CN109750244A - A method of mitigating malleable cast iron galvanizing by dipping pasc reaction - Google Patents
A method of mitigating malleable cast iron galvanizing by dipping pasc reaction Download PDFInfo
- Publication number
- CN109750244A CN109750244A CN201910225606.8A CN201910225606A CN109750244A CN 109750244 A CN109750244 A CN 109750244A CN 201910225606 A CN201910225606 A CN 201910225606A CN 109750244 A CN109750244 A CN 109750244A
- Authority
- CN
- China
- Prior art keywords
- cast iron
- galvanizing
- malleable cast
- dipping
- minutes
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Coating With Molten Metal (AREA)
Abstract
The invention belongs to metal surface engineering fields, and in particular to a method of mitigate malleable cast iron galvanizing by dipping pasc reaction.The present invention uses concentration to be surface-treated for 25~35% aqueous hydrogen peroxide solution to mitis metal first, effectively mitigates the activity of silicon, and galvanizing by dipping operation is then carried out in 450~570 DEG C of Zn-0.05wt.%Al aluminium alloy.The uniformity that the present invention can reduce zinc-plated temperature, effectively reduce mitis metal thickness of coating and dramatically increase malleable casting thickness of coating.
Description
Technical field
The invention belongs to metal surface engineering field, in particular to a kind of mitigation malleable cast iron galvanizing by dipping pasc reaction
Method.
Background technique
Hot galvanizing malleable cast iron is mainly used in hot galvanizing pipe fitting, and hot galvanizing pipe fitting includes galvanized elbow, zinc-plated flange, plating
Zinc bend pipe, zinc-plated reduced pipe, zinc-plated pipe cap end socket.During hot-dip, complicated physics occurs for pipe fitting matrix and melting plating solution
With chemical reaction, corrosion resistant hard-packed zinc-iron alloys layer is formed.Alloy-layer combines together with pure zinc layer, iron matrix, therefore
Its corrosion resistance is strong.Hot galvanizing pipe fitting is plated mainly for delivery of the pipeline engineering such as coal gas, heating, such as steel pipe tube body
Zinc preservative treatment, connecting pipe will also carry out zinc-plated processing.
Studies have shown that existing in galvanizing by dipping obvious since the silicone content of mitis metal is higher (1.4~1.8%)
Pasc reaction, cause thickness of coating increase and thickness of coating it is uneven.Currently, malleable cast iron hot dip galvanizing process and external plating
There are apparent gaps for zinc technology, first is that the temperature drift of heat galvanizing liquid, generally at 600 DEG C or so, and external is 460 DEG C of left sides
It is right；Second is that the zinc coat of mitis metal is partially thick, thickness of coating uniformity is poor, and zinc consumption significantly increases.It is, in general, that plated can
It is lower to forge cast iron part carbon silicone content, and when surface quality of continuous castings is better, then zinc and iron it is easier in conjunction with and reduce zinc-plated temperature.
Conversely, then to use higher zinc-plated temperature, zinc-iron reaction aggravates at this time, and the iron in galvanizing flux increases, and forms cadmia, increases
The big viscosity of galvanizing flux, thus zinc coat is partially thick.Therefore, it is necessary to carry out surface preparation to mitis metal, mitigate plating
Pasc reaction during zinc, final realize reduce zinc-plated temperature, reduce thickness of coating and increase the mesh of thickness of coating uniformity
's.
Summary of the invention
The present invention designs a kind of method for mitigating malleable cast iron galvanizing by dipping pasc reaction, using certain density peroxide
Change aqueous solution of hydrogen and surface preparation is carried out to mitis metal, mitigates the activity of silicon, it is therefore an objective to reduce zinc-plated temperature, effectively reduce
Mitis metal thickness of coating, the uniformity for dramatically increasing malleable casting thickness of coating.
The technical scheme is that
The present invention uses concentration to carry out 50~70 minutes for 25~35% aqueous hydrogen peroxide solution to mitis metal
Casting after pretreatment is carried out alkali cleaning-washing-pickling-is washed-and helps plating-drying surface treatment, so by surface preparation
The galvanizing by dipping carried out in 450~570 DEG C of Zn-0.05wt.%Al alloy pond 3~5 minutes is immersed afterwards to handle, obtain thickness compared with
Thin and uniform malleable cast iron coating.The purpose of the present invention is reduce zinc-plated temperature, reduce thickness of coating and increase thickness of coating
Uniformity.
