CN107868965B - A method of for controlling chromium plating surface of steel plate amount of chromium oxide - Google Patents

A method of for controlling chromium plating surface of steel plate amount of chromium oxide Download PDF

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CN107868965B
CN107868965B CN201610851832.3A CN201610851832A CN107868965B CN 107868965 B CN107868965 B CN 107868965B CN 201610851832 A CN201610851832 A CN 201610851832A CN 107868965 B CN107868965 B CN 107868965B
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chromium
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steel plate
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chrome
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CN107868965A (en
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李秀军
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Baoshan Iron and Steel Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00—Electroplating: Baths therefor
    • C25D3/02—Electroplating: Baths therefor from solutions
    • C25D3/04—Electroplating: Baths therefor from solutions of chromium
    • C25D3/08—Deposition of black chromium, e.g. hexavalent chromium, CrVI
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/10—Electroplating with more than one layer of the same or of different metals
    • C25D5/12—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/18—Electroplating using modulated, pulsed or reversing current
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D9/00—Electrolytic coating other than with metals
    • C25D9/04—Electrolytic coating other than with metals with inorganic materials

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  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Electroplating And Plating Baths Therefor (AREA)
  • Electroplating Methods And Accessories (AREA)

Abstract

The present invention provides a kind of method for improving chromium plating surface of steel plate amount of chromium oxide, include the following steps: 1), the control of cold rolling chromium plating base plate surface roughness；2) cleaning treatment, is carried out to cold-rolled substrate using alkali cleaning and acid cleaning process；3) technology controlling and process, is carried out to cold-rolled substrate surface metal chrome layer；4), chrome plating surface quality is modified；5) regeneration treatment, is carried out to chrome plating surface oxidation layers of chrome.

Description

A method of for controlling chromium plating surface of steel plate amount of chromium oxide
Technical field
The present invention relates to the production control technologies of chromium plating steel plate, in particular to the chrome plating granule surface contral skill of high oxidation chromium content (the high oxidation chromium content referred in the application is often referred to chrome plating surface oxidation chromium content in 15mg/m to art2More than).This method is related to Once cold rolling chrome plating is not suitable for secondary cold-rolling product.
Background technique
Currently, chrome plating occupies an important position in packaging fields such as crown plug, four spiral covers, drawn can and top bottom covers.Plating Cold-reduced sheet is mainly carried out cathodic reduction by the production principle of chromium plate (abbreviation TFS) in chromic anhydride aqueous solution, in steel plate table The product of face formation one layer of crome metal and chromium hydrous oxide film.Chromium plating steel plate comes across the U.S. sea mattress thatch at the beginning of the fifties earliest The chromic acid impregnation steel plate of industrial group's invention and the electrolytic phosphate of United States Steel Corporation's invention handle steel plate.Nineteen fifty-five day This starts to study electrolysis chromic acid processing, and by 1961, the tin free steel sheet that steel plate company, Japan is known as " extra large Top " entered Industrialized production.Then, iron company, Yawata and iron company, Fuji successively also develop chrome plating.Into the seventies, Japanese chromium Type TFS is understood by US and European, and starts to export to various countries.The production history of external chrome plating is more than 30 years existing, The demand of the developed countries such as the U.S., Japan, Britain, France and Germany is in ascendant trend in recent years.Such as: U.S.'s demand is about Account for the 30% of tin plate, 45% or more, Europe has accounted for 15%-25% for Japan, and China's chrome plating consumption figure only account for it is tin plating 7% or so of plate aggregate consumption.Chrome plating still belongs to the starting stage in China, domestic originally to only have Baosteel tin plate factory and wide Guangdong and Zhangzhou, Fujian uniformly produce chrome plating in mountain in east.In the recent period, many private enterprises are also in the production for greatly developing chrome plating.
Chrome plating is generally made of substrate, metallic chromium layer, the aqua oxidation nitride layer of chromium and 4 layers of oil film.Metal chrome plating is pressed JIS standard regulation name thickness of coating is generally 70mg/m2, producer's general control is in 100mg/m2Left and right, the hydrous oxide of chromium Film general control is in 7~20mg/m2Left and right.The electrodeposited chromium unit of tin plate factory, Baogang Stocks Trading Co. is first chromium plating unit of Baosteel, It is also that the country is fastest, specification is most thin, the state-of-the-art chrome plating of technique (TFS) special production line at present.The electrodeposited chromium unit It is able to produce the chrome plating that maximum width is 1050mm, with 200,000 tons/year of production capacity, unit selects " two-step method " work Skill and fluoride type plating solution.Since chromium plating in September, 2007 unit operation, plating ferrochrome product gradually puts goods on the market.Due to The knowledge for lacking chromium plating technical aspect, after product puts goods on the market, chromium plating plate surface exposes many mass defects (as become rusty Erosion, plate face jaundice, corrosion resistance difference etc.), certainly, other enterprises similarly face these problems at home.This is mainly due to platings Chromium plate coating surface there are discontinuous micro-pore defect, influence product service life and stored food and drink it is intrinsic Quality.Especially in moist, offshore area, along with transport turn around time is longer, (point rust lacks chrome plating surface quality problems Fall into) exposure it is more prominent.Since chromium oxide layer has dead-end pore, the work of chrome plating corrosion resistance of surface and covering with paint property can be improved With.Therefore, chromeplated product quality can be improved by improving chrome plating surface oxidation chromium content, have important practical significance.In addition, with Using chrome plating as the fast development of the overlay film iron product of substrate, the technical requirements of high oxidation chromium content chrome plating are equally proposed.
