CN102995097A

CN102995097A - Electrolyte solution for surface etching of magnesium alloy and etching method of magnesium alloy surface

Info

Publication number: CN102995097A
Application number: CN2012104129722A
Authority: CN
Inventors: 黄远; 张丽芬; 何芳; 陆兆辉
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2012-10-25
Filing date: 2012-10-25
Publication date: 2013-03-27

Abstract

本发明公开了一种镁合金表面蚀刻方法，包括：对镁合金材料表面打磨、抛光、超声清洗，取适量的蚀刻电解质溶液，在25~35℃温度下，搅拌25~30min；在镁合金表面覆盖掩模；将上述处理过的镁合金材料浸渍于上述电解质溶液中，以镁合金材料作为阳极，Ag作为阴极，调节直流稳压稳流电源的电压为6~10V，温度控制在30℃，搅拌速度控制在30~60r/s，进行蚀刻20~40min；然后超声清洗；将蚀刻后的镁合金材料进行表面氟化处理后，揭去掩膜。本发明蚀刻方法能够很好的控制反应速度，抑制横向腐蚀，保证纵向腐蚀，提高镁合金的抗腐蚀性，而且该加工工艺简单，操作方便，具有广泛的应用前景。The invention discloses a magnesium alloy surface etching method, comprising: grinding, polishing, and ultrasonic cleaning the surface of a magnesium alloy material, taking an appropriate amount of etching electrolyte solution, and stirring for 25 to 30 minutes at a temperature of 25 to 35°C; Cover the mask; immerse the above-mentioned treated magnesium alloy material in the above-mentioned electrolyte solution, use the magnesium alloy material as the anode, and Ag as the cathode, adjust the voltage of the DC stabilized current power supply to 6~10V, and control the temperature at 30°C. The stirring speed is controlled at 30~60r/s, and the etching is carried out for 20~40min; then ultrasonically cleaned; after the surface fluorination treatment of the etched magnesium alloy material, the mask is removed. The etching method of the invention can well control the reaction speed, restrain the transverse corrosion, ensure the longitudinal corrosion, improve the corrosion resistance of the magnesium alloy, and the processing technology is simple, the operation is convenient, and the application prospect is wide.

Description

Mg alloy surface etching electrolyte solution and engraving method thereof

Technical field

The invention belongs to metal processing and process of surface treatment, particularly relate to a kind of magnesium alloy electrochemical etch process method.

Background technology

Magnesium alloy is one of metallic substance the lightest in using at present, has high specific tenacity, specific rigidity, good biocompatibility and mechanical property, and therefore in space flight, medical science, the fields such as electronics obtain increasing widespread use.But magnesium alloy chemical character is very active, and chemical corrosion very easily occurs, and therefore needs a kind of novel process that is applicable to magnesium alloy processing of exploitation.

At present little processing of metallic substance roughly is divided into dry etching and wet etching two large classes: dry etching comprises plasma etching, electron beam process, laser beam processing and gaseous state reactive ion etching etc.Wet etching is mainly chemical etching and electrochemical etching.The electrochemical etching method has that equipment is simple, and cost is low, the advantage of preparation condition gentleness, and by preparation new electrolyte solution and control stirring velocity, well suppress lateral etching, and guarantee vertical etching, be a kind of method with applications well prospect.Existing etching magnesium in the document, aluminium, the research of the metals such as titanium, the magnesium alloy apparatus obtains practical application at medical field.Magnesium alloy compares to other metals and has more physics, chemistry and biological property, thereby obtain broad research and use, but the research of relevant chemical etching magnesium alloy is less, so chemical etching MgCaZn alloy has important research and actual application value.

Magnesium alloy is carried out surface treatment, form anti-corrosion layer at Mg alloy surface, the partition magnesium alloy substrate contacts with corrosive atmosphere, is the effective means that improves Magnesium Anti-Corrosion.For reaching desirable anti-corrosion effects, anticorrosion layer must be evenly, and atresia has the strong characteristics of self-reparing capability and matrix adhesive force.The research of at present Mg alloy surface being processed is a lot, uses comparatively general method and mainly comprises the methods such as conversion film, organic coating, anodic oxidation, ion implantation, plating.

Summary of the invention

For above-mentioned prior art, the invention provides a kind of Mg alloy surface etching electrolyte solution and engraving method thereof, electrolyte solution among employing the present invention carries out etching and can be good at controlling speed of response, suppress lateral encroaching, guarantee vertically corrosion, by the aftertreatment of fluoridizing of effects on surface, can improve the erosion resistance of magnesium alloy, and complete processing is simple, and is easy to operate, is with a wide range of applications.