The specific treatment process of the surface treatment are as follows: the NaOH solution for the use of mass fraction being 15% is at 70~80 DEG C
Alkali cleaning 3 minutes, after clear water flushing pickling 3 minutes in the hydrochloric acid that mass fraction is 15%, at 70~80 DEG C after clear water flushing
Ingredient is NH containing 27g in 100ml water4Cl、23g ZnCl2、5g SnCl2、2g K2ZrF6Help and carried out in plating liquor 5 minutes
Plating is helped, it is 10 minutes dry at 100 DEG C after the completion.
It advanced optimizes, carrying out pretreated aqueous hydrogen peroxide solution concentration to malleable cast iron is 30%, when pretreatment
Between be 60 minutes.
It needs aqueous hydrogen peroxide solution to carry out the pretreatment of long period (preferably 60 minutes) to malleable cast iron surface, makes table
Element silicon in surface layer is selectively oxidized into silica, and forms concentration gradient from inside to outside, and poor silicon occurs in superficial layer, leads
It causes the activated silica of dissolved state to significantly reduce, has reached the activity and active purpose for reducing silicon, to greatly reduce pasc reaction
Generation, make that coating is relatively thin and coating is uniform.Using conventional surface treatment, alkali cleaning degreasing, pickling oxide layer, by oxygen
Change the silica inside layer to slough, is more advantageous to zinc-plated progress, plating leakage will not be generated, make that coating is relatively thin and coating is uniform.
It advanced optimizes, the temperature for carrying out hot galvanizing processing to malleable cast iron is 460~560 DEG C, the galvanizing by dipping time
It is 4 minutes.Zinc-plated temperature is substantially reduced, galvanizing time is reduced.
The principle of the present invention is as follows:
It is, in general, that silicone content all exists bright generally all 1.4~1.8% when carrying out galvanizing by dipping in malleable cast iron
Aobvious pasc reaction, therefore the activity for reducing mitis metal surface silicon help to obtain thin and uniform dip galvanized.It adopts
When carrying out surface preparation to mitis metal with aqueous hydrogen peroxide solution, due to the strong oxidizing property of hydrogen peroxide, make malleable casting
Element silicon in ironware superficial layer aoxidizes, and forms the lower SiO of activity2, can effectively reduce mitis metal surface silicon
Activity makes its pasc reaction in hot dip galvanizing process be effectively suppressed, can reduce zinc-plated temperature, effectively reduce zinc coat
Thickness, and increase the uniformity of coating.
Acquisition of technology effect of the invention is:
After carrying out surface preparation to malleable cast iron using certain density aqueous hydrogen peroxide solution, galvanizing by dipping can be reduced
Temperature, the uniformity for effectively reducing mitis metal thickness of coating and dramatically increasing malleable casting thickness of coating.
Detailed description of the invention
Fig. 1 is that the malleable cast iron sample for handling 60 minutes without aqueous hydrogen peroxide solution plates after 460 DEG C of progress hot galvanizings
The microstructure picture of layer.
Fig. 2 is to handle 60 minutes malleable cast iron samples coating after 460 DEG C of progress hot galvanizings through aqueous hydrogen peroxide solution
Microstructure picture.
Fig. 3 is that the malleable cast iron sample for handling 60 minutes without aqueous hydrogen peroxide solution plates after 510 DEG C of progress hot galvanizings
The microstructure picture of layer.
Fig. 4 is to handle 60 minutes malleable cast iron samples coating after 510 DEG C of progress hot galvanizings through aqueous hydrogen peroxide solution
Microstructure picture.
Fig. 5 is that the malleable cast iron sample for handling 60 minutes without aqueous hydrogen peroxide solution plates after 560 DEG C of progress hot galvanizings
The microstructure picture of layer.
Fig. 6 is to handle 60 minutes malleable cast iron samples coating after 560 DEG C of progress hot galvanizings through aqueous hydrogen peroxide solution
Microstructure picture.
Fig. 7 is that the malleable cast iron sample for handling 20 minutes by aqueous hydrogen peroxide solution plates after 460 DEG C of progress hot galvanizings
The microstructure picture of layer.
Specific implementation method
The present invention is described in further detail below with reference to embodiment:
Embodiment 1:
As reference galvanizing by dipping sample, the malleable cast iron that size is 10mm × 10mm is subjected to alkali cleaning-washing-
A series of processing of plating-drying are washed-are helped in pickling-, and hot dip galvanized zinc alloy liquid ingredient is Zn-0.05wt.%Al, zinc liquid temperature
Control immerses malleable cast iron sample in zinc liquid immersion plating 4 minutes at 460 DEG C.Quantitative metallographic analysis shows that malleable cast iron sample plates
Layer average thickness is 102 μm, and the thickness of coating difference of thickness and thinnest part is 148.6 μm.