Currently, Baogang Stocks Trading Co.'s chrome plating product surface amount of chromium oxide is higher compared with other domestic producer's chromium plating panel products, It is controllable to 11~13.5mg/m2.Although the control of current amount of chromium oxide, which meets most of user, requires and produces control mark Standard, i.e., oxide layers of chrome thickness control is in 7~20mg/m2Left and right, but for applying in hot humid area and outlet in east The chrome platings user such as South Asia area, the problem that the status that chrome plating surface oxidation chromium content is relatively low and uniformity is poor mainly exposes are The corrosion resistance of chrome plating is poor, is also easy to produce a rust defect；There is also using chrome plating as its surface organic film of the film-covered iron of substrate simultaneously The deficiencies of binding force is poor.From the point of view of chrome plating product analysis or user feedback, chrome plating surface oxidation chromium content reaches 15mg/m2More than And ensure uniformly, could effectively guarantee the preferable corrosion resistance product quality requirement of chrome plating.
And for improving for chromium plating surface of steel plate amount of chromium oxide, influence factor is more complicated, not only includes that plating solution is joined Number, process conditions, while the control problem of the surface topography of cold-rolled substrate also to chromium plating surface of steel plate amount of chromium oxide and its uniformly Property has and significantly influences.Application No. is 200910053847.5 and 201110006936.1 Chinese patent Shens in the prior art It please disclose two and be related to the application of chrome plating the relevant technologies, primarily focus on chrome plating plating solution composition and chrome-plated process item Part is not directed to the control of surface oxidation chromium content.
Summary of the invention
Technical problem to be solved by the present invention lies in provide one kind can effectively control chromium plating surface of steel plate amount of chromium oxide Method.
Its technical problem to be solved can be implemented by the following technical programs.
A method of for improving chromium plating surface of steel plate amount of chromium oxide, include the following steps:
1), the control of cold rolling chromium plating base plate surface roughness is 0.3, Rz≤1.5 μm, Rsm >=190 μm in Ra；
2) cleaning treatment, is carried out to cold-rolled substrate using alkali cleaning and acid cleaning process；
It 3) include, the metal chromium solution of chromic anhydride, fluoboric acid ammonia, sulfoacetic acid and ammonium fluoride as plating solution, control using ingredient Bath temperature processed is 1.1~1.5,15~35A/dm of current density in 35~55 DEG C, pH value2；Obtain metallic chromium layer be 80~ 100mg/m2, chromium oxide layer thickness be 20~30mg/m2Chrome plating；
4) surface quality modification, is carried out to the chrome plating that step 3) obtains, includes specially chromic anhydride, hydrofluoric acid using ingredient Solution is modified as surface quality with the oxidation chromium solution of sulfuric acid, controls surface modification of liquor quality solution temperature at 40~45 DEG C；It obtains Obtaining chromium oxide layer thickness is 5~8mg/m2Chrome plating；
5) regeneration treatment, is carried out to chrome plating surface oxidation layers of chrome；Specifically: chromic anhydride, Potassiumiodate, ammonia are included using ingredient The oxidation chromium solution of guanidine-acetic acid and ammonium fluoride controls bath temperature at 25~35 DEG C as plating solution, and pH value is 1.7~2.1, electric current Density is in 1~10A/dm2；Acquisition chromium oxide layer thickness is 15~25mg/m2Chrome plating.
As the preferred embodiment of the present invention, the content of chromic anhydride described in the step 3) plating solution is 100~150g/L, institute The content for stating fluoboric acid ammonia is 3~7g/L, and the content of the sulfoacetic acid is 0.5~2.5g/L, the content of the ammonium fluoride is 3 ~7g/L.
Equally one of as the preferred embodiment of the present invention, the content of chromic anhydride described in the step 4) plating solution is 10~ 20g/L, the content of the hydrofluoric acid are 0.5~1.5g/L, and the content of the sulfuric acid is 0.1~0.5g/L.It is furthermore preferred that described The content of chromic anhydride is 12~18g/L, and the content of the hydrofluoric acid is 0.8~1.3g/L, the content of the sulfuric acid is 0.2~ 0.4g/L。
Also as one of the preferred embodiment of the present invention, the content of chromic anhydride described in the step 5) plating solution is 35~60g/ L, the content of the Potassiumiodate are 2~6g/L, and the content of the amion acetic acid is 1~3g/L, the content of the ammonium fluoride is 1~ 5g/L。
As the further improvement of the technical program, the pH value of the plating solution utilizes H2SO4Or ammonium hydroxide is adjusted.
As the further improvement of the technical program, using skin pass mill group rate-determining steps 1) in the surface it is thick Rugosity；Wherein working roll roller diameter be 410~460mm, roll-force be 2000~4000KN, work roll surface hardness be Hs 93~ 97, roll surface hardness is Hs 81~85, the processing of working roll electric spark.
