CN109332389A - A magnesium alloy cross-rolled roll and its rolling method - Google Patents
A magnesium alloy cross-rolled roll and its rolling method Download PDFInfo
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- CN109332389A CN109332389A CN201811086600.9A CN201811086600A CN109332389A CN 109332389 A CN109332389 A CN 109332389A CN 201811086600 A CN201811086600 A CN 201811086600A CN 109332389 A CN109332389 A CN 109332389A
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- roll
- rolling
- rolled
- magnesium alloy
- working roll
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- 238000005096 rolling process Methods 0.000 title claims abstract description 36
- 229910000861 Mg alloy Inorganic materials 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title abstract description 6
- WYTGDNHDOZPMIW-RCBQFDQVSA-N alstonine Natural products C1=CC2=C3C=CC=CC3=NC2=C2N1C[C@H]1[C@H](C)OC=C(C(=O)OC)[C@H]1C2 WYTGDNHDOZPMIW-RCBQFDQVSA-N 0.000 claims description 10
- 238000003801 milling Methods 0.000 claims description 8
- 229910000831 Steel Inorganic materials 0.000 claims description 3
- 230000000994 depressogenic effect Effects 0.000 claims description 3
- 239000010959 steel Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 abstract description 4
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052749 magnesium Inorganic materials 0.000 abstract description 2
- 239000011777 magnesium Substances 0.000 abstract description 2
- 238000005336 cracking Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000003672 processing method Methods 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
- B21B27/02—Shape or construction of rolls
- B21B27/021—Rolls for sheets or strips
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Geometry (AREA)
- Metal Rolling (AREA)
Abstract
一种镁合金交叉轧制的轧辊极其轧制方法，属于轧制镁合金板材技术领域。特征是：上、下工作辊形状、结构相同，其辊身中有一端为“S”形，另一端是平直的；其轧制方法是：(1)将镁合金板坯沿长度方向输入轧机进行轧制，前两道次压下率<10%，第三道次压下率<20%，轧件长度达到成品要求；(2)第四道次将镁板旋转90°进行横轧；(3)第五道次将上工作辊向右、下工作辊对称地向左移动进行窜辊轧制，压下率<15%；(4)第六、七道次轧制是继续将上工作辊向右、下工作辊对称地向左移动，利用工作辊的平直段进行轧制，第六道次压下率<10%，第七道次压下率<1%，达到终轧。本发明的优点：①有效克服了轧件边裂的问题，提高了成材率；②细化了轧材的晶粒度，改善了力学性能。
A magnesium alloy cross-rolling roll and a rolling method belong to the technical field of rolling magnesium alloy sheets. The characteristics are: the shape and structure of the upper and lower work rolls are the same, and one end of the roll body is "S" shaped, and the other end is straight; the rolling method is: (1) Input the magnesium alloy slab along the length direction. The rolling mill is rolled, the reduction rate of the first two passes is less than 10%, the reduction rate of the third pass is less than 20%, and the length of the rolled piece meets the requirements of the finished product; (2) The fourth pass rotates the magnesium plate by 90° for cross-rolling ; (3) The fifth pass moves the upper work roll to the right and the lower work roll to the left symmetrically for roll shifting, and the reduction rate is less than 15%; (4) The sixth and seventh passes are to continue to roll the upper The work roll moves symmetrically to the right and the lower work roll to the left, and the flat section of the work roll is used for rolling. The reduction rate of the sixth pass is less than 10%, and the reduction rate of the seventh pass is less than 1% to achieve the final rolling. . The advantages of the invention are as follows: (1) the problem of edge cracking of the rolled material is effectively overcome, and the yield of finished products is improved; (2) the grain size of the rolled material is refined, and the mechanical properties are improved.
Description
Technical field
The invention belongs to roll magnesium alloy plate technical field, and in particular to a kind of roll of magnesium alloy tandem rolling and its
Milling method.
Background technique
Magnesium alloy is widely used metal material in current engineering, and main processing method is rolling, rolled edge rhegma wound
It is the key factor for influencing magnesium alloy plate production, the mechanism and elimination of side rhegma wound is illustrated there is presently no complete theory
Method, can only take constantly optimization processing method by the side of rolled piece split degree reduce.Exist in traditional processing technology
Deficiency be reduction system and mill speed unreasonable distribution in processing technology, crystal grain cannot be effectively refined, so that process
In to split degree serious on side, cause product qualification rate low, material loss is serious.
Roller system of rolling mill has a significant impact to magnesium alloy board rolling tool.Designed for magnesium alloy plate rolling at this stage
Roll shape has very much, the drafts and pressure dynamics of sheet material edge all cannot be preferably controlled, so that rolled piece edge amounts of thickness variation
Inconsistent with interior thickness variable quantity, causing the plate side after rolling to be split, degree is serious, not can guarantee the template and quality of finished product.
