Colorful hot-dip galvanizing alloy and preparation method and use method thereof

Abstract

The invention provides a colored hot-dip galvanized alloy, which comprises the following components in percentage by mass: 0.03-0.15% of Ti; 0.03 to 0.15% of Mn; 0.01% to 0.06% of Y; < = 0.002% Al; mg < = 0.002%; < = 0.1% Ni; 0 to 0.01 percent of impurity elements; and the balance of Zn. The invention further provides a preparation method and a use method of the colored hot-dip galvanized alloy. According to the colorful hot-dip galvanizing alloy and the preparation method and the using method thereof, the hot-dip galvanizing temperature is low, the surface color of a galvanizing layer can be controlled through temperature change, and the corrosion resistance of the galvanizing layer is very excellent.

Description

Technical Field

[0001] The invention relates to the technical field of material surface treatment, and in particular to a colored hot-dip galvanized alloy and a preparation method and a use method thereof. Background Art

[0002] Hot-dip galvanizing is the most economical and effective way to protect steel from corrosion. It is widely used in various fields such as transportation, chemical industry, machinery, water conservancy, electricity, and infrastructure. The steel coated by the traditional hot-dip galvanizing process is a single silver-white color with a bright metallic luster. In some areas, the highly reflective silver-white galvanized steel has a great contrast with the landform environment, destroying the harmony of the natural environment and causing serious light pollution. Therefore, the single silver-white color is difficult to meet the color requirements of steel in some special environments.

[0003] Therefore, there is an urgent need for a method for preparing a colored hot-dip galvanized layer with simple process, short production cycle, low cost, and good corrosion resistance, weather resistance and decorative properties of the obtained coating. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a colored hot-dip galvanized alloy with low hot-dip temperature, controllable surface color of the galvanized layer by temperature change and excellent corrosion resistance of the galvanized layer, as well as a preparation method and a use method thereof.

[0005] To solve the above technical problems, the present invention provides a colored hot-dip galvanized alloy, which includes, by mass percentage, 0.03-0.15% Ti; 0.03-0.15% Mn; 0.01-0.06% Y; Al≤0.002%; Mg≤0.002%; Ni≤0.1%; 0-0.01% impurity elements; and the rest is Zn.

[0006] The present invention also provides a method for preparing a colored hot-dip galvanized alloy, comprising the following steps:

[0007] Melt pure zinc at 430-600℃ and keep it warm for 5-20min to obtain zinc liquid;

[0008] Adding Zn-Ti master alloy, Zn-Mn master alloy and Zn-Y master alloy to the zinc liquid in sequence, stirring and standing for 3 to 15 minutes after melting to obtain zinc alloy liquid;

[0009] The zinc alloy liquid is cast to obtain a colored hot-dip galvanized alloy.

[0010] Furthermore, the Zn-Ti master alloy, the Zn-Mn master alloy and the Zn-Y master alloy are all master alloys obtained by vacuum melting.

[0011] Furthermore, the Ti content in the Zn-Ti master alloy is 0.1-3.0wt%, the Mn content in the Zn-Mn master alloy is 0.1-3.0wt%, and the Y content in the Zn-Y master alloy is 0.03-2.0wt%.

[0012] Furthermore, the pure zinc is pure zinc with a zinc content of not less than 99.995%.

[0013] Furthermore, the zinc liquid is added to the three master alloys and then smelted at 430-600° C. to obtain a zinc alloy liquid.

[0014] Furthermore, the zinc alloy liquid comprises, by mass percentage, 0.03-0.15% Ti, 0.03-0.15% Mn, 0.01-0.06% Y, ≤0.002% Al, ≤0.002% Mg, ≤0.002% Ni, 0-0.01% impurity elements, and the rest is Zn.

[0015] The present invention also provides a method for using the colored hot-dip galvanized alloy, comprising the following steps:

[0016] The colored hot-dip galvanized alloy is placed in a molten pool and heated at 430-530°C to form a colored hot-dip galvanized alloy plating solution;

[0017] The steel parts are placed in a colored hot-dip galvanizing alloy plating solution for immersion plating;

[0018] By adjusting the dipping temperature within 430-530℃, a colored hot-dip galvanized layer of the desired color can be formed on the surface of the steel part.

