of 1420 Al-Li alloys.

Fig. 2 is the grain structure figure of the sheet material after 1420 Al-Li alloys use traditional method rolling.

Fig. 3 is the described sheet material of Fig. 2 (111) utmost point figure.

Fig. 4 is with the rolling rafifinal grain structure figure of traditional method.

Fig. 5 is first kind of structural representation of mould of the present invention.

Fig. 6 is second kind of structural representation of mould of the present invention.

Fig. 7 is the third structural representation of mould of the present invention.

Fig. 8 is with 1420 rolling Al-Li alloy sheet material grain structure figure of the inventive method.

Fig. 9 is the described sheet material of Fig. 8 (111) utmost point figure.

Figure 10 is with the rolling rafifinal sheet material grain structure figure of the inventive method.

Embodiment

Embodiment one:

Fig. 5-Fig. 7 is three kinds of different shapes of mould of the present invention, patrix 2 and counterdie 3 are all arranged, and the contact surface of upper die and lower die and metal slabs is the inclined-plane, application of force direction and inclined-plane angle, the θ angle is 45 °-80 °, preferably between 50 °-60 °, during use metal slabs 1 are placed between patrix 2 and the counterdie 3.

Example two:

Initial slab is the thick hot-rolled sheet of 8.5mm, is through melting, semicontinuous casting, mills face, homogenizing, hot rolled 1420 Al-Li alloys, and 1420 is the Russian wrought aluminium alloy trade mark.

Mould adopts Fig. 5-any one mould shown in Figure 7, and θ elects at the angle 60 ° as.

Slab is placed between the mould (2,3), should adopt examples of suitable lubricants between mould and the metal slabs.The pressure that applies a little is to keep the position stability of slab and mould.Mould and slab are heated to 300 ℃, and insulation 10min depresses by every time dependent variable of 10%, reach about 90% up to total deformation, every time 6 seconds of residence time, compression finish rapidly with cold-water quench to room temperature to keep high temperature microstructure.Grain structure after the compression (vertical section) is seen Fig. 8, and its grain-size reduces greatly, and average grain size is about 3.5 μ m.Fig. 9 for the compression after { 111} utmost point figure can see, { 111} face occupation rate improves greatly than rolling plane deformation state.Make Al-Li alloy sheet material have good deep drawability.By the common sense in present technique field as can be known, the present invention adapts to equally to other aluminium alloy.

Example three:

Initial slab is the rafifinal hot-rolled sheet, and its foreign matter content is about Fe 7 * 10 ^-8-10 * 10 ^-6, Si 7 * 10 ^-6-10 * 10 ^-6, Cu 30 * 10 ^-6-40 * 10 ^-6, ingot casting mills face after 610 ℃ of long-time homogenizing are handled, be hot-rolled down to about 7mm then.Adopt mould as shown in Figure 2, choose θ=55 °, texturing temperature is 500 ℃.

Slab is placed between the mould (2,3), and the pressure that applies a little is to keep the position stability of slab and mould.Mould and slab are heated to 500 ℃, insulation 10min, depress by every time dependent variable of 10%, reach about 90% up to total deformation, every time 6 seconds of residence time, air cooling after compression finishes, its grain structure (vertical section), see Fig. 7, grain-size is littler (comparison diagram 4 traditional technologys are rolling) obviously.

Therefore the present invention can process face-centered cubic sheet metals such as good aluminium of deep drawability and aluminium alloy, use the present invention to prepare some other processing parameter of face-centered cubic metal plate with fine grain, all do not have particular requirement as Heating temperature, soaking time, every time volume under pressure and interval time, can adopt the processing parameter of traditional hammer flattener compression.

Claims

1, a kind of method for preparing face-centered cubic metal plate with fine grain comprises the θ angle that the load face that makes sheet material to be prepared and pressure direction are 45-80 °, exerts pressure to sheet material to be prepared then.

2, method according to claim 1 is characterized in that described angle is 50-60 °.

3, a kind of mould with the described method preparation of claim 1 preparation face-centered cubic metal plate with fine grain is characterized in that having upper die and lower die, and the face that upper die and lower die contact described sheet metal is the inclined-plane, and this inclined-plane becomes 45-80 ° θ angle with application of force direction.

4, mould according to claim 3 is characterized in that described angle is 50-60 °.