JPS6089594A - Tin plate for welded and painted can and its production - Google Patents

Abstract

PURPOSE:To provide a titled tin plate which can expand thoroughly an adequate current range for welding with the tin plate coated with less tin and has good welding workability by forming an Sn layer via an alloy layer having prescribed content of Sn contg. an Fe-Sn crystal on the surface of a black plate. CONSTITUTION:The surface of a black plate such as a low carbon steel plate or the like is subjected to primary tin plating to cause crystal alloying and thereafter the black plate is subjected to a light rolling down treatment like skin pass. The crystal alloying treatment is performed suitably by utilizing the continuous annealing line. The surface of the steel sheet subjected to the light rolling down treatment is electrolytically pickled and is then subjected to secondary tin plating to form 0.1-0.9g/m<2> tin layer via 0.05-0.9g/m<2> alloy layer in terms of tin content on the surface of the steel plate. The secondary tin plating is formed preferably by an electroplating method. The tin plate for a welded and painted can having 100A adequate current range for welding by a copper wire type seam welding method at 400Hz frequency after painting and baking for >=10min at 170-230 deg.C is thus obtd.

Description

[Detailed description of the invention]

The present invention relates to a tin plate for welded painted cans and a method for manufacturing the same.
As a tinplate for welded cans such as canned goods, it is possible to sufficiently expand the appropriate welding current range using tinplate with a small amount of tin, thus producing welded cans with good industrial welding workability and a low defect rate. The purpose of this invention is to provide a furiki that can be used as a furiki and a preferable method for producing the same. The use of tin-plated steel sheets (tin plate) to produce welded cans for cans, etc. has been widely practiced, but recently, thinned steel sheets with a reduced amount of tin plating (Lightly Tin) have been widely used. Coated 5t
EEL 5HEET (hereinafter referred to as LTS) is being put into practical use for such purposes. That is, compared to conventional tinplate (tin plating amount of about 241/i or more),
Is that tin plated tl f /n? Since the tin plate material is reduced in size or less, and the amount of expensive tin consumed is significantly reduced, the desired welded can for painting can be obtained at low cost. However, when manufacturing cans with welded coatings using such LTS materials, it is clear that the appropriate welding current range is extremely narrow or non-existent44, that is, such welding is possible without peeling. There is a limiting current value (hereinafter referred to as IB) that does not cause φl ml' when bonding is performed (a predetermined bonding strength or higher), and on the other hand, there is a limiting current value (hereinafter referred to as IB) that does not cause expulsion (i.e., no expulsion occurs). The limiting current value (hereinafter referred to as IA) is also important;
It is preferable that it is below. In other words, the difference (IA'-
IB ampere) is the appropriate welding current range, and IA
- It is possible to perform stable and high-quality welding with a culm with a large IBO value, but in the LTS material mentioned above, the amount of unalloyed tin remaining after the paint baking in the can manufacturing process is extremely large. This IA-IBO value must be extremely small because it remains in small amounts or not at all, and in some cases it often becomes a negative value. Welding is often done at the expense of one of the relationships. In other words, the appropriate welding current range (CIA-IB) is industrially 100% under the conditions of the copper wire seam welding method with a frequency of 400H2.
It is said that an amperage of 7 or more is preferable, but in the case of the above-mentioned LTS rate, it is extremely common for paint burning to become lower than that later, which naturally requires the management of welding sales, which is a crossroads, and moreover, the actual In factories, there are large fluctuations in current moxibustion conditions, etc., and especially when IA-IB is negative as mentioned above, welding must be performed at the expense of peelability or collapse due to spatter. The invention was devised after repeated studies in view of the above-mentioned circumstances, and it was created with Fexsny (However, X
0805 to 0.9 f
0.1 to 0.9 through the alloy layer of /y+z'/+r
? We propose a tin coating for welded cans that is characterized by the formation of a tin layer, and the alloy layer is formed between the iron base and the tin layer during the glue flow after tin plating in conventional tin plate. Compared to the generated alloy (Fesn2), it is mainly composed of an alloy with a crystal structure with a high Fe content. As a manufacturing method for obtaining the tin plate for welded cans of the present invention as described above, the first method is the t2E plating method.
