阅读说明：本技术 一种带镀层变厚度钢板的生产工艺 (Production process of variable-thickness steel plate with coating ) 是由 熊斐 李山青 汪义如 于 2019-03-22 设计创作，主要内容包括：本发明公开了一种带镀层变厚度钢板的生产工艺,包括先将等厚热轧/冷轧钢卷经过连续变厚度轧制后,获得连续变厚度冷轧钢卷,再将连续变厚度冷轧钢卷送至连续真空镀机组进行真空涂镀,获得带镀层的连续变厚度钢卷,最后交付用户；或先将等厚热轧/冷轧钢卷经过连续变厚度轧制后,获得连续变厚度冷轧钢卷,再将连续变厚度冷轧钢卷进行热处理,然后将热处理后的连续变厚度冷轧钢卷送至连续真空镀机组进行真空涂镀,获得带镀层的连续变厚度钢卷,最后交付用户。本发明能够避免现有技术方法均存在的问题,高效、经济地获得带镀层的变厚度钢卷。(The invention discloses a production process of a variable-thickness steel plate with a coating, which comprises the steps of firstly, continuously changing the thickness of a hot-rolled/cold-rolled steel coil with the same thickness to obtain a continuously variable-thickness cold-rolled steel coil, then conveying the continuously variable-thickness cold-rolled steel coil to a continuous vacuum plating unit for vacuum coating to obtain the continuously variable-thickness steel coil with the coating, and finally delivering the continuously variable-thickness steel coil to a user; or the constant-thickness hot-rolled/cold-rolled steel coil is continuously rolled in variable thickness to obtain a continuously variable-thickness cold-rolled steel coil, the continuously variable-thickness cold-rolled steel coil is subjected to heat treatment, the continuously variable-thickness cold-rolled steel coil subjected to heat treatment is sent to a continuous vacuum plating unit for vacuum coating to obtain the continuously variable-thickness steel coil with the coating, and finally the continuously variable-thickness steel coil is delivered to a user. The method can avoid the problems of the prior art and efficiently and economically obtain the variable-thickness steel coil with the coating.)

1. The production process of the variable-thickness steel plate with the coating is characterized by comprising the following steps of: comprises that

Firstly, continuously variable-thickness rolling is carried out on an equal-thickness hot-rolled/cold-rolled steel coil to obtain a continuously variable-thickness cold-rolled steel coil, then the continuously variable-thickness cold-rolled steel coil is sent to a continuous vacuum plating unit for vacuum coating to obtain a continuously variable-thickness steel coil with a plating layer, and finally the continuously variable-thickness steel coil is delivered to a user; or

The method comprises the steps of firstly, continuously changing the thickness of a hot-rolled/cold-rolled steel coil with the same thickness to obtain a continuously variable-thickness cold-rolled steel coil, then carrying out heat treatment on the continuously variable-thickness cold-rolled steel coil, then sending the continuously variable-thickness cold-rolled steel coil after the heat treatment to a continuous vacuum plating unit for vacuum coating to obtain the continuously variable-thickness steel coil with a plating layer, and finally delivering the continuously variable-thickness steel coil to a user.

2. The process for producing a coated variable thickness steel sheet as claimed in claim 1, wherein: after the continuous variable-thickness steel coil with the coating is obtained, the steel coil can be subjected to a leveling procedure and finally delivered to a user.

3. The process for producing a coated variable thickness steel sheet as claimed in claim 1, wherein: the heat treatment is continuous annealing treatment or cover annealing treatment.

4. The process for producing a coated variable thickness steel sheet as claimed in claim 3, wherein: the heat treatment is cover annealing treatment, and then a steel coil needs to be leveled.

5. The process for producing a coated variable thickness steel sheet as claimed in claim 1, wherein: the continuous vacuum plating unit comprises an inlet vacuum lock, a pretreatment chamber, a vacuum deposition chamber, an outlet preparation chamber and an outlet vacuum lock.

6. The process for producing a coated variable thickness steel sheet as claimed in claim 5, wherein: the vacuum deposition chamber adopts a physical vapor deposition mode.

7. The process for producing a coated variable thickness steel sheet as claimed in claim 6, wherein: the physical vapor deposition mode is thermal evaporation or ion plating.

Technical Field

The invention relates to a production technology of a variable-thickness steel plate, in particular to a production process of a variable-thickness steel plate with a coating.

Background

In order to reduce carbon emission, it is required to reduce the weight of an automobile as much as possible while securing strength, and continuously variable thickness steel sheets have been accepted by users due to their unique advantages and are increasingly demanded. For the purpose of corrosion protection, it is necessary to subject the continuously variable thickness steel sheet to a coating treatment. There are several treatment methods at present:

1) coating the coiled strip steel by a hot-dip or electroplating unit:

as in patent publication No. CN103806029A, after the thickness-variable rolling, the strip is subjected to electroplating, after which an alloying treatment is carried out, after which the user is submitted to a forming treatment. In the patent publication No. CN102712961, hot-rolled incoming materials are subjected to unequal-thickness rolling, then recrystallization annealing, electroplating and alloying treatment are carried out.

2) The coated equal-thickness strip steel is subjected to thickness-variable rolling to obtain the strip steel with the coating layer with the variable thickness:

for example, in patent publication No. CN101796210B, hot-rolled strip steel is hot-dip galvanized or hot-dip aluminized, then continuously rolled in variable thickness, and then the sheet material required by the user is cut from the coil as required. In contrast, U.S. Pat. No. US8522586B2 proposes hot-dipping or electroplating of a hot-rolled or cold-rolled incoming material, followed by unequal-thickness rolling and subsequent processing.

