CN102181910B

CN102181910B - Thin-layer thickness uniform treatment method for surface of MB8 magnesium alloy

Info

Publication number: CN102181910B
Application number: CN2011101016662A
Authority: CN
Inventors: 杜云慧; 张鹏; 刘汉武; 卢小鹏
Original assignee: Beijing Jiaotong University
Current assignee: Beijing Jiaotong University
Priority date: 2011-04-22
Filing date: 2011-04-22
Publication date: 2012-07-11
Anticipated expiration: 2031-04-22
Also published as: CN102181910A

Abstract

The invention discloses a thin-layer thickness uniform treatment method for the surface of MB8 magnesium alloy and belongs to the field of research on thin-layer thickness uniform treatment of the surface of the MB8 magnesium alloy. In the method, on the basis of an alternating-current (AC) plasma micro-arc oxidation treatment method, oxygen gas is sprayed into treating liquid so as to improve the reaction uniformity of the treating liquid and the magnesium alloy, and under the conditions that the concentration of potassium fluoride is 1,311 to 1,313g/L, the concentration of potassium hydroxide is 359 to 361g/L, the concentration of sodium silicate is 105 to 107g/L, the power frequency AC voltage is 47 to 49V and the spraying amount of the oxygen gas for each liter of treating liquid is 0.006 to 0.009L/s, the MB8 magnesium alloy undergoes AC plasma micro-arc oxidation surface treatment for 62 to 82 seconds, so that a protective thin layer which is uniform in thickness and of which the thickness is 8 to 14 mu m is formed on the surface of the MB8 magnesium alloy.

Description

A kind of MB8 Mg alloy surface thickness of thin layer even processing method

Technical field

The present invention relates to a kind of MB8 Mg alloy surface thickness of thin layer even processing method.

Background technology

Publication number: CN1900382A; Denomination of invention: on " a kind of MB8 surface treatment method of Mg alloy "; Set forth MB8 magnesiumalloy ac plasma differential arc oxidation treatment method; That is, adopt the treatment solution that contains Potassium monofluoride and Pottasium Hydroxide, the power frequency AC of being controlled by voltate regulator provides electric energy; At each power frequency ac voltage in the cycle, the TRANSIENT HIGH TEMPERATURE of utilizing yin, yang ion in the treatment solution to carry out the plasma micro-arc discharge generation at the MB8 Mg alloy surface forms resist at the MB8 Mg alloy surface.Utilize this ac plasma differential arc oxidation treatment method; Disclosed Potassium monofluoride concentration is that 1051～1200g/L, concentration of potassium hydroxide are that 371～400g/L, power frequency ac voltage are under 50～61V condition in patent CN1900382A; Can be in 90～120 seconds, make that MB8 Mg alloy surface growth in situ goes out that 15～35 μ m are thick, homogeneous microstructure and complete resist.But, adopt the CN1900382A patented process at the thin layer of mean thickness below 15 μ m that the MB8 Mg alloy surface forms, exist comparatively serious became uneven to spare phenomenon, its corrosion resistance nature is relatively poor.

For the sealer of MB8 magnesiumalloy, less especially when 15 μ m are following at mean thickness, its thickness is even more, and corrosion resistance nature is good more, and therefore, during less than 15 μ m, MB8 Mg alloy surface thickness of thin layer is more evenly good more at mean thickness.

Summary of the invention

Technical problem to be solved by this invention is; Overcome the deficiency of existing ac plasma differential arc oxidation treatment method " the skin layer thickness evenness is poor "; A kind of ac plasma differential arc oxidation treatment method that can form the uniform thin layer of thickness at the MB8 Mg alloy surface is provided, further improves the thickness evenness of MB8 Mg alloy surface thin layer.

The technical solution adopted for the present invention to solve the technical problems is: on ac plasma differential arc oxidation treatment method basis; In treatment solution, spray into oxygen to improve treatment solution and magnesiumalloy reaction uniformity; And be that 1311～1313g/L, concentration of potassium hydroxide are that 359～361g/L, sodium silicate silicate are that 105～107g/L, power frequency ac voltage are that 47～49V, every liter of treatment solution oxygen straying quatity are under 0.006～0.009L/s condition in Potassium monofluoride concentration, the MB8 magnesiumalloy is carried out 62～82 seconds ac plasma Microarc Oxidation Surface Treatment.