It can be appropriately obtained by secondary tin plating, crystallized alloying, light pressure treatment, electrolytic pickling, and secondary tin plating. After performing tin plating in an amount necessary to form a layer, this is subjected to crystal alloying treatment, and then subjected to light pressure treatment such as skin panu, and then electroplated with an amount of secondary tin plating corresponding to the above tin layer. Implementation by law. The above-mentioned crystal alloying treatment after the first tin plating can be carried out using a continuous annealing line as appropriate. That is, before continuous annealing, a predetermined amount of tin is applied by chemical plating, vapor phase plating, electroplating, etc. Crystal alloying can also be appropriately achieved by continuous annealing after primary tin plating, but it is of course possible to perform alloying treatment separately from such continuous annealing. be. In addition, by adopting a temperature north of 460℃ for this alloying treatment, Fern straddle F
eSn+Fe3 At least Fe is 8n like SnC
It has been confirmed that it is possible to obtain a crystalline alloy with an atomic ratio equal to or higher than that of the tin layer. A crystalline alloyed layer can be obtained. The crystal alloyed product as described above is then subjected to a light reduction such as a skin pass, and then a second tin plating is applied as a layer commensurate with the tin layer described above to improve formability as a can body. Although an excellent product is obtained, electrolytic pickling between such alloying treatment and the second tin plating is important for forming a stable tin layer.
Further, prior to this electrolytic pickling, electrolytic cleaning is performed as appropriate. That is, when an electrolytic spoon is also used, an alkaline cleaning solution such as sodium hydroxide is used for electrolytic cleaning under appropriately heated conditions to remove impurities on the surface of the alloyed layer formed. The electrolytic pickling carried out after this electrolytic cleaning uses a sulfuric acid solution of an appropriate concentration, but when used in combination in this way, the electrolytic cleaning is preferably carried out immediately before the electrolytic pickling. For this electrolytic cleaning, it is necessary to use electrolytic conditions in which the final bath is the cathode on the original plate side, and the tin plating layer formed by secondary tin plating after these treatments is strong and stable. It has been confirmed that it is formed on the surface of the alloyed layer, and a preferable tinplate for welded cans can be obtained. It is preferable to form the above-mentioned secondary tin-plated film by electroplating. ), but also E
It may be manufactured by reflow processing within the TL. As mentioned above, the crystal alloying treatment after the first plating is to crystallize the entire amount of plated tin, which easily forms an alloy crystallized layer with a precisely specified amount and a flat surface condition. Therefore, the interface with the tin layer by the subsequent secondary plating is also substantially flat, and in this way, the desired corrosion resistance and welding can be achieved with a relatively small amount of crystal alloyed layer and tin layer. You can enjoy sex together. When the crystalline alloyed material undergoes skinnosis or other treatments after the first plating, some cracks occur in the crystalline alloyed layer, and 2
The second plating tin layer will be formed by entering, but by pre-aging or undergoing flow treatment after the second plating, it will mainly enter the crystal alloyed layer by Δ1 and become the iron base. Alloying is achieved in the tin layer in close proximity to form an alloyed layer with excellent barrier effect. However, this kind of tinplate for cans is generally subjected to a process such as baking the paint during production (can manufacturing), and even with such baking, the above-mentioned In any case, silver paintings that are alloyed by reflow processing or baking, where a condition similar to that of flow processing is formed, are similar to conventional LT
The amount is small compared to S, and the boundary between the crystal alloyed layer and the tin layer is substantially flat. The (H) of the crystal alloyed layer is 0.05 f/m in order to effectively obtain the barrier effect while exposing the base iron.