Further, the grinding roller scheme of the working roll electric spark processing is roll main shaft gyration 25~30rpm/min of speed, Balladeur train transverse shifting 75~85mm/min of speed, 2.0~2.4A of discharge peak currents, pulse current ON 2.5~2.7ms of time, Pulse current 2.5~3.5ms of OFF time, charging voltage 100V, gap voltage 45V, servo voltage benchmark -6.9, servo gain 1, the roughness of corresponding roll is controlled in Ra 0.8-1.8 μm, Rz≤2.6 μm, Rsm >=230 μm.Preferably, corresponding roll is thick Rugosity is controlled at 0.9~1.5 μm of Ra.
Also further, the planisher entrance unit tension force of the skin pass mill group is in 13~16kg/mm2, intermediate and go out Mouth unit tension control is in 18~25kg/mm2；Deformation rate is controlled 0.5~3%.Preferably, deformation rate control 1~ 2%.
The method for controlling chromium plating surface of steel plate amount of chromium oxide by adopting the above technical scheme has following beneficial to effect Fruit:
1, the control based on grinding roller technology and smooth technology proposes and is suitble to do amount of chromium oxide cold rolling plating chrome substrate Surface characteristic control technology；
2, crome metal plating solution environmentally protective, at low cost, to can be recycled is developed, is ensuring the same of metallic chromium layer thickness When, improve chrome plating surface oxidation chromium content；
3, chromium oxide plating solution environmentally protective, at low cost, to can be recycled is developed, chrome plating surface oxidation chromium is improved Amount, 13~25mg/m of control range2, it is obvious to reduce mass defects incidence, the economic benefits such as chromium plating surface of steel plate point rust.
Detailed description of the invention
Fig. 1 is that roller surface pattern duplicates schematic diagram；
The chromium plating substrate topography that Fig. 2 is rolled for the new grinding roller technology of the present invention；
Fig. 3 is the surface topography of high oxidation chromium content chrome plating of the present invention and its compares with common chrome plating pattern；Fig. 3 includes 4 width attached drawings, wherein Fig. 3 a-1 and Fig. 3 a-2 is chrome plating surface topography of the present invention and its energy spectrum analysis；Fig. 3 b-1 and Fig. 3 b-2 is Conventional chromate plate surface pattern and its energy spectrum analysis；
Fig. 4 is that high oxidation chromium content chrome plating of the present invention and common chrome plating corrosion resistance compare；Wherein upper row is present invention plating Chromium plate, lower row are common chrome plating；
Fig. 5 is that high oxidation chromium content chrome plating of the present invention and common chrome plating electrochemistry compare.
Specific embodiment
Specific embodiments of the present invention are described in further detail with reference to the accompanying drawing.
The present invention is intended to provide a kind of method for controlling chromium plating surface of steel plate amount of chromium oxide, wherein plating mechanism and steel Plate surface defect Crack cause is in combination with following statement:
Electroplating process chromium ion receives electronics in electrode surface and becomes Adsorption of Chromium atom, there is electric discharge portion, theoretical draw comprehensively Two kinds of viewpoints of theory of discharging.At plating initial stage, if matrix surface is smooth (i.e. concave-convex few), surface-discharge is uniform, is at this time complete Face electric discharge, chromium is in matrix surface while forming core；And matrix surface is when occurring obvious uneven, surface-discharge collection neutron is convex Position is played, is at this time shelf depreciation, chromium is in the preferential forming core in the position of surface bulge.The exactly effect of current spike effect, makes It obtains coating at spike to thicken comparatively fast, valley portions thicken relatively slow.With the increase of electroplating time, the steel matrix surface of different roughness It the continuous forming core of chromium and grows up.While coating thickens, the difference in height between peak valley is also increasing, and coating surface is further thick It is rough.Be presented as in chrome-plated process " deep recess " rolling line can not deposited plating layer, cause cold-reduced sheet surface metal layers of chrome and oxidation Layers of chrome is unevenly distributed, and thereby reduces the corrosion resistance of chromium plating surface of steel plate, is caused the more quality of chromium plating surface of steel plate and is lacked It falls into, such as point rust, pore, " boiling " discoloration.
According to the basic control technology of belt steel flating technique, the rolling line of chromium plating substrate surface " bumps " injustice is mainly logical It crosses to duplicate during the rolling process by the roll of frosting treatment in advance and arrives surface of steel plate, the surface topography of roll determines steel plate Surface topography.Fig. 1 is the copying process schematic diagram of steel plate roll and surface of steel plate pattern during the rolling process.When with certain pressure When lower amount rolls, roller surface convex peak is squeezed into surface of steel plate under the action of draught pressure, makes surface of steel plate metal in short-term It is interior to reach yield limit, and local plastic deformation occurs.According to the principle of constancy of volume in theory of plastic strain in matrix, surface of steel plate Metal under squeezing action to roll groove position swell, form the convex peak of surface of steel plate.The surface topography of roll in this way is logical It crosses the relationship reversely duplicated and copies to surface of steel plate, form the surface topography with similar structure, the i.e. rolling of " bumps " injustice Line.Therefore, the main grinding for considering roll of surface topography control, rolling depressing force, roller matching and the replacement of chrome substrate are plated The factors such as period.