The invention has the beneficial effects as follows: for the sealer of magnesiumalloy, want to improve the homogeneity of its thickness, must strengthen treatment solution and magnesiumalloy are reacted inhomogeneity control.When magnesiumalloy is carried out surface treatment, because the chemical ingredients of Mg alloy surface is different, therefore; Under the effect of impressed electromotive force, the ion in the treatment solution will converge to the little Mg alloy surface place of energy consumption, cause the inhomogeneous of surface reaction; Thereby the became uneven that causes sealer; If when carrying out surface treatment, through in treatment solution, spraying into oxygen treatment solution is stirred, then the ion in the treatment solution will be dispersed in the treatment solution relatively equably; Thereby can avoid a large amount of ions in the treatment solution to converge phenomenon, and then the homogeneity of Mg alloy surface protective layer thickness is improved to the little Mg alloy surface place of energy consumption; In addition; The high temperature that surface reaction produces can cause the oxygen that sprays in the treatment solution to form a large amount of oxygen plasmas; These oxygen plasmas have poising action to the reaction of Mg alloy surface; Will further improve the homogeneity of surface reaction; The present invention utilizes the stirring action of the oxygen of each surface treatment parameter optimization combination back formation and oxygen plasma to the poising action of Mg alloy surface reaction, has further improved treatment solution and magnesiumalloy reaction uniformity, thereby has reached the inhomogeneity purpose of raising Mg alloy surface protective layer thickness.Utilize the present invention, the MB8 magnesiumalloy is carried out surface treatment, can in 62～82 seconds, obtain the thick protection thin layer of uniform 8～14 μ m of thickness.

Description of drawings

Fig. 1 carries out the front view of surface processing device to the MB8 magnesiumalloy for the inventive method.

Among the figure, power frequency AC 1, lead 2, voltate regulator 3, lead 4, MB8 magnesium alloy workpiece 5, treatment solution 6, oxygen jet 7, oxygen pump 8, treatment trough 9.

Fig. 2 is the microtexture at the processing interface of adopting the inventive method that the MB8 magnesiumalloy is carried out to obtain after the surface treatment.

Embodiment

In conjunction with accompanying drawing the inventive method is carried out specifying as follows of surface processing device to the MB8 magnesiumalloy:

The MB8 magnesiumalloy is carried out surface processing device mainly to be comprised: power frequency AC 1, voltate regulator 3, oxygen jet 7, oxygen pump 8, treatment trough 9.

The input terminus of voltate regulator 3 links to each other through lead 2 with power frequency AC 1, and the output terminal of voltate regulator 2 links to each other through lead 4 with MB8 magnesium alloy workpiece 5.Oxygen jet 7 adopts the teflon seal mode of connection to be fixed on the bottom of treatment trough 9, and the one of which end stretches in the treatment solution 6, and the other end links to each other with oxygen pump 8.

Power frequency AC 1 is an industry power frequency AC commonly used.Voltate regulator 3 can adopt the Mg alloy surface of buying on the market that can provide to handle the voltate regulator of any model of required electric energy.Oxygen jet 7 is a tetrafluoroethylene with the material of treatment trough 9.MB8 magnesium alloy workpiece 5 need carry out oil removing, polishing and cleaning pre-treatment.

A kind of MB8 Mg alloy surface thickness of thin layer even processing method; Adopt the ac plasma differential arc oxidation treatment method that the MB8 magnesiumalloy is carried out surface treatment; Began in treatment solution, to spray into oxygen in preceding 1 minute 30 seconds carrying out surface treatment; And be that 1311～1313g/L, concentration of potassium hydroxide are that 359～361g/L, sodium silicate silicate are that 105～107g/L, power frequency ac voltage are that 47～49V, every liter of treatment solution oxygen straying quatity are under 0.006～0.009L/s condition in Potassium monofluoride concentration, the MB8 magnesiumalloy is carried out 62～82 seconds ac plasma Microarc Oxidation Surface Treatment.