[0019] Furthermore, dipping at 430°C can form a silvery white hot-dip galvanized layer on the surface of the steel part, dipping at 450°C can form a light yellow hot-dip galvanized layer on the surface of the steel part, dipping at 460°C can form a yellow hot-dip galvanized layer on the surface of the steel part, dipping at 470°C can form a blue hot-dip galvanized layer on the surface of the steel part, dipping at 480°C can form a dark blue hot-dip galvanized layer on the surface of the steel part, and dipping at 530°C can form a cyan hot-dip galvanized layer on the surface of the steel part.

[0020] Furthermore, the steel part is placed in the colored hot-dip galvanizing alloy plating solution for a plating time of 0.5 to 10 minutes.

[0021] The present invention provides a colored hot-dip galvanized alloy, in which 0.03-0.15% Ti, 0.03-0.15% Mn, and 0.01-0.06% Y are added by mass percentage. Since the oxidation ability of Ti, Mn, and Y elements is stronger than that of zinc, they will react with oxygen in the air to generate a variety of oxides with certain colors. At different temperatures, when the steel parts are taken out from the hot-dip galvanized alloy plating solution, the surface temperature of the hot-dip galvanized layer will be different. The higher the temperature of the hot-dip galvanized alloy plating solution, the higher the temperature of the hot-dip galvanized layer on the surface of the steel parts taken out, the more intense the oxidation reaction between the hot-dip galvanized layer and oxygen, and the longer the oxidation time, thereby increasing the thickness of the oxide layer of the hot-dip galvanized layer. Due to the change in the thickness of the oxide layer of the hot-dip galvanized layer, the optical path difference will change, which is manifested as a change in the color of the hot-dip galvanized layer. Therefore, the colored hot-dip galvanized alloy provided by the present invention can form a colored hot-dip galvanized layer of various colors on the surface of the steel part by adjusting the immersion temperature within the temperature range of 430 to 530°C when hot-dip galvanizing the steel part, thereby making the hot-dip galvanized layer show different colors.

[0022] Therefore, the colored hot-dip galvanized alloy provided by the present invention can not only increase the decorativeness of the hot-dip galvanized layer on the surface of the base material such as steel parts, but also improve the corrosion resistance of the material due to the addition of high-valent alloy element ions generated by the elements Ti, Mn and Y.

[0023] Furthermore, the colored hot-dip galvanized alloy provided by the present invention can not only control the color of the surface of the galvanized layer by changing the temperature when the base material such as steel parts is dip-plated to form a colored hot-dip galvanized layer, but also the hot-dip plating temperature when the base material such as steel parts is dip-plated to form a colored hot-dip galvanized layer is relatively low, which can save energy and reduce consumption and production costs. At the same time, the Zn-Fe-Ti-based ternary compound in the obtained colored hot-dip galvanized layer is relatively small, which can not only effectively reduce the consumption of the alloy element Ti in the plating solution, but also increase the surface quality of the galvanized layer, and at the same time effectively improve the corrosion resistance of the galvanized layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A flow chart of a method for preparing a colored hot-dip galvanized alloy provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The embodiment of the present invention provides a colored hot-dip galvanized alloy, which includes, by mass percentage, 0.03-0.15% Ti, 0.03-0.15% Mn, 0.01-0.06% Y, ≤0.002% Al, ≤0.002% Mg, ≤0.1% Ni, 0-0.01% impurity elements, and the rest is Zn.

[0026] See also Figure 1 The present invention provides a method for preparing a colored hot-dip galvanized alloy, comprising the following steps:

[0027] Step 1) pure zinc is melted at 430-600° C. and kept warm for 5-20 minutes to obtain zinc liquid.

[0028] Wherein, the pure zinc is pure zinc with a zinc content of not less than 99.995%.

[0029] As a specific embodiment of the present invention, when melting pure zinc, the graphite crucible is first preheated to 430-600°C, and then the pure zinc is added to the preheated graphite crucible, and the heating is continued to control the temperature of the graphite crucible at 430-600°C until the pure zinc in the graphite crucible is melted into zinc liquid.

[0030] Step 2) Add Zn-Ti master alloy, Zn-Mn master alloy and Zn-Y master alloy to the zinc liquid in sequence, stir and stand for 3 to 15 minutes after smelting to obtain zinc alloy liquid.