Summary of the invention
It is an object of the present invention to provide the rolls and its milling method of a kind of magnesium alloy tandem rolling, can be efficiently against existing
Technology there are the shortcomings that.
The invention is realized in this way it is characterized in that: as shown in Figure 1, upper and lower working roll shape, structure is identical, the body of roll
Have in left and right end one end be serpentine, the other end be it is straight, upper and lower working roll opposite direction is mounted in rolling-mill housing；Such as Fig. 2
Shown, the structure of upper and lower working roll is: lpFor the length of body of roll flat segments, lsFor the length of body of roll serpentine curved section；R2For
Serpentine curve and the tangent arc radius of flat segments, R1For serpentine curve and R2Arc radius that is tangent, being connected with roll neck；
R1=R2, tie point is tangent；Δ D is serpentine curve radial height, Δ D=0.2~0.5mm, lp:ls=4:1, R1=R2=(Δ
D2+ls 2)/4ΔD。
Milling method with above-mentioned working roll is:
(1), milling train progress will be inputted along its length with a thickness of 5~15mm, the magnesium alloy slab of 500~2000mm of width
Three passes: the first two percentage pass reduction is < 10%, deformation of rolled wire 80~90MPa of intensity, 0.2~0.5m/ of mill speed
s；Reduction ratio < 20% of third passage, deformation of rolled wire 120~130MPa of intensity, mill speed are 0.6~0.8m/s.Rolled piece is long
Degree reaches length required by finished product；
(2), four-pass is that magnesium alloy slab is rotated by 90 ° carry out transverse rolling by steel rotator, i.e. edge convexity rolls, will
Top working roll to the left, bottom working roll rolled symmetrically towards moving right, as shown in Figure 4；Its reduction ratio is 15%~25%, is rolled
Part deformation intensity is 170~180MPa, and mill speed is 0.3~0.5m/s, and rolling rear sheet shape is that cross section is raised for two sides
And in the shape of antisymmetry distribution, as shown in Figure 3；
(3), the 5th passage: by top working roll to the right, bottom working roll symmetrically towards moving left, roll shifting rolling is carried out, until rolling
Part two sides thickness area is depressed, and rolled piece is rolled flat, and reduction ratio is < 15%, and deformation of rolled wire intensity selects 110~120MPa, control
Mill speed is 0.3~0.5m/s；
(4), the six, the seven passes: by top working roll to the right, bottom working roll symmetrically towards moving left, utilize working roll
Flat segments rolled: reduction ratio < 10% of the 6th passage, deformation of rolled wire intensity select 70~80MPa, and mill speed is
0.6~0.8m/s；7th secondary control reduction ratio < 1%, deformation of rolled wire intensity select 40~50MPa, mill speed be 1.0~
1.3m/s realizes finish to gauge.
Advantages of the present invention and good effect are:
1. the drafts and pressure dynamics of rolled piece edge has been effectively ensured, rolled piece edge is made there are different pressures from middle section
Lower rate refines the grain size of rolled piece, improves mechanical property；
2. overcoming plate side splits the problem bad with template；
3. improving the lumber recovery of rolled piece.
Detailed description of the invention:
Fig. 1 is roller system of rolling mill structural schematic diagram；
Fig. 2 is upper and lower work roller structure schematic diagram；
Fig. 3 is the view profile of rolled piece after four-pass rolling；
Fig. 4 be top working roll to the left, bottom working roll moves right schematic diagram；
Fig. 5 be top working roll to the right, bottom working roll be moved to the left schematic diagram.
In figure, 1,1 ' --- upper and lower backing roll；2,2 ' --- upper and lower working roll；3 --- rolled piece；lp--- work rolls out
The length of straight section；ls--- the length of working roll sigmoid curve section；R1、R2--- sigmoid curve arc radius；Δ D --- sigmoid curve
Radial height；I --- the area rolled piece Zuo Hou；II --- the thin area of rolled piece；III --- the area rolled piece You Hou.
Specific embodiment
It elaborates with reference to the accompanying drawing with specific example to a specific embodiment of the invention.
Present embodiment uses four-high mill, using Varying-thickness rolling mode is intersected, utilizes the axial movement pair of working roll
Blank carries out plate forming processing.