0.055'/m' or more by forming an alloyed layer on the iron base surface in a dense and uniform coating state as described in 1 above. A barrier effect can be obtained. Also, the upper limit of this crystal alloyed layer is 0.9 f/n? Electrolytic cleaning was carried out in an alkaline cleaning solution at 80°C at a concentration exceeding this limit of 301/l under a cycle of 0.6 seconds at a current density of IOA/dm2, and this electrolyte cleaning was performed. After that the concentration is 30? 10/l in sulfuric acid solution
A pickling treatment was carried out for 0.6 seconds at a current density of A/d♂. The electrolytic cleaning was performed under the condition that the final bath was the cathode on the original plate side. Forming a crystalline alloy layer beyond the alloying treatment after the first tin plating as described above, followed by electrolytic cleaning and electrolytic pickling, not only increases the amount of expensive tin consumed but also involves various processing. We can see the cracks caused by time. Moreover, regarding the pure tin layer formed on top of this crystal alloyed layer, in order to maintain the unalloyed tin level after coating and firing at 0.08 f/m' or more, 0.1 f/- is the lower limit, and if the unalloyed tin after paint baking is less than o, osr/z, effective welding characteristics cannot be ensured. The upper limit of the tin layer is 9.9 f/i, and even if -12 pure tin layers are formed below this limit, in the present invention which is formed with a substantially flat U-shaped boundary surface as described above. In particular, there is no one that improves weldability or the like, which goes against the essence of the present invention, which has the basic purpose of reducing the amount of tin consumed. Specific examples according to the present invention will be described below along with comparative examples. A low carbon steel plate that was hot rolled, pickled, and then cold rolled to a thickness of 0.22 mm was washed with alkali to produce a C to 0.28 f/lrt.
', 0.22? /lr? and o, o9f/m' electrotin plating at 650°C. Continuous annealing with a soaking time of 20 seconds for alloying, followed by a skin bath with an elongation rate of 1.0%.Sodium hydroxide (NaOH) content of 60% is 0.49%.
f/rr? , 0.35 f/rr? and 0.3Fl
/rr? The second tin plating was carried out, and the thus obtained products were treated with glue flow at 250°C and those without treatment, respectively, and then chemically treated and coated with static oil to obtain products. That is, the amount of primary tin plating is 0.28f/rF? The material subjected to the reflow treatment at 0.49 f/ + A is the material of the present invention, and the material that is not reflowed is the material of the present invention, and the amount of the primary tin plating is 0.22. ri/d
The material that was subjected to the reflow treatment with a secondary tin plating pattern of 0.35 f/m' was called the invention material III, and the material that was not reflowed was called the invention material IV, and the amount of the first tin plating was 0.0'.
l/- and the amount of secondary tin plating is o, asf, /n? The material subjected to reflow treatment is designated as Invention Material (2), and the material that is not reflowed is designated as Invention Material v1. Also, the primary tin plating amount is 0.35 t/t and the secondary tin plating amount is 0.16 t/t.
t/n? , and the reflow-treated material is an invented material■

[
1) Flow 1p without treatment was designated as the invention material m. In addition, as a comparative example for these invention materials I~)■, as conventional I and TS materials, it was
LTSI-I plated with about 65r/yr/ of tin, treated with IJ flow treatment and without treatment, as well as IT+.
A #25 tin plate was also prepared as a comparative example. These inventive and comparative materials were then subjected to dry firing for 40 minutes at a furnace temperature of 200°C. In other words, this dry baking is equivalent to baking after painting, and the paint baking on this type of can material uses different paints on the inner and outer surfaces of the can body, and the specific type of paint used also depends on the type of paint being transported. Naturally, the baking temperature and time will differ, but in the present invention, the determination is typically made using the heat treatment conditions described above at 200°C for 40 minutes, and such determination results are Of course, when the baking temperature or time is varied as described above, the determination can be made by appropriately converting. However, using the inventive material and comparative material obtained as described above as materials, 100 cans each were welded using a copper wire two-seam welding machine with a frequency of 400 II z and an overlapping width set to 0.4 tone. Manufactured cans. In other words, the appropriate welding current range for the welding process as described above, the amount of iron released for measuring the barrier properties of the alloy layer, and the ATC (AI 1oy-Tin-Coup)
The test values (both before dry firing) are summarized as 3fA in Table 1 below. That is, in the present invention materials 1 to 2, the amount of tin used was 0.5 to 0.