For substrate surface characteristics control, its surface roughness Ra is not only determined, but also Rpc and Rz determine rolling The depth of the number at peak and rolling line, prior Rsm determine unevenness in the operation of rolling in the process, this affects plating solution Wetability.Based on this, the invention proposes new grinding roller modes to determine the control skill of cold rolled surface pattern in conjunction with rolling mill practice Art, and then control the uniformity of chrome plating surface oxidation layers of chrome distribution.
It is main according to Faraday's law for the control of chrome plating surface oxidation chromium content:
G=KQ=Kit
Wherein, G is the quality of precipitating metal；K is proportionality constant (electrochemical equivalent)；Q be by electricity；I is that electric current is strong Degree；T is conduction time.
Improving chrome plating surface oxidation chromium content, there are two types of approach: first is that improving current strength；Second is that extending electroplating time.It is right In improving current strength, chromium oxide is improved mainly by way of increasing current density in scene under the conditions of high current density Amount easily leads to plate face or edge is turned to be yellow, and the neighbouring Tin Free Steel of cold-rolled substrate rolling line is unevenly distributed, etc..When for extending plating Between, it is mainly realized by way of lowering speed of production, but this influences the production efficiency of chrome plating again.
Faraday's law is combined with produced on-site speed, plate face width and current efficiency, current strength I can be write as
In above formula, I is total current (A)；G is theoretical Tin Free Steel (mg/m2)；V is process section speed (m/min)；W is that plate is wide (mm)；C is chromium electrochemical equivalent=52.01/6 (g/F)；η is cathode efficiency.
It follows that improving current efficiency under conditions of current strength is certain, can also be improved Tin Free Steel.Based on this, Another important feature of the present invention is to consider to change plating solution composition, adds environmentally protective additive, improves electroplating process electric current effect Rate, and then improve the amount of chromium oxide of chromium plating plate surface, develops novel chrome-plated process condition, so provide layers of chrome be evenly distributed, The chromium plating surface of steel plate control technology of high oxidation chromium content.
The purpose of the present invention can be realized by following measures:
The first step is cold rolling chromium plating base plate surface roughness control technology:
1) it, in order to make belt steel surface have preferable quality horizontal, is produced using skin pass mill group, using working roll roller Diameter is 410~460mm；Roll-force is 2000~4000KN, and work roll surface hardness is Hs 93~97, roll surface hardness For Hs 81~85, the processing of working roll electric spark.
2), electric spark grinding roller scheme be roll main shaft gyration 25~30rpm/min of speed, balladeur train transverse shifting speed 75~ 85mm/min, 2.0~2.4A of discharge peak currents, pulse current ON 2.5~2.7ms of time, pulse current OFF time 2.5~ 3.5ms, charging voltage 100V, gap voltage 45V, servo voltage benchmark -6.9V, servo gain 1, corresponding roll it is coarse Degree can be controlled in Ra 0.8-1.8 μm, preferably 0.9~1.5 μm of Rz≤2.6 μm Ra (vertical rolling direction), Rsm >=230 μm (the distance between peak of profile top line and valley line).
3), planisher entrance unit tension force is in 13~16kg/mm2, intermediate and exporting unit's tension force 18~ 25kg/mm2.According to skin pass mill group maximum distortion ability, deformation rate is designed as 0.5~3%.
Based on above-mentioned process control technology, it is ensured that cold-rolled substrate surface roughness meets following parameter: roughness Ra 0.3~ 0.6 μm, Rz≤1.5 μm (vertical rolling direction), Rsm >=190 μm (the distance between peak of profile top line and valley line).
Second step is to carry out cleaning treatment to cold-rolled substrate using conventional alkali cleaning and acid cleaning process, obtains surface-active ratio Higher cold-rolled steel sheet substrate.Cleaning section first passes through alkali cleaning later through overpickling, this is to remove belt steel surface dirt and mention High belt steel surface activity.
Third step is cold-rolled substrate surface metal chrome layer process control technology: using crome metal solution composition chromic anhydride (CrO3) 100~150g/L, fluoboric acid ammonia (NH4BF4) 3~7g/L, sulfoacetic acid (C2H4O5S) 0.5~2.5g/L, ammonium fluoride (NH4F) 3~7g/L controls 35~55 DEG C of bath temperature, and pH value (uses H for 1.1~1.52SO4Or ammonium hydroxide is adjusted), electric current 15~35A/dm of density2；Obtain 80~100mg/m of metallic chromium layer2, 20~30mg/m of chromium oxide layer thickness2Chrome plating.