Choose rolling kind be AZ31B type magnesium alloy, blank specification: 8 × 850 × 1000mm, trimmed size: (2~4) ×
(1930~1420) mm, mill speed: (0.2~2.0) m/s, the working roll of four-high mill used having a size of Φ 1000 ×
2500mm。
Work roller structure is:
(1), the length l of working roll flat segmentspWith the length l of working roll sigmoid curve sectionsThe ratio between be 4:1, take lp=
2000mm, ls=500mm, the radial height of sigmoid curve section are Δ D=0.5mm；
(2), the arc radius of sigmoid curve is R in working roll1=R2=(Δ D2+ls 2The Δ D=125000.125mm of)/4.
Its milling method carries out in following processing steps:
(1), magnesium alloy slab is rolled to three passages along its length, controls the 1st passage rolled piece reduction ratio ε1=
8.75%, deformation of rolled wire intensity 80MPa, mill speed ν1=0.3m/s；2nd passage rolled piece reduction ratio ε2=9.58%, rolled piece becomes
Shape intensity 80MPa, roll-force choose mill speed ν2=0.5m/s；Control the reduction ratio ε of the 3rd passage3=19.70%, rolled piece becomes
Shape intensity 125MPa, mill speed 0.8m/s；Rolled piece is subjected to length along its length, is rolled into required by strip finished product
Length l=(1930~1420) mm；
(2), the 4th passage by magnesium plate by steel rotator be rotated by 90 ° carry out transverse rolling edge convexity rolling, top working roll to the left,
Bottom working roll is two sides protrusion and is distributed in antisymmetry symmetrically towards moving right, as shown in figure 4, will roll plate and be rolled into cross section
Shape, as shown in Figure 3；The reduction ratio for controlling the passage is ε4=20.8%, deformation of rolled wire intensity selects 175MPa, mill speed
Choose 0.3m/s；
(3), the 5th passage roll shifting roll, top working roll to the right, bottom working roll symmetrically towards moving left, as shown in figure 5, extremely
Rolled piece two sides thickness area is depressed, and rolled piece is rolled flat；Control this percentage pass reduction ε5=11.9%, the selection of deformation of rolled wire intensity
110MPa, controlled rolling speed are 0.5m/s；
(4), the 6th, 7 passages: continue top working roll to the right, bottom working roll symmetrically towards moving left, utilize working roll
Flat segments rolled, until target thickness；In 6th passage, percentage pass reduction ε is controlled6=5.41%, deformation of rolled wire is strong
Degree selection 75MPa, mill speed 0.8m/s；7 passages, that is, extreme trace, controls the reduction ratio ε of the passage7=0.28%, it rolls
Part deformation intensity selects 40MPa, and controlled rolling speed is 1.2m/s, forms finished product plate, completes rolling.
The magnesium alloy plate even tissue that the present embodiment rolls out, lumber recovery is high, has good mechanical property, meets real
The demand of border production.
Claims (2)
1. a kind of roll of magnesium alloy tandem rolling, it is characterized in that: upper and lower working roll shape, structure is identical, the body of roll it is left and right
Have in end one end be serpentine, the other end be it is straight, upper and lower working roll opposite direction is mounted in rolling-mill housing；Upper and lower work
The structure of roller is: lpFor the length of body of roll flat segments, lsFor the length of body of roll serpentine curved section；R2For serpentine curve with it is straight
The tangent arc radius of section, R1For serpentine curve and R2Arc radius that is tangent, being connected with roll neck；R1=R2, tie point phase
It cuts；Δ D is serpentine curve radial height, Δ D=0.2~0.5mm, lp:ls=4:1, R1=R2=(Δ D2+ls 2)/4ΔD。
2. the milling method of the roll of magnesium alloy tandem rolling according to claim 1, it is characterised in that implementation steps are as follows:
(1), milling train will be inputted along its length with a thickness of 5~15mm, the magnesium alloy slab of 500~2000mm of width carries out three
Passes: the first two percentage pass reduction is < 10%, deformation of rolled wire 80~90MPa of intensity, 0.2~0.5m/s of mill speed；The
Reduction ratio < 20% of three passages, deformation of rolled wire 120~130MPa of intensity, mill speed are 0.6~0.8m/s, and length of rolled piece reaches
Length required by finished product；
(2), four-pass is that magnesium alloy slab is rotated by 90 ° carry out transverse rolling by steel rotator, i.e. edge convexity rolls, by upper work
Make roller to the left, bottom working roll rolled symmetrically towards moving right, reduction ratio is 15%~25%, and deformation of rolled wire intensity is 170
~180MPa, mill speed are 0.3~0.5m/s, and rolling rear sheet shape is that cross section is two sides protrusion and is distributed in antisymmetry