[0031] Among them, since Zn, Ti, Mn, and Y are relatively active metals, in order to prevent Zn, Ti, Mn, and Y from being oxidized by oxygen in the air during the smelting process, the Zn-Ti master alloy, the Zn-Mn master alloy, and the Zn-Y master alloy are all master alloys obtained by vacuum melting.

[0032] The Ti content in the Zn-Ti master alloy is 0.1-3.0wt%, the Mn content in the Zn-Mn master alloy is 0.1-3.0wt%, and the Y content in the Zn-Y master alloy is 0.03-2.0wt%.

[0033] Among them, after adding three kinds of intermediate alloys into the zinc liquid, it is smelted at 430-600°C, stirred evenly after being completely melted, and allowed to stand for 3-15 minutes, and the zinc slag on the surface is removed to obtain the zinc alloy liquid.

[0034] The obtained zinc alloy liquid includes, by mass percentage, 0.03-0.15% Ti, 0.03-0.15% Mn, 0.01-0.06% Y, ≤0.002% Al, ≤0.002% Mg, ≤0.002% Ni, 0-0.01% impurity elements, and the rest is Zn.

[0035] Step 3) Casting the zinc alloy liquid to obtain a colored hot-dip galvanized alloy.

[0036] The present invention provides a method for using a colored hot-dip galvanized alloy, comprising the following steps:

[0037] First, the colored hot-dip galvanized alloy is placed in a molten pool and heated at a temperature of 430-530° C. to form a colored hot-dip galvanized alloy plating solution.

[0038] Then, the steel parts are placed in a colored hot-dip galvanizing alloy plating solution for immersion plating.

[0039] Finally, within the temperature range of 430-530°C, a colored hot-dip galvanized layer of the desired color can be formed on the surface of the steel part by adjusting the dipping temperature.

[0040] Since the Ti, Mn, and Y elements in the colored hot-dip galvanized alloy have stronger oxidizing power than zinc, they will react with oxygen in the air to generate various oxides. When the immersion temperature is controlled at different temperatures within the temperature range of 430-530°C, there will be differences in the surface temperature of the hot-dip galvanized layer after the steel parts are taken out from the hot-dip galvanized alloy bath. The higher the temperature of the hot-dip galvanized alloy bath, the higher the temperature of the hot-dip galvanized layer on the surface of the steel parts taken out, the more intense the oxidation reaction between the hot-dip galvanized layer and oxygen, and the longer the oxidation time, which increases the thickness of the oxide layer of the hot-dip galvanized layer. Due to the change in the thickness of the oxide layer of the hot-dip galvanized layer, the optical path difference will change, which is manifested as a change in the color of the hot-dip galvanized layer, so that the hot-dip galvanized layer shows different colors.

[0041] Specifically, when the dipping temperature is controlled at 430°C, a silvery-white hot-dip galvanized layer can be formed on the surface of the steel part after dipping; when the dipping temperature is controlled at 450°C, a light yellow hot-dip galvanized layer can be formed on the surface of the steel part after dipping; when the dipping temperature is controlled at 460°C, a yellow hot-dip galvanized layer can be formed on the surface of the steel part after dipping; when the dipping temperature is controlled at 470°C, a blue hot-dip galvanized layer can be formed on the surface of the steel part after dipping; when the dipping temperature is controlled at 480°C, a dark blue hot-dip galvanized layer can be formed on the surface of the steel part after dipping; when the dipping temperature is controlled at 530°C, a cyan hot-dip galvanized layer can be formed on the surface of the steel part after dipping.

[0042] In order to make the hot-dip galvanized layer beautiful and to make the hot-dip galvanized layer harmonious with the surrounding environment, as a specific embodiment of the present invention, the dipping temperature is usually controlled to 450°C to form a light yellow hot-dip galvanized layer on the surface of the steel part; or the dipping temperature is controlled to 460°C to form a yellow hot-dip galvanized layer on the surface of the steel part; or the dipping temperature is controlled to 470°C to form a blue hot-dip galvanized layer on the surface of the steel part; or the dipping temperature is controlled to 480°C to form a dark blue hot-dip galvanized layer on the surface of the steel part.

[0043] The steel parts are placed in a colored hot-dip galvanizing alloy plating solution, the immersion temperature is controlled within a temperature range of 430 to 530°C, and the immersion time is 0.5 to 10 minutes, so that hot-dip galvanizing layers of different colors can be obtained on the surface of the steel parts.