1 malleable cast iron of table galvanized layer thickness (μm) after immersion plating 4 minutes in 460 DEG C of zinc liquid
In the present invention, concentration is used to carry out surface to the malleable cast iron of 10mm × 10mm for 30% aqueous hydrogen peroxide solution
Pretreatment 60 minutes, drying carries out alkali cleaning-washing-pickling-is washed-to it and helps a series of processing of plating-drying after taking-up,
Specific treatment process are as follows: using mass fraction be 15% NaOH solution at 70~80 DEG C alkali cleaning 3 minutes, clear water rinse after
Pickling 3 minutes in the hydrochloric acid that mass fraction is 15%, the ingredient after clear water flushing at 70~80 DEG C is to contain 27g in 100ml water
NH4Cl、23g ZnCl2、5g SnCl2、2g K2ZrF6Help in plating liquor and to carry out helping plating in 5 minutes, after the completion at 100 DEG C
Lower drying 10 minutes.Hot dip galvanized zinc alloy liquid ingredient is Zn-0.05wt.%Al, and zinc liquid temperature controls at 460 DEG C, then may be used
Cast iron coupon is forged to immerse in zinc liquid immersion plating 4 minutes.Quantitative metallographic analysis shows that malleable cast iron coating average thickness is 65.6 μm,
Reduce 35.7% than the coating average thickness without pretreating specimen.Thickness of coating difference between thickness and thinnest part is
83.2 μm, than reducing 44% without the thickness of coating between pretreating specimen thickness and thinnest part is poor, coating uniformity is obtained
To being obviously improved.
Embodiment 2:
As reference galvanizing by dipping sample, the malleable cast iron that size is 10mm × 10mm is subjected to alkali cleaning-washing-
A series of processing (processing step is same as Example 1) hot dip galvanized zinc alloy liquid ingredients of plating-drying are washed-are helped in pickling-
Zn-0.05wt.%Al, zinc liquid temperature control at 510 DEG C, malleable cast iron sample are immersed in zinc liquid immersion plating 4 minutes.Quantitative metallography
Analysis shows malleable cast iron sample coating average thickness is 108.6 μm, the thickness of coating difference of thickness and thinnest part is 101.7 μ
m。
2 malleable cast iron of table galvanized layer thickness (μm) after immersion plating 4 minutes in 510 DEG C of zinc liquid
In the present invention, concentration is used to carry out surface to the malleable cast iron of 10mm × 10mm for 30% aqueous hydrogen peroxide solution
Pretreatment 60 minutes, drying carries out alkali cleaning-washing-pickling-is washed-to it and helps a series of processing of plating-drying after taking-up
(processing step is same as Example 1).Hot dip galvanized zinc alloy liquid ingredient is similarly Zn-0.05wt.%Al, and zinc liquid temperature control exists
510 DEG C, then malleable cast iron sample is immersed in zinc liquid immersion plating 4 minutes.Quantitative metallographic analysis shows that malleable cast iron coating is average
With a thickness of 64.8 μm, reduce 40% than the coating average thickness without pretreating specimen.Plating between thickness and thinnest part
Layer thickness difference is 44.4 μm, than reducing 56.3% without the thickness of coating between pretreating specimen thickness and thinnest part is poor,
The improvement that coating uniformity is become apparent.
Embodiment 3:
As reference galvanizing by dipping sample, the malleable cast iron that size is 10mm × 10mm is subjected to alkali cleaning-washing-
A series of processing of plating-drying, (processing step is same as Example 1) are washed-help in pickling-.Hot dip galvanized zinc alloy liquid ingredient is
Zn-0.05wt.%Al, zinc liquid temperature control at 560 DEG C, malleable cast iron sample are immersed in zinc liquid immersion plating 4 minutes.Quantitative metallography
Analysis shows malleable cast iron sample coating average thickness is 163.8 μm, the thickness of coating difference of thickness and thinnest part is 267.6 μ
m。
3 malleable cast iron of table galvanized layer thickness (μm) after immersion plating 4 minutes in 560 DEG C of zinc liquid
In the present invention, concentration is used to carry out surface to the malleable cast iron of 10mm × 10mm for 30% aqueous hydrogen peroxide solution
Pretreatment 60 minutes, drying carries out alkali cleaning-washing-pickling-is washed-to it and helps a series of processing of plating-drying after taking-up
(processing step is same as Example 1).Hot dip galvanized zinc alloy liquid ingredient is similarly Zn-0.05wt.%Al, and zinc liquid temperature control exists
560 DEG C, then malleable cast iron sample is immersed in zinc liquid immersion plating 4 minutes.Quantitative metallographic analysis shows that malleable cast iron coating is average
With a thickness of 122.7 μm, reduce 25% than the coating average thickness without pretreating specimen.Plating between thickness and thinnest part
Layer thickness difference is 222.8 μm, than reducing 16.7% without the thickness of coating between pretreating specimen thickness and thinnest part is poor,
Coating uniformity has obtained certain improvement.