3) After the strip steel is cut or blanked, the cut (blanked) steel plate is subjected to single-piece electroplating treatment.

However, the above treatments have their own disadvantages:

firstly, whether electroplating or hot-dip plating is carried out, the requirement of unit control on the thickness uniformity of strip steel is high, namely the distance between an air knife and the strip steel during hot-dip plating directly influences the thickness of a plating layer, and if the thickness of the strip steel changes frequently and the thickness difference is large, the thickness of the plating layer is likely to be uneven; during electroplating, if the lengths of all equal-thickness sections of the strip steel are short and the thickness difference between the equal-thickness sections is large, the conductive roller can frequently jump, and the risk of burning the conductive roller is brought.

Secondly, the method of coating a single steel sheet is inefficient, costly and also affected by the size of the bath.

Furthermore, if the coating is applied and then rolled, the rolling process will damage the surface of the coating, which reduces the corrosion protection effect of the material.

Finally, there is often user feedback that the hydrogen embrittlement probability of the strip coating thickened plate after hot forming is higher than that of a strip coating equal-thickness plate, which is probably caused by the intrusion of hydrogen elements introduced during electroplating and hot-dipping into the strip steel substrate through the coating damaged during rolling.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a production process of a variable-thickness steel plate with a coating, which can avoid the problems of the prior art and efficiently and economically obtain the variable-thickness steel coil with the coating.

In order to achieve the purpose, the invention adopts the following technical scheme:

a production process of a variable-thickness steel plate with a coating comprises the following steps:

firstly, continuously variable-thickness rolling is carried out on an equal-thickness hot-rolled/cold-rolled steel coil to obtain a continuously variable-thickness cold-rolled steel coil, then the continuously variable-thickness cold-rolled steel coil is sent to a continuous vacuum plating unit for vacuum coating to obtain a continuously variable-thickness steel coil with a plating layer, and finally the continuously variable-thickness steel coil is delivered to a user; or

The method comprises the steps of firstly, continuously changing the thickness of a hot-rolled/cold-rolled steel coil with the same thickness to obtain a continuously variable-thickness cold-rolled steel coil, then carrying out heat treatment on the continuously variable-thickness cold-rolled steel coil, then sending the continuously variable-thickness cold-rolled steel coil after the heat treatment to a continuous vacuum plating unit for vacuum coating to obtain the continuously variable-thickness steel coil with a plating layer, and finally delivering the continuously variable-thickness steel coil to a user.

After the continuous variable-thickness steel coil with the coating is obtained, the steel coil can be subjected to a leveling procedure and finally delivered to a user.

The heat treatment is continuous annealing treatment or cover annealing treatment.

The heat treatment is cover annealing treatment, and then a steel coil needs to be leveled.

The continuous vacuum plating unit comprises an inlet vacuum lock, a pretreatment chamber, a vacuum deposition chamber, an outlet preparation chamber and an outlet vacuum lock.

The vacuum deposition chamber uses a physical Vapor deposition (PVD for short) mode, and can be thermal evaporation (resistance, induction heating or electron beam heating) plating or ion plating (cathode arc or magnetron sputtering).

The production process of the steel plate with the coating and with the variable thickness can conveniently solve the production problem of the steel plate with the coating and with the variable thickness, can efficiently obtain the steel coil with the uniform coating and with the variable thickness, and also avoids introducing hydrogen in the coating process and increasing the risk of hydrogen embrittlement. Meanwhile, the invention is not sensitive to the thickness change of the strip steel in the process, can obtain a more uniform coating, adopts the process of rolling first and then coating, prevents the coating from being damaged, and ensures that the strip steel has excellent anti-corrosion performance. In addition, the invention is deposited in a vacuum mode, no extra chemical is added, zero emission can be realized, the invention has great environmental protection advantage, no hydrogen element is introduced in the coating process, and the risk of hydrogen embrittlement in the later period is reduced.

Drawings

FIG. 1 is a flow chart of the production process of the present invention;

FIG. 2 is a schematic view of a continuous variable thickness cold rolled steel coil according to an embodiment of the present invention;

FIG. 3 is a schematic view of a second continuous variable thickness cold rolled steel coil according to an embodiment of the present invention.

Detailed Description

The technical scheme of the invention is further explained by combining the drawings and the embodiment.

Referring to fig. 1, the process for producing a plated variable thickness steel sheet according to the present invention includes:

1) continuously variable-thickness cold-rolled steel coils are obtained by continuously variable-thickness rolling the hot-rolled pickling coils or the cold-rolled steel coils with the same thickness, namely the strip steel has periodic thickness variation in the rolling direction;

2) carrying out heat treatment on the continuously variable-thickness cold-rolled steel coil, wherein the heat treatment mode can be continuous annealing or cover annealing;

3) flattening the steel coil subjected to the cover annealing treatment;

4) sending the flattened continuous variable-thickness steel coil into a continuous vacuum plating unit for vacuum coating (PVD, also called physical vapor deposition) to obtain a continuous variable-thickness steel coil with a plating layer;

5) according to the requirements of users, the continuous variable-thickness steel coil after vacuum plating can be selected to be leveled or uneven and then directly delivered to the users.

The steps are the technological process of producing the coating variable-thickness steel coil, and according to the actual situation, the continuously variable-thickness cold-rolled steel coil which is subjected to heat treatment or the continuously variable-thickness hard-rolled steel coil which is not subjected to heat treatment can be directly selected as the raw material to be sent into a continuous vacuum plating unit for coating treatment.