[0044] In addition, the colored hot-dip galvanized alloy provided by the present invention has 0.03-0.15% Ti, 0.03-0.15% Mn, and 0.01-0.06% Y added to the zinc alloy, so that the hot-dip galvanized layer formed by immersion plating on the surface of the steel part can improve the corrosion resistance of the hot-dip galvanized layer because the addition of Ti, Mn, and Y elements forms high-valent alloy element ions.

[0045] At the same time, the colored hot-dip galvanized alloy provided by the present invention can form a colored hot-dip galvanized layer in various colors on the surface of the steel part by adjusting the immersion temperature within the temperature range of 430 to 530°C when immersing a base material such as a steel part to form a colored hot-dip galvanized layer. The hot-dip galvanizing temperature is relatively low, which can save energy and reduce consumption and reduce production costs.

[0046] Moreover, the obtained colored hot-dip galvanized layer contains relatively less Zn-Fe-Ti based ternary compounds, which can not only effectively reduce the consumption of alloy element Ti in the plating solution, but also increase the surface quality of the galvanized layer, and at the same time effectively improve the corrosion resistance of the galvanized layer.

[0047] The following is a detailed description of a colored hot-dip galvanized alloy provided by the present invention and its preparation method and use method through comparative examples and embodiments.

[0048] Comparative Example 1

[0049] A pure zinc ingot with a Zn content of 99.995% is placed in a graphite crucible and heated to melt to form a pure zinc plating solution. The steel plated parts that have undergone surface pretreatment such as NaOH solution alkaline washing → water washing → hydrochloric acid pickling → water washing → zinc oxide ammonium solution plating → drying are placed vertically in the pure zinc plating solution. The immersion temperature is controlled at 450°C and the immersion time is 2 minutes. Before taking out the steel plated parts, use a scraper to remove the oxide slag on the surface of the plating solution, and then slowly take out the steel plated parts from the plating solution. After air cooling, a silver-white hot-dip galvanizing layer can be formed on the surface of the steel plated parts.

[0050] Example 1

[0051] This embodiment provides a preferred solution for a method for preparing a colored hot-dip galvanized alloy and a method for using the same, as follows.

[0052] Preheat the graphite crucible at 550°C, then add a pure zinc ingot with a Zn content of 99.995% (with an Al content of less than 0.002%) and melt it, then add Zn-1.4wt%Ti master alloy, Zn-1.2wt.%Mn master alloy, and Zn-0.8wt.%Y master alloy in turn, and after the master alloy is completely melted, stir for 0.5min and then stand for 5min, remove the zinc slag on the surface of the zinc alloy liquid, and finally cast the zinc alloy liquid to obtain the desired colored hot-dip zinc alloy ingot. The weight ratio of the pure zinc ingot and the vacuum-melted Zn-1.4wt%Ti master alloy, Zn-1.2wt.%Mn master alloy, and Zn-0.8wt.%Y master alloy is 84.6:5.4:5.4:5.

[0053] The prepared zinc alloy ingot for color hot dip plating is placed in a molten pool for melting to obtain a zinc alloy plating solution for color hot dip plating, and then the temperature of the zinc alloy plating solution for color hot dip plating is controlled to 450°C for subsequent hot dip galvanizing operations. The steel plated parts that have undergone surface pretreatments such as NaOH solution alkaline washing → water washing → hydrochloric acid pickling → water washing → zinc ammonium oxide solution plating → drying are placed vertically in the zinc alloy plating solution for color hot dip plating, and the immersion time is 2 minutes. Before taking out the steel plated parts, use a scraper to remove the oxide slag on the surface of the plating solution, and then slowly take out the steel plated parts from the plating solution. After air cooling, a layer of light yellow hot dip galvanized layer can be formed on the surface of the steel plated parts.

[0054] The corrosion resistance of the coating obtained in Example 1 was tested by polarization curve using a PAMSTAT 4000A electrochemical workstation, and compared with the corrosion resistance of the silver-white coating obtained by the conventional hot-dip galvanizing method in Comparative Example 1. The polarization curve test parameter values ​​of Example 1 and Comparative Example 1 are shown in Table 1.