4th step is chrome plating surface quality modification technique: using chromium oxide solution composition for chromic anhydride (CrO3) 10~20g/ L (preferably 12~18g/L), 0.5~1.5g/L of hydrofluoric acid (preferably 0.8~1.3g/L), 0.1~0.5g/L of sulfuric acid (preferably 0.2 ~0.4) 40~45 DEG C of bath temperature, are controlled.Acquisition surface-brightening, the uniform chrome plating of coating, i.e. metallic chromium layer 80~ 100mg/m2, 5~8mg/m of chromium oxide layer thickness2。
5th step is chrome plating surface oxidation layers of chrome regeneration techniques: using chromium oxide solution composition chromic anhydride (CrO3) 35~ 60g/L, Potassiumiodate (KIO3) 2~6g/L, amion acetic acid (NH2CH2COOH) 1~3g/L, ammonium fluoride (NH4F) 1~5g/L, control 25~35 DEG C of bath temperature processed, pH value (uses H for 1.7~2.12SO4Or ammonium hydroxide is adjusted), 25~35 DEG C of bath temperature are controlled, electricity 1~10A/dm of current density2.Obtain surface-brightening, coating uniformly, the chrome plating of excellent corrosion resistance and high oxidation chromium content, i.e. metal 80~100mg/m of layers of chrome2, 15~25mg/m of chromium oxide layer thickness2。
The production process of normal chrome plating, simultaneously, surface oxidation layers of chrome is also with growth for the generation of surface metal layers of chrome.This Outside, since crome metal section plating solution acidity is stronger, etch chrome plating surface oxidation layers of chrome, i.e., chromium oxide layer is equally along with molten Solution.Moreover, it is larger in the fluctuation of crome metal section current density, cause chromium oxide layer presence more porous.Therefore, from crome metal Duan Sheng The chrome plating that output is come is poor in terms of surface quality, glossiness.Based on this, in above-mentioned steps, the technical program is in metal Chromium section plating solution adds fluoboric acid ammonia (NH4BF4) 3~7g/L and sulfoacetic acid (C2H4O5S) 0.5~2.5g/L additive improves electricity Bath pH value and coating deposition current efficiency reduce the current density of crome metal section deposition, are meeting metallic chromium layer deposition Meanwhile foring the preferable chromium oxide layer of quality.Using chrome plating surface quality modification technique, i.e., modified using solution composition Crome metal section surface quality and glossiness, wherein 0.5~1.5 g/L of solution composition hydrofluoric acid and 0.1~0.5g/L of sulfuric acid effect To dissolve the undesirable oxidation chrome plating of crome metal section surface；Guarantee the binding force of subsequent oxidation chromium section coating surface.Also, in order to The chrome plating of high oxidation chromium content, the uniform excellent corrosion resistance of coating is obtained, the technical program also proposed chrome plating surface oxidation Layers of chrome regeneration techniques pass through Potassiumiodate (KIO3) 2~6g/L and amion acetic acid (NH2CH2COOH) 1~3g/L additive, into one The current efficiency that step improves chrome-plating process obtains the chromium oxide layer of low porosity under the conditions of low current density.
Technology implementation path of the invention is strip after cold rolled annealed, using even fashion to belt steel surface roughness And pattern is controlled, and the chrome plating of high oxidation chromium content is formed by plating unit.The present invention is considering that cold-rolled substrate surface is special In the case where levying influence problem, cold rolled surface roughness control technology and novel electroplating technology skill are targetedly proposed Art, under identical alkali cleaning, acid washing conditions, that develops high oxidation chromium content rolls chromium plating surface of steel plate control technology.Hereinafter, passing through More specific embodiment is illustrated.
Embodiment 1:
The present embodiment controls chromium plating surface of steel plate amount of chromium oxide using following specific steps:
(1), electric spark grinding roller mode controls the surface physical characteristic of roll: roll main shaft gyration speed 27rpm/min, sliding Frame transverse shifting speed 85mm/min, discharge peak currents 2.0A, pulse current ON time 2.6ms, pulse current OFF time 3.0ms, charging voltage 100V, gap voltage 45V, servo reference -6.9V, servo gain 1, corresponding 2# breast roller it is thick Rugosity can be controlled in 1.2 μm of Ra, Rz=2.5 μm (vertical rolling direction), Rsm=241 μm (peak of profile top line and valley line it Between distance).
(2), control cold-rolled substrate surface physical characteristic: produced using skin pass mill group, use working roll roller diameter for 430mm；Roll-force is 3000KN, and work roll surface hardness is Hs 94, and roll surface hardness is Hs 85, working roll electric spark Processing.Planisher entrance unit tension force is in 15kg/mm2, intermediate and exporting unit's tension force is in 20kg/mm2.According to flat Complete machine group maximum distortion ability, deformation rate are designed as 2%.
Based on above-mentioned process control technology, it is ensured that cold-rolled substrate surface roughness meets following parameter: 0.35 μ of roughness Ra M, Rz=1.2 μm (vertical rolling direction), Rsm=201 μm (the distance between peak of profile top line and valley line) cold to get arriving Roll substrate NO.1 (surface topography is as shown in Figure 2).