In order to solve the problems of the technologies described above, component and the volumetric molar concentration of Mg alloy surface etching electrolyte solution of the present invention are as follows:

NaNO ₂ 0.30~0.60mol/L；

NaOH 0.10~0.20mol/L；

Na ₂SiO ₃ 0.01~0.03mol/L；

NH ₄F 0.01~0.03mol/L；

EDTA 0.01~0.03mol/L。

The present invention utilizes above-mentioned electrolyte solution that the Mg alloy surface etching method be may further comprise the steps:

1) pre-treatment: to magnesium alloy materials surface finish, polishing, carry out ultrasonic cleaning with deionized water; Get any one electrolyte solution an amount of as in the claim 1 to 4, under 25 ~ 35 ℃ of temperature, stirring 25 ~ 30min;

2) mask: the double sticky tape paper that will have layout is bonded at the surface that magnesium alloy materials is wanted etched pattern, and remaining surface is sealed with adhesive tape;

3) etching: the magnesium alloy materials of above-mentioned processing be impregnated in the above-mentioned electrolyte solution, and as anode, Ag is as negative electrode with magnesium alloy materials, the voltage of regulating dc current regulator power supply is 6 ~ 10V, temperature is controlled at 30 ℃, and stirring velocity is controlled at 30 ~ 60r/s, carries out etching 20 ~ 40min; Then carry out ultrasonic cleaning with deionized water;

4) surface fluorination is processed: the NH that the magnesium alloy materials after the above-mentioned etching is dipped into 2.00 ~ 3.00mol/L of 60 ~ 80 ℃ ₄10 ~ 20min in the F solution takes out and carries out ultrasonic cleaning with deionized water, then places dehydrated alcohol to soak 12 ~ 18h, at last mask is removed, thereby, be formed with etched pattern on the magnesium alloy materials surface.

Compared with prior art, the invention has the beneficial effects as follows:

Utilize etching electrolyte solution provided by the invention that Mg alloy surface is carried out engraving method.Its technological process is simple, and is easy to operate, and the pattern of institute's etching meets design requirements.Wherein, it is to react by α-Mg that F-and etched surface occur to generate the magnesium fluoride reticulated structure that surface fluorination is processed, and then improves the erosion resistance of magnesium alloy.

Description of drawings

Fig. 1 adopts Mg alloy surface etched pattern that engraving method of the present invention obtains and the SEM photo of cross section, and wherein: a is the SEM photo of etched pattern, and b is the SEM photo of cross section;

Fig. 2 is that surface fluorination is processed forward and backward SEM photo in the magnesium alloy engraving method of the present invention, and wherein: a is the SEM photo of (Comparative Examples) before the fluoridation, and b is the SEM photo of (embodiment 1) after the fluoridation;

Fig. 3 is that surface fluorination is processed forward and backward polarization curve in the magnesium alloy engraving method of the present invention, and wherein: a is the polarization curve of (Comparative Examples) before the fluoridation, and b is the polarization curve of (embodiment 1) after the fluoridation.

Embodiment

Below in conjunction with preferred specific embodiment the present invention is described in further detail, but enforcement of the present invention is not limited to this.Wherein, magnesium alloy materials is chosen the Mg-Ca-Zn alloy, certainly, also can use the magnesium alloy materials such as Mg-Al-Zn alloy and Mg-Mn.

Comparative Examples 1:

According to the component in the following table 1 and volumetric molar concentration preparation magnesium alloy chemical etching electrolyte solution, under 30 ℃ of temperature, stir 30min, for subsequent use; Select a Mg-Ca-Zn alloy sheet sample to polish, polish, with deionized water carry out ultrasonic cleaning (if process after a while, should deposit in the ethanol stand-by, anti-oxidation); To be bonded at the double sticky tape paper of layout on request the one side of magnesium alloy thin slice, another side, the company's of reserving electrode area, rest part is sealed with adhesive tape; With above-mentioned magnesium alloy thin slice sample impregnated in the electrolyte solution for preparing (amount of this electrolyte solution according to container and in the size of etching magnesium alloy materials determine, do not have material to be advisable to soak) in, with the magnesium alloy thin slice of above-mentioned processing as anode, Ag is as negative electrode, the voltage of regulating dc current regulator power supply is 6 ~ 10V, temperature is controlled at 30 ℃, and stirring velocity is controlled at 30 ~ 60r/s, carries out etching 30min; Clean with the deionized water ultrasonic cleaning; Throw off double sticky tape paper, Mg-Ca-Zn alloy sheet surface forms sharply marginated etched pattern.

(a) among Fig. 2 is the SEM photo of the etched surfaces of Comparative Examples acquisition; (a) among Fig. 3 is the polarization curve of the etched surfaces of Comparative Examples acquisition.