[0055] Table 1

[0056] Electrochemical parameters <![CDATA[Polarization resistance (Ω / cm 2 )]]> <![CDATA[Corrosion current density (A / cm 2 )]]> Example 1 2353 <![CDATA[1.096×10 -5 ]]> Comparative Example 1 1731 <![CDATA[1.9548×10 -5 ]]>

[0057] It can be seen from Table 1 that the polarization resistance of the light yellow hot-dip galvanized layer in Example 1 of the present invention is greater than that of the silvery white hot-dip galvanized layer in Comparative Example 1, while the corrosion current density is less than that of the silvery white galvanized layer in Comparative Example 1. This shows that the corrosion resistance of the light yellow coating in Example 1 of the present invention is better than that of the silvery white galvanized layer.

[0058] The light yellow coating obtained in Example 1 has a uniform thickness. According to the coating thickness determination method of GB / T 13448-2006, the coating thickness is measured at three different positions of the coating, namely, the upper, middle and lower positions. The thickness values ​​are shown in Table 2.

[0059] Table 2

[0060] serial number Thickness / μm 1 46 2 48 3 51 Very bad 5 average value 48.3

[0061] The hot-dip galvanized layer obtained in Example 1 has a small oxide layer thickness and a light color, and is a light yellow galvanized layer, due to the low hot-dip plating temperature and weak oxidation reaction. As can be seen from Table 2, the coating thickness is uniform, the range is 5 μm, and the average thickness is 48.3 μm, and the coating thickness meets the process standard requirements.

[0062] The silver-white coating obtained in Comparative Example 1 has a uniform thickness. According to the coating thickness determination method of GB / T 13448-2006, the coating thickness is measured at three different positions of the coating, namely, the upper, middle and lower positions. The thickness values ​​are shown in Table 3.

[0063] Table 3

[0064] serial number Thickness / μm 1 112 2 119 3 128 Very bad 16 average value 119.67

[0065] Comparative Example 1 is a silvery-white zinc-plated layer. Since the zinc-plated layer is not interfered by other oxidizing elements except zinc, the oxidation reaction is extremely weak, and the coating grows faster, thereby obtaining a thicker zinc-plated layer. As can be seen from Table 3, the thickness of the traditional silvery-white coating of Comparative Example 1 is uniform, with a range of 16 μm and an average thickness of 119.67 μm. The silvery-white zinc-plated layer of Comparative Example 1 is higher than the colored zinc-plated layer in the embodiment, indicating that the colored zinc alloy plating solution can reduce the coating thickness.

[0066] Example 2

[0067] The difference between this embodiment and embodiment 1 is that the immersion plating temperature is adjusted to 460° C., and the rest of the preparation process and the use process are the same as those in embodiment 1. Finally, a yellow hot-dip galvanizing layer can be formed on the surface of the steel plated part.

[0068] The corrosion resistance of the coating obtained in Example 2 was tested by polarization curve using a PAMSTAT 4000A electrochemical workstation, and compared with the corrosion resistance of the silver-white coating obtained by the conventional hot-dip galvanizing method in Comparative Example 1. The polarization curve test parameter values ​​of Example 2 and Comparative Example 1 are shown in Table 4.

[0069] Table 4

[0070] Electrochemical parameters <![CDATA[Polarization resistance (Ω / cm 2 )]]> <![CDATA[Corrosion current density (A / cm 2 )]]> Example 2 2482 <![CDATA[6.8474×10 -6 ]]> Comparative Example 1 1731 <![CDATA[1.9548×10 -5 ]]>

[0071] It can be seen from Table 4 that the polarization resistance of the yellow coating in Example 2 is greater than that of the silver-white zinc coating in Comparative Example 1, and the corrosion current density is less than that of the silver-white zinc coating in Comparative Example 1. The corrosion resistance of the yellow coating in Example 2 is better than that of the silver-white zinc coating in Comparative Example 1.

[0072] The yellow coating obtained in Example 2 has a uniform thickness. According to the coating thickness determination method of GB / T 13448-2006, the coating thickness is measured at three different positions of the coating, namely, the top, middle and bottom. The thickness values ​​are shown in Table 5.

[0073] Table 5

[0074] serial number Thickness / μm 1 64 2 71 3 67 Very bad 7 average value 67.3

[0075] The hot-dip galvanized layer obtained in Example 2 has an increased oxidation reaction due to the increase in hot-dip plating temperature, and the thickness of the oxide layer of the hot-dip galvanized layer increases, and the color becomes darker, turning into a yellow galvanized layer. As can be seen from Table 5, the coating thickness is uniform, the range is 7 μm, and the average thickness is 67.3 μm. The coating thickness meets the process standard requirements.