(3), cleaning treatment is carried out to cold-rolled substrate using conventional alkali cleaning and acid cleaning process, it is relatively high obtains surface-active Cold-rolled steel sheet substrate NO.2, surface Residual oil residual iron amount < 0.5mg/m2。
(4), crome metal section electroplating solution, i.e. chromic anhydride (CrO are configured3) additional amount 110g/L, fluoboric acid ammonia (NH4BF4) be added Measure 5g/L, sulfoacetic acid (C2H4O5S) additional amount 1.0g/L, ammonium fluoride (NH4F) additional amount 3.5g/L；Using Conventional heaters, 40 DEG C of bath temperature of control, pH value are 1.3 (being adjusted with ammonium hydroxide), and current density is controlled in 20A/dm2；Cold-rolled substrate NO.2 is set Enter metal chromium plating bath processing time 7s, can get metallic chromium layer 95mg/m2, chromium oxide layer thickness 22mg/m2Chrome plating NO.3。
(5), configuration chrome plating surface quality modifies solution, i.e. chromic anhydride (CrO3) additional amount 15g/L, hydrofluoric acid 1.0g/L, Sulfuric acid 0.3g/L；Using Conventional heaters, 42 DEG C of solution temperature are controlled；It will be in chrome plating NO.3 merging surface quality modification solution Time 2s is handled, can get surface-brightening, coating uniform chrome plating NO.4, i.e. metallic chromium layer 94mg/m2, chromium oxide layer thickness 7mg/m2。
(6), configuration chrome plating surface oxidation layers of chrome regenerates plating solution, i.e. chromic anhydride (CrO3) additional amount 50g/L, Potassiumiodate (KIO3) additional amount 3g/L, amion acetic acid (NH2CH2COOH) additional amount 2g/L, ammonium fluoride (NH4F) additional amount 1g/L；Using normal Heater is advised, controls 27 DEG C of bath temperature, pH value is 1.9 (being adjusted with ammonium hydroxide), and current density control is 3A/dm2.By chrome plating NO.4 is placed in chromium oxide layer regeneration plating solution and handles time 2s, can get uniform surface-brightening, coating, excellent corrosion resistance and hyperoxia Change the chrome plating NO.5, i.e. metallic chromium layer 97mg/m of chromium content2, chromium oxide layer thickness 22mg/m2。
It is chrome plating surface topography of the present invention and its energy spectrum analysis as shown in Fig. 3 a-1 and 3a-2 and following table 1；
Table 1:
It is conventional chromate plate surface pattern and its energy spectrum analysis as shown in Fig. 3 b-1 and Fig. 3 b-2 and following table 2；
Table 2:
(7), damp heat test and electrochemical analysis are carried out for the chrome plating NO.5 of high oxidation chromium content, embodied preferable Corrosion resistance, as shown in figure 4, the corrosion resistance comparison of the chrome plating and common chrome plating (choosing Baosteel chrome plating) obtained for the present invention As a result, it can thus be appreciated that the corrosion resistance for the chrome plating that the present invention obtains is preferable.
As shown in figure 5, the electrochemistry comparison diagram of the high oxidation chromium content chrome plating and common chrome plating obtained for the present invention.From In figure can, it is evident that the high oxidation chromium content chrome plating that the present invention obtains corrosion potential than common chrome plating corrosion potential more Just, this illustrates that the high oxidation chromium content chrome plating that the present invention obtains has corrosion resistance more better than common chrome plating.
Embodiment 2:
The present embodiment controls chromium plating surface of steel plate amount of chromium oxide using following specific steps:
(1), electric spark grinding roller mode controls the surface physical characteristic of roll: roll main shaft gyration speed 28rpm/min, sliding Frame transverse shifting speed 80mm/min, discharge peak currents 2.3A, pulse current ON time 2.6ms, pulse current OFF time 3.3ms, charging voltage 100V, gap voltage 45V, servo voltage benchmark -6.9V, servo gain 1, corresponding 2# breast roller Roughness can be controlled in 1.6 μm of Ra, Rz=2.3 μm (vertical rolling direction), Rsm=253 μm of (peak of profile top line and the lowest point The distance between line).
(2), control cold-rolled substrate surface physical characteristic: produced using skin pass mill group, use working roll roller diameter for 450mm；Roll-force is 3500KN, and work roll surface hardness is Hs 95, and roll surface hardness is Hs 83, working roll electric spark Processing.Planisher entrance unit tension force is in 14.5kg/mm2, intermediate and exporting unit's tension force is in 22kg/mm2.According to Skin pass mill group maximum distortion ability, deformation rate are designed as 1.5%.
Based on above-mentioned process control technology, it is ensured that cold-rolled substrate surface roughness meets following parameter: 0.5 μ of roughness Ra M, Rz=1.3 μm (vertical rolling direction), Rsm=210 μm (the distance between peak of profile top line and valley line) cold to get arriving Roll substrate NO.1.
(3), cleaning treatment is carried out to cold-rolled substrate using conventional alkali cleaning, acid cleaning process, it is relatively high obtains surface-active Cold-rolled steel sheet substrate NO.2, surface Residual oil residual iron amount < 0.5mg/m2。
(4), crome metal section electroplating solution, i.e. chromic anhydride (CrO are configured3) additional amount 140g/L, fluoboric acid ammonia (NH4BF4) be added Measure 6g/L, sulfoacetic acid (C2H4O5S) additional amount 2g/L, ammonium fluoride (NH4F) additional amount 6g/L；Using Conventional heaters, control 50 DEG C of bath temperature, pH value is 1.35 (being adjusted with ammonium hydroxide), and current density is controlled in 30A/dm2；Cold-rolled substrate NO.2 is placed in Metal chromium plating bath handles time 7s, can get metallic chromium layer 92mg/m2, chromium oxide layer thickness 27mg/m2Chrome plating NO.3.