．． 8 f/n? Although this is a very small amount, the appropriate current range for welding is 100A or more, and although it is narrower than 825A for #25 tin, 100A or more is industrially suitable for work. As mentioned above, it is possible to weld with good properties. Ratio MLTS material 20
It is clear that the weldability of the welding material is significantly better than that of A grade or negative weldability considering the amount of tin used. Also, iron elution under conditions where the alloy layer is exposed]W
1 m f/a/I ・20 hr
818: or less, and has a barrier property that is superior to all comparative materials including #25 tin wood at 1 m t /al・20 hr or more, and is also good in terms of ATc value etc.) It was confirmed that this was the case. In addition, the adhesion resistance of the tin plating layer of the above-mentioned example was evaluated by making 0 cuts at intervals of 1 mm in the shape of a base grain, applying Ericlen processing to this, and then performing a peel test using Nichiban Cellotape. Products manufactured by carrying out both electrolytic cleaning and electrolytic pickling before tin plating are found to have extremely stable and strong tin plating adhesion, with an average peeling rate of less than 1 inch for 20 pieces. confirmed. On the other hand, those that were subjected to electrolytic pickling only had a peeling rate of less than 2% on average of 20 pieces, and still had sufficient adhesion resistance. In addition, even if electrolytic cleaning is performed, if the final pass is on the original plate side, the peeling rate may be around 5°, and the tin plating resistance will be lower than when both electrolytic cleaning and electrolytic pickling are not performed. The wearing condition tends to deteriorate. According to the present invention as explained above, it is possible to secure a sufficiently expanded appropriate welding current range for tin plate with a significantly small amount of tin, thereby obtaining a desirable welded can with excellent industrial workability, and thus reducing the defective rate. This invention aims to manufacture cans with fewer welded coatings, has good iron elution resistance, and other properties, and is industrially very effective. Procedural amendments (0) Showa bi8.12 January 7th JPO Commissioner Shiga Half 1, Indication of the case Showa rI? Patent Application No. 190θ Otsu No. 2, invention
3. Relationship with the case of the person making the amendment Name of the applicant for the old license (Name) Japan Threat Management Company 4, Agent Showa Month, Day, Shipping As shown in the attached sheet: Contents of the amendment 11 The statement in the section "2 Claims" on pages 1-2 of Middle East of the present specification is corrected as follows. "] Through an alloy layer with a tin content of 0.05 to 0.9 g/m' containing crystals such as FexSny (where X > y) or crystals containing elements other than Fe on the surface of the steel plate. O01~0.9 g/m' of tin layer is formed, and at least 0.0 of unalloyed tin is formed on the painted baked iron.
8 jJ/m' or more of tinplate for welded cans, characterized in that it has a residual strength of 8 jJ/m' or more. 2. Copper & surface
Next, tin plating, and the width part is 0 on the surface of AfJ 1 plate.
．． 0.1-0.05-0.9.9/m' through the alloy layer.
Form a tin layer of 9 g/m', 170-230'0,1
Paint baking for 0 minutes or more (=frequency 400 Hz after J
The suitable welding voltage and current range using the copper wire type soma welding method is 1.
A manufacturing method for welded paint cans characterized by a capacity of 00 amperes or more. 3. Claim 2, ζ The bath-coated can use according to claim 2, in which prior to the electrolytic pickling treatment prior to secondary tinning, the final bath is chemically pickled with the steel plate side serving as a cathode. Shisa's manufacturing method. 2. In the fourth negative line of 5, the phrase ``on a different surface of the original plate'' is corrected to ``on the surface of the steel plate''. 3. Delete the word "crystal" in line 177 and 6-1, line 3, and line 6 of the same page. 4. In the 15th line of page 6, the phrase “1460°C” has been changed to “4.
96 'Oj. 5, same page 17-7 21] "Having an atomic ratio...