Shape；
(3), the 5th passage: by top working roll to the right, bottom working roll symmetrically towards moving left, roll shifting rolling is carried out, until rolled piece two
The area Ce Hou is depressed, and rolled piece is rolled flat, and reduction ratio is < 15%, and deformation of rolled wire intensity selects 110~120MPa, controlled rolling speed
Degree is 0.3~0.5m/s；
(4), the six, the seven passes: by top working roll to the right, bottom working roll symmetrically towards moving left, utilize the flat of working roll
Straight section is rolled, reduction ratio < 10% of the 6th passage, deformation of rolled wire intensity select 70~80MPa, mill speed be 0.6~
0.8m/s；7th secondary control reduction ratio < 1%, deformation of rolled wire intensity select 40~50MPa, and mill speed is 1.0~1.3m/
S realizes finish to gauge.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811086600.9A CN109332389B (en) | 2018-09-18 | 2018-09-18 | A kind of method of magnesium alloy cross rolling |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811086600.9A CN109332389B (en) | 2018-09-18 | 2018-09-18 | A kind of method of magnesium alloy cross rolling |
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| Publication Number | Publication Date |
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| CN109332389A true CN109332389A (en) | 2019-02-15 |
| CN109332389B CN109332389B (en) | 2020-06-05 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110216145A (en) * | 2019-07-10 | 2019-09-10 | 太原科技大学 | Milling method is split on a kind of magnesium alloy plate grain refining control side |
| CN110216146A (en) * | 2019-07-13 | 2019-09-10 | 太原科技大学 | Milling method is split on a kind of low-cost magnesium alloy plate control side |
| CN111389916A (en) * | 2020-03-26 | 2020-07-10 | 太原科技大学 | A Gradient Microstructure Control Method Based on Cross Variable Thickness Rolling |
| CN117483424A (en) * | 2023-11-17 | 2024-02-02 | 燕山大学 | An axially movable special-shaped roller and rolling method for improving edge cracks of magnesium alloy plates |
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| JPH06114414A (en) * | 1992-10-03 | 1994-04-26 | Sumitomo Metal Ind Ltd | Hot forming convex roller for shaping rolled channel and shaping method |
| CN1112463A (en) * | 1994-02-25 | 1995-11-29 | 石川岛播磨重工业株式会社 | Rolls for rolling mills and roll shifting rolling mills |
| CN1840253A (en) * | 2005-03-28 | 2006-10-04 | 宝山钢铁股份有限公司 | A backup roll matching the profile curve of the work roll of a continuously variable crown rolling mill |
| CN101045240A (en) * | 2006-03-29 | 2007-10-03 | 宝山钢铁股份有限公司 | Higher degree roller ablet to control edge shape of steel band |
| JP2009113090A (en) * | 2007-11-08 | 2009-05-28 | Mitsubishi Alum Co Ltd | Method for producing magnesium alloy sheet |
| CN101569892A (en) * | 2009-05-21 | 2009-11-04 | 上海交通大学 | Method for rolling AZ31 magnesium alloy through asynchronous longitudinal and transverse crossing |
-
2018
- 2018-09-18 CN CN201811086600.9A patent/CN109332389B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06114414A (en) * | 1992-10-03 | 1994-04-26 | Sumitomo Metal Ind Ltd | Hot forming convex roller for shaping rolled channel and shaping method |
| CN1112463A (en) * | 1994-02-25 | 1995-11-29 | 石川岛播磨重工业株式会社 | Rolls for rolling mills and roll shifting rolling mills |
| CN1840253A (en) * | 2005-03-28 | 2006-10-04 | 宝山钢铁股份有限公司 | A backup roll matching the profile curve of the work roll of a continuously variable crown rolling mill |
| CN101045240A (en) * | 2006-03-29 | 2007-10-03 | 宝山钢铁股份有限公司 | Higher degree roller ablet to control edge shape of steel band |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110216145A (en) * | 2019-07-10 | 2019-09-10 | 太原科技大学 | Milling method is split on a kind of magnesium alloy plate grain refining control side |
| CN110216145B (en) * | 2019-07-10 | 2020-12-15 | 太原科技大学 | A kind of magnesium alloy sheet fine-grained edge-crack-controlled rolling method |
| CN110216146A (en) * | 2019-07-13 | 2019-09-10 | 太原科技大学 | Milling method is split on a kind of low-cost magnesium alloy plate control side |
| CN111389916A (en) * | 2020-03-26 | 2020-07-10 | 太原科技大学 | A Gradient Microstructure Control Method Based on Cross Variable Thickness Rolling |
| CN117483424A (en) * | 2023-11-17 | 2024-02-02 | 燕山大学 | An axially movable special-shaped roller and rolling method for improving edge cracks of magnesium alloy plates |
| CN117483424B (en) * | 2023-11-17 | 2024-06-04 | 燕山大学 | Axially movable special-shaped roller for improving edge crack of magnesium alloy plate and rolling method |
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