Embodiment 1:

With the difference of Comparative Examples be: after the etching, carried out surface fluorination and process before throwing off double sticky tape paper: namely, the magnesium alloy thin slice sample that etching is good is dipped into 75 ℃, the NH of 2.00mol/L ₄15min in the F solution takes out and uses the deionized water ultrasonic cleaning clean, then places dehydrated alcohol to soak 12h, at last double sticky tape paper (mask) is removed, thereby, be formed with sharply marginated etched pattern at the Mg-Ca-Zn alloy material surface.

(a) among Fig. 1 is the SEM photo of the surface etching pattern of embodiment 1 acquisition, and (b) among Fig. 1 is the SEM photo of magnesium alloy cross section after the etching; (b) among Fig. 2 is the polarization curve of the etched surfaces of embodiment 1 acquisition.

Embodiment 2:

According to the component in the following table 1 and volumetric molar concentration preparation magnesium alloy chemical etching electrolyte solution, under 30 ℃ of temperature, stir 30min, for subsequent use; Following step with the difference of implementing 1 is: during surface fluorination was processed, the magnesium alloy thin slice sample that etching is good was dipped into 60 ℃, the NH of 3.00mol/L ₄20min in the F solution takes out and uses the deionized water ultrasonic cleaning clean, then places dehydrated alcohol to soak 14h, at last double sticky tape paper (mask) is removed, thereby, be formed with sharply marginated etched pattern at the Mg-Ca-Zn alloy material surface.

Embodiment 3:

According to the component in the following table 1 and volumetric molar concentration preparation magnesium alloy chemical etching electrolyte solution, under 30 ℃ of temperature, stir 30min, for subsequent use; Following step with the difference of implementing 1 is: during surface fluorination was processed, the magnesium alloy thin slice sample that etching is good was dipped into 80 ℃, the NH of 2.00mol/L ₄10min in the F solution takes out and uses the deionized water ultrasonic cleaning clean, then places dehydrated alcohol to soak 18h, at last double sticky tape paper (mask) is removed, thereby, be formed with sharply marginated etched pattern at the Mg-Ca-Zn alloy material surface.

Table 1

Although top invention has been described in conjunction with figure; but the present invention is not limited to above-mentioned embodiment; above-mentioned embodiment only is schematic; rather than restrictive; those of ordinary skill in the art is under enlightenment of the present invention; in the situation that does not break away from aim of the present invention, can also make a lot of distortion, these all belong within the protection of the present invention.

Claims

1. a magnesium alloy surface etching electrolytic solution, its component and molar concentration are:

NaNO ₂ 0.30~0.60mol/L;

NaOH 0.10~0.20mol/L;

Na ₂ SiO ₃ 0.01~0.03mol/L;

_NH4F 0.01~0.03mol/L;

EDTA 0.01~0.03mol/L.

2. The magnesium alloy surface etching electrolyte solution according to claim 1, wherein: NaNO ₂ is 0.60mol/L, NaOH is 0.10mol/L, Na ₂ SiO ₃ is 0.01mol/L, NH ₄ F is 0.15mol/L , EDTA is 0.01mol/L.

3. The magnesium alloy surface etching electrolyte solution according to claim 1, wherein: NaNO ₂ is 0.30mol/L, NaOH is 0.20mol/L, Na ₂ SiO ₃ is 0.03mol/L, and NH ₄ F is 0.03mol/L , EDTA is 0.015mol/L.

4. The magnesium alloy surface etching electrolyte solution according to claim 1, wherein: NaNO ₂ is 0.45mol/L, NaOH is 0.15mol/L, Na ₂ SiO ₃ is 0.02mol/L, and NH ₄ F is 0.02mol/L , EDTA is 0.03mol/L.

5. A magnesium alloy surface etching method, is characterized in that, comprises the following steps:

1) Pretreatment: Grinding and polishing the surface of the magnesium alloy material, and ultrasonically cleaning it with deionized water; taking an appropriate amount of the electrolyte solution according to any one of claims 1 to 4, and stirring it for 25~35°C at a temperature of 25~35°C 30min;

2) Mask: stick the double-sided tape paper with the design pattern on the surface of the magnesium alloy material to be etched, and seal the rest of the surface with tape;

3) Etching: Immerse the above-mentioned treated magnesium alloy material in the above-mentioned electrolyte solution, use the magnesium alloy material as the anode, and Ag as the cathode, adjust the voltage of the DC stabilized current power supply to 6~10V, and control the temperature at 30°C. The stirring speed is controlled at 30~60r/s, and the etching is performed for 20~40min; then ultrasonic cleaning is performed with deionized water;

4) Surface fluorination treatment: Soak the above etched magnesium alloy material in 2.00~3.00mol/L NH ₄ F solution at 60~80°C for 10~20min, take it out and perform ultrasonic cleaning with deionized water, and then place it in Soak in absolute ethanol for 12-18 hours, and finally remove the mask, so that an etching pattern is formed on the surface of the magnesium alloy material.