···· can. It has been confirmed that it is possible to obtain an alloy having crystals having an atomic ratio of D', and it is possible to obtain an extremely dense and flat surface in general of such an alloy layer. ”. 6.Delete "1-Crystal" in the negative 3rd line of the same 7.1
,'/, In line 13 of the same shell, correct the phrase ``1-Alkaline cleaning liquid'' to ``I Cleaning liquid containing alkali'' 3, 8,
In the 15th line of Dosei, 1-Alloyed layer surface' is corrected to read 'Alloy layer surface'. 9. In line 200 of the same page, the word "original plate" is corrected to read "I" steel plate. 10. Delete the word "crystal" in the 13th and 144th lines of the same page, page 9, and the second line of the same page. 11. In the 16th line of page 8, ``alloy crystallization J+'i J'' is corrected to ``alloy layer.'' 12, same page line 19, 9 negative line 8, line 177 and 200
The words "crystalline alloyed layer" in the lines are corrected to "alloy layer." 13. In the 10th line of page 9, the phrase “alloying) meeting” is replaced with “
"alloy layer". 14. 10th line 6th line γ12th line 3rd line: ``Matako...
``...No plating,'' should be corrected as follows. ``Also, the upper limit of this alloy layer is 0.9j?/m', and it is difficult to form an alloy layer exceeding this limit.
In addition to increasing the consumption of tin, cracks during processing were also observed. Furthermore, for the abacus tin layer formed on such an alloy layer, 0-1 jJ/m2 is required to maintain unalloyed tin of 0.0817'm or more after coating and baking. is the lower limit, and if the amount of unalloyed tin after paint burnout is less than 0.08 g/m2, effective welding characteristics cannot be ensured. Tin 1 So's 2nd period is 0-9j! /m', and even if two pure tin layers are formed beyond this limit, there will be a substantially flat boundary uIj as described above.
Among the products of the present invention formed using the above, there is nothing that particularly improves the bath contact property, etc., which is contrary to the present project of the present invention whose basic purpose is to reduce the cost of tin. Specific examples according to the present invention will be described below along with comparative examples. After hot-rolling, pickling, and cooling treatment, a low carbon steel sheet with a J'f'' of 0.22m+n is washed with alkali to give a strength of 0128g.
/m', 0.22 g/m' and 0.09 g/
m' each electro-tin plated, these are 650
'O. Continuous annealing with a soaking time of 20 seconds for alloying was performed, followed by a skin bath with an elongation rate of 1.0. Electrolytic cleaning treatment was carried out under current conditions of 0.6 second repetitions at a current density of /dm2, and after this electrolytic cleaning, the same < 1o A/' in a sulfuric acid solution with a concentration of 301/l
A cathodic pickling treatment was carried out for 0.6 seconds at a current density of 100 dm. Electrolytic cleaning and electrolytic pickling after alloying treatment of plated bales/O049g/m for small objects
The second tin plating was carried out at 0.35 g/m' and 0°38 g/m'. 16, page 16, lines 1-2, 1'', r I -III is...
It says "......" f U' I −
III is plated, L tin amount is on one side, kDO85~0.
-81/m2,” he corrected. 17. In the 3rd and 6th lines of page 17, correct the words ``r2o samples'' as ``F2o samples,'' respectively. 18. In the 9th line of the same page, the word "original plate" is corrected to read "1" steel plate.

Claims (1)

[Claims] 1. Tin content of 0.05 to 0.9 f/n, including crystals of FeχSny (where X≧y) or crystals obtained by adding elements in steel other than pe on the surface of the original plate? A tin layer of 0.1 to 9 t/- is formed through an alloy layer of 0.1 to 9 t/-, and the tin layer is baked so that at least 0.1 to 9 t/- of unalloyed tin is present. Ofl/-
A tin plate for welded cans, characterized in that a tin plate with a welded coating remains on the can. 2 The surface of the original plate is first tin-plated and then subjected to crystal alloying treatment, then subjected to light pressure treatment, then electrolytically pickled, and then subjected to secondary tin plating.
Next, tin plating the surface of the original plate with a tin content of 0.05.
0.1-0.9 through an alloy layer of ~0.92 ? /n
? A welding coating characterized by forming a tin layer and having a frequency of 400)Lz copper wire seam welding method with a suitable welding current range of 100 amperes or more after coating baking at 170 to 230°C for 10 minutes or more. Manufacturing method for tinplate for cans. 3. The method for producing tinplate for welded coated cans according to claim 2, wherein prior to the electrolytic pickling treatment, electrolytic cleaning is performed with the final bath serving as a cathode on the original plate side.