[0076] Example 3

[0077] The difference between this embodiment and embodiment 1 is that the immersion plating temperature is adjusted to 470° C., and the rest of the preparation process and the use process are the same as those in embodiment 1. Finally, a blue hot-dip galvanizing layer can be formed on the surface of the steel plated part.

[0078] The corrosion resistance of the coating obtained in Example 3 was tested by polarization curve using a PAMSTAT 4000A electrochemical workstation, and compared with the corrosion resistance of the silver-white coating obtained by the conventional hot-dip galvanizing method in Comparative Example 1. The polarization curve test parameter values ​​of Example 3 and Comparative Example 1 are shown in Table 6.

[0079] Table 6

[0080] Electrochemical parameters <![CDATA[Polarization resistance (Ω / cm 2 )]]> <![CDATA[Corrosion current density (A / cm 2 )]]> Example 3 2778 <![CDATA[7.226×10 -6 ]]> Comparative Example 1 1731 <![CDATA[1.9548×10 -5 ]]>

[0081] It can be seen from Table 6 that the polarization resistance of the blue coating in Example 3 is greater than that of the silver-white zinc coating in Comparative Example 1, and the corrosion current density is less than that of the silver-white zinc coating in Comparative Example 1. The corrosion resistance of the blue coating in Example 3 is better than that of the silver-white zinc coating in Comparative Example 1.

[0082] The blue coating obtained in Example 3 has a uniform thickness. According to the coating thickness determination method of GB / T 13448-2006, the coating thickness is measured at three different positions of the coating, namely, the top, middle and bottom. The thickness values ​​are shown in Table 7.

[0083] Table 7

[0084] serial number Thickness / μm 1 87 2 75 3 71 Very bad 16 average value 77.6

[0085] The hot-dip galvanized layer obtained in Example 3 has a stronger oxidation reaction due to the continued increase in hot-dip coating temperature, and the thickness of the oxide layer of the hot-dip galvanized layer increases, and the color becomes darker, turning into a blue galvanized layer. As can be seen from Table 7, the coating thickness is uniform, the range is 16 μm, and the average thickness is 77.6 μm. The coating thickness meets the process standard requirements.

[0086] Example 4

[0087] The difference between this embodiment and embodiment 1 is that the immersion plating temperature is adjusted to 480° C., and the rest of the preparation process and the use process are the same as those in embodiment 1. Finally, a dark blue hot-dip galvanizing layer can be formed on the surface of the steel plated part.

[0088] The corrosion resistance of the coating obtained in Example 4 was tested by polarization curve using a PAMSTAT 4000A electrochemical workstation, and compared with the corrosion resistance of the silver-white coating obtained by the conventional hot-dip galvanizing method in Comparative Example 1. The polarization curve test parameter values ​​of Example 4 and Comparative Example 1 are shown in Table 8.

[0089] Table 8

[0090] Electrochemical parameters <![CDATA[Polarization resistance (Ω / cm 2 )]]> <![CDATA[Corrosion current density (A / cm 2 )]]> Example 4 2328 <![CDATA[1.1107×10 -5 ]]> Comparative Example 1 1731 <![CDATA[1.9548×10 -5 ]]>

[0091] It can be seen from Table 8 that the polarization resistance of the dark blue coating in Example 4 is greater than that of the silver-white galvanized coating in Comparative Example 1, and the corrosion current density is less than that of the silver-white galvanized coating in Comparative Example 1. The corrosion resistance of the dark blue coating in Example 4 is better than that of the silver-white galvanized coating in Comparative Example 1.

[0092] The dark blue coating obtained in Example 4 has a uniform thickness. According to the coating thickness determination method of GB / T 13448-2006, the coating thickness is measured at three different positions of the coating, namely, the top, middle and bottom. The thickness values ​​are shown in Table 9.

[0093] Table 9

[0094] serial number Thickness / μm 1 58 2 65 3 56 Very bad 9 average value 59.66

[0095] The hot-dip galvanized layer obtained in Example 4, as the hot-dip temperature continues to rise, the oxidation reaction is stronger, and the increase in temperature becomes an important influence on the thickness of the coating, resulting in a decrease in the thickness of the galvanized layer and a darker color, turning into a dark blue galvanized layer. It can be seen that the coating thickness is uniform, the range is 9 μm, and the average thickness is 59.66 μm, and the coating thickness meets the process standard requirements.