Comparative example 1:
As reference galvanizing by dipping sample, the malleable cast iron that size is 10mm × 10mm is subjected to alkali cleaning-washing-
A series of processing of plating-drying are washed-are helped in pickling-(step is same as Example 1).Hot dip galvanized zinc alloy liquid ingredient is Zn-
0.05wt.%Al, zinc liquid temperature control at 460 DEG C, malleable cast iron sample are immersed in zinc liquid immersion plating 4 minutes.Quantitative metallography point
Analysis shows that malleable cast iron sample coating average thickness is 102 μm, and the thickness of coating difference of thickness and thinnest part is 148.6 μm.
In the present invention, concentration is used to carry out surface preparation 20 minutes for 30% aqueous hydrogen peroxide solution to malleable cast iron
Afterwards, drying carries out alkali cleaning-washing-pickling-is washed-to it and helps a series of processing of plating-drying, step and implementation after taking-up
Example 1 is identical.Hot dip galvanized zinc alloy liquid ingredient is similarly Zn-0.05wt.%Al, and zinc liquid temperature is controlled at 460 DEG C, then will be malleable
Cast iron coupon immerses in zinc liquid immersion plating 4 minutes.Malleable cast iron coating average thickness is 90.5 μm, than the plating without pretreating specimen
Layer average thickness reduces 11.3%.Thickness of coating difference between thickness and thinnest part is 131.4 μm, than not preprocessed examination
Thickness of coating difference between sample thickness and thinnest part reduces 11.6%, and coating uniformity slightly improves, but significantly lower than real
Apply the effect of example 1.
4 malleable cast iron of table galvanized layer thickness (μm) after immersion plating 4 minutes in 460 DEG C of zinc liquid
Claims (4)
1. a kind of method for mitigating malleable cast iron galvanizing by dipping pasc reaction, it is characterised in that: use concentration for 25~35%
Aqueous hydrogen peroxide solution pre-process within 50~70 minutes to mitis metal, then by pretreated casting by being surface-treated
The galvanizing by dipping processing carried out in 450~570 DEG C of galvanized alloy pond 3~5 minutes is immersed afterwards, obtains thinner thickness and uniformly
Malleable cast iron coating.
2. mitigating the method for malleable cast iron galvanizing by dipping pasc reaction as described in claim 1, which is characterized in that the peroxide
The concentration for changing aqueous solution of hydrogen is 30%.
3. mitigating the method for malleable cast iron galvanizing by dipping pasc reaction as described in claim 1, which is characterized in that described malleable
Ironcasting pretreatment time in aqueous hydrogen peroxide solution is 60 minutes.