(5), configuration chrome plating surface quality modifies solution, i.e. chromic anhydride (CrO3) additional amount 17g/L, hydrofluoric acid 1.3g/L, Sulfuric acid 0.4g/L；Using Conventional heaters, 43 DEG C of solution temperature are controlled；It will be in chrome plating NO.3 merging surface quality modification solution Time 2s is handled, can get surface-brightening, coating uniform chrome plating NO.4, i.e. metallic chromium layer 90mg/m2, chromium oxide layer thickness 6.5mg/m2。
(6), configuration chrome plating surface oxidation layers of chrome regenerates plating solution, i.e. chromic anhydride (CrO3) additional amount 45g/L, Potassiumiodate (KIO3) additional amount 4g/L, amion acetic acid (NH2CH2COOH) additional amount 2.4g/L, ammonium fluoride (NH4F) additional amount 2g/L；Using Conventional heaters control 30 DEG C of bath temperature, and pH value is 2.0 (being adjusted with ammonium hydroxide), and current density control is 5A/dm2.By chromium plating Plate NO.4 is placed in chromium oxide layer regeneration plating solution and handles time 2s, can get uniform surface-brightening, coating, excellent corrosion resistance and height The chrome plating NO.5 of amount of chromium oxide, i.e. metallic chromium layer 92mg/m2, chromium oxide layer thickness 20mg/m2。
Embodiment 3:
The present embodiment controls chromium plating surface of steel plate amount of chromium oxide using following specific steps:
(1), electric spark grinding roller mode controls the surface physical characteristic of roll: roll main shaft gyration speed 26rpm/min, sliding Frame transverse shifting speed 78mm/min, discharge peak currents 2.2A, pulse current ON time 2.6ms, pulse current OFF time 2.8ms, charging voltage 100V, gap voltage 45V, servo voltage benchmark -6.9V, servo gain 1, corresponding 2# breast roller Roughness can be controlled in 1.0 μm of Ra, Rz=2.0 μm (vertical rolling direction), Rsm=261 μm of (peak of profile top line and the lowest point The distance between line).
(2), control cold-rolled substrate surface physical characteristic: produced using skin pass mill group, use working roll roller diameter for 420mm；Roll-force is 2500KN, and work roll surface hardness is Hs 95, and roll surface hardness is Hs 84, working roll electric spark Processing.Planisher entrance unit tension force is in 14kg/mm2, intermediate and exporting unit's tension force is in 21kg/mm2.According to flat Complete machine group maximum distortion ability, deformation rate are designed as 1.0%.
Based on above-mentioned process control technology, it is ensured that cold-rolled substrate surface roughness meets following parameter: 0.4 μ of roughness Ra M, Rz=1.1 μm (vertical rolling direction), Rsm=223 μm (the distance between peak of profile top line and valley line) cold to get arriving Roll substrate NO.1.
(3), cleaning treatment is carried out to cold-rolled substrate using conventional alkali cleaning, acid cleaning process, it is relatively high obtains surface-active Cold-rolled steel sheet substrate NO.2, surface Residual oil residual iron amount < 0.5mg/m2。
(4), crome metal section electroplating solution, i.e. chromic anhydride (CrO are configured3) additional amount 130g/L, fluoboric acid ammonia (NH4BF4) be added Measure 4g/L, sulfoacetic acid (C2H4O5S) additional amount 1.5g/L, ammonium fluoride (NH4F) additional amount 4g/L；Using Conventional heaters, control 45 DEG C of bath temperature processed, pH value is 1.25 (being adjusted with ammonium hydroxide), and current density is controlled in 25A/dm2；Cold-rolled substrate NO.2 is set Enter metal chromium plating bath processing time 7s, can get metallic chromium layer 85mg/m2, chromium oxide layer thickness 25mg/m2Chrome plating NO.3。
(5), configuration chrome plating surface quality modifies solution, i.e. chromic anhydride (CrO3) additional amount 13g/L, hydrofluoric acid 0.8g/L, Sulfuric acid 0.2g/L；Using Conventional heaters, 41 DEG C of solution temperature are controlled；It will be in chrome plating NO.3 merging surface quality modification solution Time 3s is handled, can get surface-brightening, coating uniform chrome plating NO.4, i.e. metallic chromium layer 83mg/m2, chromium oxide layer thickness 6mg/m2。
(6), configuration chrome plating surface oxidation layers of chrome regenerates plating solution, i.e. chromic anhydride (CrO3) additional amount 40g/L, Potassiumiodate (KIO3) additional amount 5g/L, amion acetic acid (NH2CH2COOH) additional amount 1.6g/L, ammonium fluoride (NH4F) additional amount 3g/L；Using Conventional heaters control 31 DEG C of bath temperature, and pH value is 1.9 (being adjusted with ammonium hydroxide), and current density control is 7A/dm2.By chromium plating Plate NO.4 is placed in chromium oxide layer regeneration plating solution and handles time 2s, can get uniform surface-brightening, coating, excellent corrosion resistance and height The chrome plating NO.5 of amount of chromium oxide, i.e. metallic chromium layer 95mg/m2, chromium oxide layer thickness 18mg/m2。

Claims (11)