[0096] The invention provides a colored hot-dip galvanized alloy, wherein the controlled components and their mass percentages are Ti 0.03-0.15%; Mn 0.03-0.15%; Y 0.01-0.06%; Al≤0.002%; Mg≤0.002%; Ni≤0.1%; impurity elements 0-0.01%; and the rest is Zn. The hot-dip galvanized layer formed by immersion plating the hot-dip galvanized alloy on the surface of a steel sample not only has better corrosion resistance than a traditional galvanized layer, but also has a thickness that meets the requirements of process standards. At the same time, by controlling the plating solution temperature within the range of 430-530°C during hot-dip plating, a hot-dip galvanized layer in colors such as light yellow, golden yellow, light blue, dark blue and purple can be obtained, so that the galvanized steel can meet the requirements for the color of steel in a variety of special environments.

[0097] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A colored hot-dip galvanized alloy, characterized in that: Calculated by mass percentage, it includes Ti 0.03-0.15%; Mn 0.03-0.15%; Y 0.01-0.06%; Al≤0.002%; Mg≤0.002%; Ni≤0.1%; impurity elements 0-0.01%; and the rest is Zn.

2. A method for preparing a colored hot-dip galvanized alloy, characterized in that: The steps include: Melt pure zinc at 430-600℃ and keep it warm for 5-20min to obtain zinc liquid; Adding Zn-Ti master alloy, Zn-Mn master alloy and Zn-Y master alloy to the zinc liquid in sequence, stirring and standing for 3 to 15 minutes after smelting to obtain zinc alloy liquid; The zinc alloy liquid is cast to obtain a colored hot-dip galvanized alloy.

3. The method for preparing a colored hot-dip galvanized alloy according to claim 2, characterized in that: The Zn-Ti master alloy, the Zn-Mn master alloy and the Zn-Y master alloy are all master alloys obtained by vacuum melting.

4. The method for preparing a colored hot-dip galvanized alloy according to claim 3, characterized in that: The content of Ti in the Zn-Ti master alloy is 0.1-3.0 wt %, the content of Mn in the Zn-Mn master alloy is 0.1-3.0 wt %, and the content of Y in the Zn-Y master alloy is 0.03-2.0 wt %.

5. The method for preparing a colored hot-dip galvanized alloy according to claim 4, characterized in that: The pure zinc is pure zinc with a zinc content of not less than 99.995%.

6. The method for preparing a colored hot-dip galvanized alloy according to claim 5, characterized in that: The zinc liquid is added with the three master alloys and then smelted at 430-600° C. to obtain a zinc alloy liquid.

7. The method for preparing a colored hot-dip galvanized alloy according to claim 6, characterized in that: The zinc alloy liquid comprises, by mass percentage, 0.03-0.15% Ti, 0.03-0.15% Mn, 0.01-0.06% Y, Al≤0.002%, Mg≤0.002%, Ni≤0.1%, 0-0.01% impurity elements, and the rest is Zn.

8. A method for using a colored hot-dip galvanized alloy, characterized in that: The steps include: The colored hot-dip galvanized alloy is placed in a molten pool and heated at 430-530°C to form a colored hot-dip galvanized alloy plating solution; The steel parts are placed in a colored hot-dip galvanizing alloy plating solution for immersion plating; By adjusting the dipping temperature within 430-530℃, a colored hot-dip galvanized layer of the desired color can be formed on the surface of the steel part.

9. The method for using the colored hot-dip galvanized alloy according to claim 8, characterized in that: Dipping at 430℃ can form a silvery-white hot-dip galvanized layer on the surface of steel parts, dipping at 450℃ can form a light yellow hot-dip galvanized layer on the surface of steel parts, dipping at 460℃ can form a yellow hot-dip galvanized layer on the surface of steel parts, dipping at 470℃ can form a blue hot-dip galvanized layer on the surface of steel parts, dipping at 480℃ can form a dark blue hot-dip galvanized layer on the surface of steel parts, and dipping at 530℃ can form a cyan hot-dip galvanized layer on the surface of steel parts.

10. The method for using the colored hot-dip galvanized alloy according to claim 9, characterized in that: The steel part is placed in the color hot-dip zinc alloy plating solution for 0.5 to 10 minutes.

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