Embodiment one; In Potassium monofluoride concentration is that 1311g/L, concentration of potassium hydroxide are that 359g/L, sodium silicate silicate are that 105g/L, power frequency ac voltage are that 47V, every liter of treatment solution oxygen straying quatity are under the 0.006L/s condition; After the ac plasma Microarc Oxidation Surface Treatment 62 seconds, can form the thick thin layer of the uniform 8 μ m of thickness at the MB8 magnesium alloy work-piece surface.

Embodiment two; In Potassium monofluoride concentration is that 1311g/L, concentration of potassium hydroxide are that 361g/L, sodium silicate silicate are that 107g/L, power frequency ac voltage are that 49V, every liter of treatment solution oxygen straying quatity are under the 0.006L/s condition; After the ac plasma Microarc Oxidation Surface Treatment 62 seconds, can form the thick thin layer of the uniform 9 μ m of thickness at the MB8 magnesium alloy work-piece surface.

Embodiment three; In Potassium monofluoride concentration is that 1313g/L, concentration of potassium hydroxide are that 359g/L, sodium silicate silicate are that 105g/L, power frequency ac voltage are that 47V, every liter of treatment solution oxygen straying quatity are under the 0.009L/s condition; After the ac plasma Microarc Oxidation Surface Treatment 82 seconds, can form the thick thin layer of the uniform 13 μ m of thickness at the MB8 magnesium alloy work-piece surface.

Embodiment four; In Potassium monofluoride concentration is that 1313g/L, concentration of potassium hydroxide are that 361g/L, sodium silicate silicate are that 107g/L, power frequency ac voltage are that 49V, every liter of treatment solution oxygen straying quatity are under the 0.009L/s condition; After the ac plasma Microarc Oxidation Surface Treatment 82 seconds, can form the thick thin layer of the uniform 14 μ m of thickness at the MB8 magnesium alloy work-piece surface.

Embodiment five; In Potassium monofluoride concentration is that 1311g/L, concentration of potassium hydroxide are that 359g/L, sodium silicate silicate are that 107g/L, power frequency ac voltage are that 49V, every liter of treatment solution oxygen straying quatity are under the 0.009L/s condition; After the ac plasma Microarc Oxidation Surface Treatment 82 seconds, can form the thick thin layer of the uniform 12 μ m of thickness at the MB8 magnesium alloy work-piece surface.

It is thus clear that; In Potassium monofluoride concentration is that 1311～1313g/L, concentration of potassium hydroxide are that 359～361g/L, sodium silicate silicate are that 105～107g/L, power frequency ac voltage are that 47～49V, every liter of treatment solution oxygen straying quatity are under 0.006～0.009L/s condition; The MB8 magnesiumalloy is carried out 62～82 seconds ac plasma Microarc Oxidation Surface Treatment, can form the thick protection thin layer of uniform 8～14 μ m of thickness at the MB8 Mg alloy surface.

Accompanying drawing 2 is the microtexture at the processing interface of adopting the inventive method that the MB8 magnesiumalloy is carried out to obtain after the surface treatment.The zone that the figure middle and upper part is light color is a resist, and it is the MB8 magnesium alloy substrate that the bottom is dark zone, and is visible, and the thickness of protection thin layer is very even.It is thus clear that the present invention can form thickness at the MB8 Mg alloy surface and protect thin layer uniformly.

Claims

1. MB8 Mg alloy surface thickness of thin layer even processing method; Adopt the ac plasma differential arc oxidation treatment method that the MB8 magnesiumalloy is carried out surface treatment; It is characterized in that; Began in treatment solution, to spray into oxygen in preceding 1 minute 30 seconds carrying out surface treatment; And be that 1311～1313g/L, concentration of potassium hydroxide are that 359～361g/L, sodium silicate silicate are that 105～107g/L, power frequency ac voltage are that 47～49V, every liter of treatment solution oxygen straying quatity are under 0.006～0.009L/s condition in Potassium monofluoride concentration, the MB8 magnesiumalloy is carried out 62～82 seconds ac plasma Microarc Oxidation Surface Treatment.