1. a kind of method for improving chromium plating surface of steel plate amount of chromium oxide, which comprises the steps of:
1), the control of cold rolling chromium plating base plate surface roughness is 0.3, Rz≤1.5 μm, Rsm >=190 μm in Ra；
2) cleaning treatment, is carried out to cold-rolled substrate using alkali cleaning and acid cleaning process；
It 3) include, the metal chromium solution of chromic anhydride, fluoboric acid ammonia, sulfoacetic acid and ammonium fluoride as plating solution, control plating using ingredient Liquid temperature is 1.1~1.5,15~35A/dm of current density in 35~55 DEG C, pH value2；Acquisition metallic chromium layer is 80~100mg/ m2, chromium oxide layer thickness be 20~30mg/m2Chrome plating；
4) surface quality modification, is carried out to the chrome plating that step 3) obtains, includes specially chromic anhydride, hydrofluoric acid and sulphur using ingredient The oxidation chromium solution of acid modifies solution as surface quality, controls surface modification of liquor quality solution temperature at 40~45 DEG C；Obtain oxygen Change layers of chrome with a thickness of 5~8mg/m2Chrome plating；
5) regeneration treatment, is carried out to chrome plating surface oxidation layers of chrome；Specifically: chromic anhydride, Potassiumiodate, amino second are included using ingredient The oxidation chromium solution of acid and ammonium fluoride is used as plating solution, and control bath temperature is at 25~35 DEG C, and pH value is 1.7~2.1, current density In 1~10A/dm2；Acquisition chromium oxide layer thickness is 15~25mg/m2Chrome plating.
2. the method for improving chromium plating surface of steel plate amount of chromium oxide according to claim 1, which is characterized in that the step 3) content of chromic anhydride described in plating solution is 100~150g/L, and the content of the fluoboric acid ammonia is 3~7g/L, the sulfoacetic acid Content be 0.5~2.5g/L, the content of the ammonium fluoride is 3~7g/L.
3. the method according to claim 1 or claim 2 for improving chromium plating surface of steel plate amount of chromium oxide, which is characterized in that described The pH value of plating solution utilizes H2SO4Or ammonium hydroxide is adjusted.
4. the method according to claim 1 or claim 2 for improving chromium plating surface of steel plate amount of chromium oxide, which is characterized in that described The content of chromic anhydride described in step 4) plating solution is 10~20g/L, and the content of the hydrofluoric acid is 0.5~1.5g/L, the sulfuric acid Content be 0.1~0.5g/L.
5. the method for improving chromium plating surface of steel plate amount of chromium oxide according to claim 4, which is characterized in that the chromic anhydride Content be 12~18g/L, the content of the hydrofluoric acid is 0.8~1.3g/L, and the content of the sulfuric acid is 0.2~0.4g/L.
6. the method according to claim 1 or claim 2 for improving chromium plating surface of steel plate amount of chromium oxide, which is characterized in that described The content of chromic anhydride described in step 5) plating solution is 35~60g/L, and the content of the Potassiumiodate is 2~6g/L, the amion acetic acid Content be 1~3g/L, the content of the ammonium fluoride is 1~5g/L.
7. the method according to claim 1 or claim 2 for improving chromium plating surface of steel plate amount of chromium oxide, which is characterized in that use Skin pass mill group rate-determining steps 1) in the surface roughness；Wherein working roll roller diameter is 410~460mm, and roll-force is 2000~4000KN, work roll surface hardness are Hs 93~97, and roll surface hardness is Hs 81~85, working roll electric spark Processing.
8. the method for improving chromium plating surface of steel plate amount of chromium oxide according to claim 7, which is characterized in that the work Roller electric spark processing grinding roller scheme be roll main shaft gyration 25~30rpm/min of speed, balladeur train transverse shifting speed 75~ 85mm/min, 2.0~2.4A of discharge peak currents, pulse current ON 2.5~2.7ms of time, pulse current OFF time 2.5~ 3.5ms, charging voltage 100V, gap voltage 45V, servo voltage benchmark -6.9V, servo gain 1, the roughness control of corresponding roll System is in Ra 0.8-1.8 μm, Rz≤2.6 μm, Rsm >=230 μm.
9. the method for improving chromium plating surface of steel plate amount of chromium oxide according to claim 8, which is characterized in that corresponding roll Roughness control at 0.9~1.5 μm of Ra.
10. the method for improving chromium plating surface of steel plate amount of chromium oxide according to claim 7, which is characterized in that described flat The planisher entrance unit tension force of complete machine group is in 13~16kg/mm2, intermediate and exporting unit's tension force 18~ 25kg/mm2；Deformation rate is controlled 0.5~3%.
11. the method for improving chromium plating surface of steel plate amount of chromium oxide according to claim 10, which is characterized in that the change Form quotient is controlled 1~2%.
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