4. mitigating the method for malleable cast iron galvanizing by dipping pasc reaction as described in claim 1, which is characterized in that will pre-process
Casting afterwards carries out alkali cleaning-washing-pickling-is washed-and helps plating-drying surface treatment, then in 460~560 DEG C of Zn-
Galvanizing by dipping processing in 4 minutes is carried out in the pond 0.05wt.%Al.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910225606.8A CN109750244B (en) | 2019-03-25 | 2019-03-25 | Method for reducing reactivity of malleable cast iron hot dip galvanizing silicon |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910225606.8A CN109750244B (en) | 2019-03-25 | 2019-03-25 | Method for reducing reactivity of malleable cast iron hot dip galvanizing silicon |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109750244A true CN109750244A (en) | 2019-05-14 |
| CN109750244B CN109750244B (en) | 2020-09-08 |
Family
ID=66409156
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910225606.8A Active CN109750244B (en) | 2019-03-25 | 2019-03-25 | Method for reducing reactivity of malleable cast iron hot dip galvanizing silicon |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109750244B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110616392A (en) * | 2019-10-24 | 2019-12-27 | 常州大学 | Surface pretreatment method for improving quality of malleable cast iron hot-dip galvanizing coating |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05239606A (en) * | 1992-02-28 | 1993-09-17 | Kawasaki Steel Corp | Galvanizing method for high tensile strength steel sheet |
| JPH06207259A (en) * | 1993-01-11 | 1994-07-26 | Kawasaki Steel Corp | Manufacture of galvanized high tensile strength steel sheet |
| CN107142435A (en) * | 2017-06-23 | 2017-09-08 | 遵义鑫华源电力设备有限公司 | Power iron fitting hot dip galvanizing process |
-
2019
- 2019-03-25 CN CN201910225606.8A patent/CN109750244B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05239606A (en) * | 1992-02-28 | 1993-09-17 | Kawasaki Steel Corp | Galvanizing method for high tensile strength steel sheet |
| JPH06207259A (en) * | 1993-01-11 | 1994-07-26 | Kawasaki Steel Corp | Manufacture of galvanized high tensile strength steel sheet |
| CN107142435A (en) * | 2017-06-23 | 2017-09-08 | 遵义鑫华源电力设备有限公司 | Power iron fitting hot dip galvanizing process |
Non-Patent Citations (3)
| Title |
|---|
| 李智，等: "钢基热浸镀锌的研究", 《材料导报》 * |
| 涂浩，等: "硅对热浸镀ZnAl4合金镀层组织及生长动力学的影响", 《粉末冶金材料科学与工程》 * |
| 苏旭平，等: "热浸镀硅反应性研究", 《金属学报》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110616392A (en) * | 2019-10-24 | 2019-12-27 | 常州大学 | Surface pretreatment method for improving quality of malleable cast iron hot-dip galvanizing coating |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109750244B (en) | 2020-09-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108179418B (en) | Preparation method of zinc-nickel alloy coating structure suitable for strong corrosion environment | |
| CN109252125B (en) | Hot-dip galvanized aluminum-magnesium alloy coating and preparation method and application thereof | |
| US20110073484A1 (en) | Metal material with a bismuth film attached and method for producing same, surface treatment liquid used in said method, and cationic electrodeposition coated metal material and method for producing same | |
| CN102534449B (en) | Hot-dip galvanizing method for Q460 steel pipe | |
| CN102676981B (en) | Method for laser preparation of titanium nitride gradient coating on surface of titanium and titanium alloy | |
| CN101135050B (en) | Metasilicate cleaning inactivating process | |
| CN109338362B (en) | Method for preparing wear-resistant ceramic layer on surface of high-phosphorus cast iron | |
| Sepper et al. | The role of silicon in the hot dip galvanizing process. | |
| Umapathi et al. | Mechanical and tribological properties of electroless nickel phosphorous and nickel Phosphorous-Titanium nitride coating | |
| CN109750244A (en) | A method of mitigating malleable cast iron galvanizing by dipping pasc reaction | |
| CN103114267A (en) | Preparation method of steel substrate surface aluminum oxide coat | |
| CN104532316A (en) | Anti-nitridation process for copper-tin composite plating | |
| CN107460481A (en) | A kind of preparation method of Microarc Oxidation-Electroless Plating of Magnesium Alloy nickel composite coat | |
| CN104087889A (en) | Treatment method of successively aluminizing and oxidizing surface of die-casting die and oxidizing device | |
| WO2019065721A1 (en) | Method for producing plated black-heart malleable cast iron member, plated black-heart malleable cast iron member, and pipe fitting | |
| CN106756699A (en) | The method that a kind of step of structural steel two plates ZAM alloys | |
| RU2437967C1 (en) | Procedure for sedimentation of composite coating nickel-vanadium-phosphorus-boron nitride | |
| CN110616392B (en) | Surface pretreatment method for improving quality of malleable cast iron hot-dip galvanizing coating | |
| Gapsari et al. | The effect of hot dip galvanizing temperature to corrosion rate of steel as the material for chopper machine | |
| CN104195489B (en) | Hot-dipped Al-Ni alloy aluminized layer and hot-dipping method thereof | |
| CN113025845A (en) | Zinc-aluminum-magnesium alloy coating steel wire for bridge cable and preparation method thereof | |
| US4230507A (en) | Method for sulfurizing cast iron | |
| CN108754410B (en) | Preparation method of gradient coating for reinforcing surface of blanking die | |
| WO2019144491A1 (en) | Process for surface treatment of die-cast aluminum part | |
| CN109518109B (en) | FeAl/Al suitable for iron-based complex component2O3Preparation method of gradient tritium-resistant coating |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |