CN107604242A

CN107604242A - Cold rolled automobile sheet and preparation method thereof

Info

Publication number: CN107604242A
Application number: CN201710649498.8A
Authority: CN
Inventors: 黄利; 张玮; 张秀飞
Original assignee: Baotou Iron and Steel Group Co Ltd
Current assignee: Baotou Iron and Steel Group Co Ltd
Priority date: 2017-08-02
Filing date: 2017-08-02
Publication date: 2018-01-19
Anticipated expiration: 2037-08-02
Also published as: CN107604242B

Abstract

The present invention relates to a kind of cold rolled automobile sheet and preparation method thereof.The chemical composition of the cold rolled automobile sheet includes by weight percentage：C：0.01~0.05%, Si：0.01~0.04%, Mn：0.10~0.50%, P≤0.02%, S≤0.01%, N≤0.004%, O≤0.003%, Al：0.015~0.035%, RE (Ce)：>=0.0010%, remaining is iron and other inevitable impurity.Above-mentioned preparation method includes：Using low-carbon continuous casting billet as hot rolling raw material, hot rolling, cold rolling, bell-type annealing and smooth are carried out successively.Silicon, phosphorus contain relatively low in cold rolled automobile slab provided by the invention, and O, N content are relatively low, and product has excellent deep drawability.

Description

Cold rolled automobile sheet and preparation method thereof

Technical field

The present invention relates to metallurgical material technical field, more particularly to cold rolled automobile sheet and preparation method thereof.

Background technology

Flat cold-rolled sheet is the kind that dosage is most in automobile production, mainly for the manufacture of the driver's cabin and car of truck The vehicle body of case, car and minibus.Automobile cold-rolled sheet metal quality requirement is high, should have good surface quality to ensure zero Part appearance looks elegant, there is less thickness deviation to meet the requirement of Sheet Metal Forming Technology, while steel plate there should be good punching performance To go out complex-shaped part.

The content of the invention

In view of this, the present invention provides a kind of cold rolled automobile sheet and preparation method thereof.

The present invention provides a kind of cold rolled automobile sheet, and its chemical composition includes by weight percentage：

C：0.01~0.05%, Si：0.01~0.04%, Mn：0.10~0.50%, P≤0.02%, S≤0.01%, N ≤ 0.004%, O≤0.003%, Al：0.015~0.035%, RE (Ce)：>=0.0010%, remaining is iron and other can not keep away The impurity exempted from.

Further, the deep drawability of the cold rolled automobile sheet is：R values 1.8~2.5, n values 0.19~0.25.

The present invention also provides a kind of preparation method of above-mentioned cold rolled automobile sheet, and it includes：It is former by hot rolling of low-carbon continuous casting billet Material, hot rolling, cold rolling, bell-type annealing and smooth are carried out successively.

Further, slab heating temperature is 920~1160 DEG C, and the heat time is 0.5h~1h.

Further, the hot rolling uses the frame hot continuous rolling of CSP production lines 7,1010~1130 DEG C of hot rolling start rolling temperature, end 870~920 DEG C of temperature is rolled, 530~590 DEG C of coiling temperature, the thickness of steel plate is 2.0~5.0mm.

Further, the cold rolling is specially：By 5 frame cold continuous rollings after pickling, total reduction is 70~90%；It is described Bell-type annealing is specially：Coil of strip after cold rolling is 80% nitrogen and 20% hydrogen bell-type annealing furnace annealing through protective gas, annealing Temperature is 650~710 DEG C.

Further, the smooth reduction ratio is 0.8~3.0%.

Compared with prior art, silicon in cold rolled automobile slab provided by the invention, phosphorus are containing relatively low, and O, N content are relatively low, production Product have excellent deep drawability.

Brief description of the drawings

In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing There is the required accompanying drawing used in technology description to be briefly described.

Fig. 1 is the metallographic structure figure of steel plate prepared by the embodiment of the present invention 1.

Embodiment

The invention discloses a kind of cold rolled automobile sheet and preparation method thereof, those skilled in the art can be used for reference in this paper Hold, be suitably modified technological parameter realization.In particular, all similar replacements and change are to those skilled in the art For be it will be apparent that they are considered as being included in the present invention.The method of the present invention and application are by preferably implementing Example is described, related personnel substantially can not depart from present invention, in spirit and scope to method described herein and Using being modified or suitably change with combining, to realize and using the technology of the present invention.

Preferably, the cold rolling is specially：By 5 frame cold continuous rollings after pickling, total reduction is 70~90%；The cover Formula is annealed：Coil of strip after cold rolling is 80% nitrogen and 20% hydrogen bell-type annealing furnace annealing through protective gas, annealing temperature Spend for 650~710 DEG C.

Preferably, the smooth reduction ratio is 0.8~3.0%.

The preparation method is that using low-carbon continuous casting billet as hot rolling raw material, the frame hot continuous rolling of CSP production lines 7,5 are carried out It is frame cold continuous rolling, bell-type annealing, smooth, finally give the Automobile Plate of excellent deep drawability.

With reference to embodiment, the present invention is expanded on further：

Embodiment 1

The chemical composition of continuous casting billet is as shown in table 1：

Continuous casting billet chemical composition (the unit of table 1：%)

Embodiment	C	Si	Mn	P	S	Al	O	N	RE(Ce)
										1	0.025	0.015	0.140	0.008	0.004	0.23	0.0020	0.0028	0.0015

Continuous casting steel billet uses roller hearth type heating furnace, and heating-up temperature is 1110 DEG C, heat time 0.6h.Hot rolling start rolling temperature 1080 DEG C, 885 DEG C of finishing temperature.565 DEG C of coiling temperature, after 7 frame hot continuous rollings, the thickness of steel plate is 4.0mm；5 machine after pickling Frame cold continuous rolling, using 75% cold rolling total reduction, coil of strip after cold rolling is 80% nitrogen and 20% hydrogen cover through protective gas Formula anneal, annealing temperature are 670 DEG C, are cooled to after room temperature and carry out smooth, smooth reduction ratio 0.85%, are then produced Product deep drawability is tested, and it is as shown in the table 2 for test result, and the product metallographic structure is as shown in Figure 1.

The product deep drawability of table 2

Embodiment 2

The chemical composition of continuous casting billet is as shown in table 3：

Continuous casting billet chemical composition (the unit of table 3：%)

Embodiment	C	Si	Mn	P	S	Al	O	N	RE(Ce)
										2	0.020	0.014	0.120	0.006	0.003	0.24	0.0015	0.0020	0.0025

Continuous casting steel billet uses roller hearth type heating furnace, and heating-up temperature is 1130 DEG C, heat time 0.7h.Hot rolling start rolling temperature 1100 DEG C, 890 DEG C of finishing temperature.575 DEG C of coiling temperature, after 7 frame hot continuous rollings, the thickness of steel plate is 3.5mm；5 machine after pickling Frame cold continuous rolling, using 80% cold rolling total reduction, coil of strip after cold rolling is 80% nitrogen and 20% hydrogen cover through protective gas Formula anneal, annealing temperature are 685 DEG C, are cooled to after room temperature and carry out smooth, smooth reduction ratio 0.90%, are then produced Product deep drawability is tested, and test result is as shown in table 4.

The product deep drawability of table 4

Described above is only the preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art For member, under the premise without departing from the principles of the invention, some improvements and modifications can also be made, these improvements and modifications also should It is considered as protection scope of the present invention.

Claims

1. a kind of cold rolled automobile sheet, it is characterised in that its chemical composition includes by weight percentage：

C：0.01~0.05%, Si：0.01~0.04%, Mn：0.10~0.50%, P≤0.02%, S≤0.01%, N≤ 0.004%, O≤0.003%, Al：0.015~0.035%, RE (Ce)：>=0.0010%, remaining is iron and other are inevitable Impurity.

2. cold rolled automobile sheet according to claim 1, it is characterised in that the deep drawability of the cold rolled automobile sheet is：R values 1.8~2.5, n value 0.19~0.25.

3. the preparation method of the cold rolled automobile sheet described in claim 1, it is characterised in that including：Using low-carbon continuous casting billet as hot rolling Raw material, hot rolling, cold rolling, bell-type annealing and smooth are carried out successively.

4. preparation method according to claim 3, it is characterised in that slab heating temperature is 920~1160 DEG C, during heating Between be 0.5h~1h.

5. preparation method according to claim 3, it is characterised in that the hot rolling is connected using the frame of CSP production lines 7 heat Roll, 1010~1130 DEG C of hot rolling start rolling temperature, 870~920 DEG C of finishing temperature, 530~590 DEG C of coiling temperature, the thickness of steel plate For 2.0~5.0mm.

6. preparation method according to claim 3, it is characterised in that the cold rolling is specially：It is cold by 5 frames after pickling Tandem rolling, total reduction are 70~90%；The bell-type annealing is specially：Coil of strip after cold rolling through protective gas be 80% nitrogen and 20% hydrogen bell-type annealing furnace annealing, annealing temperature are 650~710 DEG C.

7. preparation method according to claim 3, it is characterised in that the smooth reduction ratio is 0.8~3.0%.