Method for preparing black ceramic membrane by magnesium alloy differential arc oxidation

Abstract

The invention relates to a method for preparing a magnesium alloy micro-arc oxidating black ceramic film which belongs to the magnesium alloy surface treating technique field. Blue copperas metal cation Cu(2+) is used as a coloring additive that is added into an alkali basic electrolyte with sodium silicate as main salt after being complex by complexing agent ammonia, an electrical parameter suitable to the electrolyte is set for micro-arc oxidating and coloring, various electrolyte has various coloring effect to film, the ceramic film color is determined by metal oxidation of film or structure composed by the salt and silicate. Sodium silicate prepares black ceramic film on the magnesium alloy surface as main salt. The black ceramic film obtained by the magnesium alloy micro-arc oxidating has better corrosion resistance and hardness, and has characteristics of uniform color, high black degree. The method has widely application prospect.

Description

technical field

[0001] The invention belongs to the technical field of magnesium alloy surface treatment, and relates to a method for preparing a magnesium alloy micro-arc oxidation (MAO) black ceramic film. technical background

[0002] Magnesium is the lightest metal among structural materials, its specific gravity is 2 / 3 of aluminum and 1 / 4 of steel. Magnesium alloys have many excellent properties. The specific strength of cast magnesium alloys is higher than that of aluminum alloys and steels. The specific stiffness of forged magnesium alloys is comparable to that of aluminum alloys and steels. Its machinability, electrical conductivity, and thermal conductivity are excellent. far superior to aluminum alloys. It has good low-temperature performance, superconductivity and hydrogen storage performance, can be recycled and reused, and has little pollution to the environment. Due to these excellent properties of magnesium alloy, it is known as the "green engineering materi...

Examples

Embodiment 1

[0040] I. The reagents used are:

[0041] The main film-forming agent is sodium silicate, the chemical formula is: Na 2 SiO 3 9H 2 O,

[0042] The film-forming auxiliary agent is potassium fluoride, the chemical formula is: KF·2H 2 O,

[0043] The pH regulator is potassium hydroxide, the chemical formula is: KOH,

[0044] Complexing agent B: ammonia water,

[0045] Colorant A: copper sulfate pentahydrate,

[0046] II. The equipment used is:

[0047] MAO120HD-II micro-arc oxidation device developed by Xi'an University of Technology. The device is mainly composed of power supply and control system, oxidation tank, stirring system and cooling system.

[0048] The rare earth magnesium alloy material is: SJDM-1 rare earth magnesium alloy; the main composition (W%) is shown in Table 1.

[0049] Table 1 SJDM-1 rare earth magnesium alloy chemical composition (Wt%)

[0050]

[0051] III. Preparation of MAO coloring treatment solution

[0052] First take distilled water a...

Embodiment 2

[0065] 1, the reagent used is with embodiment 1.

[0066] II, the equipment used is as embodiment 1.

[0067] The rare earth magnesium alloy material is as in Example 1.

[0068] III. Preparation of MAO coloring treatment solution

[0069] First take distilled water and pour it into the equipment, add reagents at room temperature, the order and concentration range of reagents are: sodium silicate (Na 2 SiO 3 9H 2 O) is 7g / L, potassium fluoride (KF 2H 2 O) is 7g / L, and potassium hydroxide (KOH) is 8g / L, constantly stirs during adding, treats that a kind of reagent dissolves fully and then adds another kind of reagent, after adding, stir until reagent dissolves completely; After dissolving 2.2g of coloring agent A in water, add complexing agent B to make the concentration 45ml / L, let it stand for 10min-30min, then add it into the prepared solution above, and continue to stir until it is evenly mixed.

[0070] IV. Implementation of MAO process

[0071] 1) Degreasing and cl...

Embodiment 3

[0082] 1, the reagent used is with embodiment 1.

[0083] II, the equipment used is as embodiment 1.

[0084] The rare earth magnesium alloy material is as in Example 1.

[0085] III. Preparation of MAO coloring treatment solution

[0086] First take part of the distilled water and pour it into the equipment, then add the reagents at room temperature, the order and concentration range of the reagents are: sodium silicate (Na 2 SiO 3 9H 2 O) is 8g / L, potassium fluoride (KF 2H 2 O) is 7g / L, and potassium hydroxide (KOH) is 7g / L. Stir continuously during the addition process. After one reagent is completely dissolved, add another reagent. After adding, stir until the reagent is completely dissolved; dissolve Add colorant A to make the concentration 2.6g / l, add B to make the concentration 50ml / L, let it stand for 10min-30min, then add it to the prepared solution above, and continue to stir until the mixture is uniform.

[0087] IV. Implementation of MAO process

[0088] 1) ...

technical field

[0001] The invention belongs to the technical field of magnesium alloy surface treatment, and relates to a method for preparing a magnesium alloy micro-arc oxidation (MAO) black ceramic film. technical background

[0002] Magnesium is the lightest metal among structural materials, its specific gravity is 2 / 3 of aluminum and 1 / 4 of steel. Magnesium alloys have many excellent properties. The specific strength of cast magnesium alloys is higher than that of aluminum alloys and steels. The specific stiffness of forged magnesium alloys is comparable to that of aluminum alloys and steels. Its machinability, electrical conductivity, and thermal conductivity are excellent. far superior to aluminum alloys. It has good low-temperature performance, superconductivity and hydrogen storage performance, can be recycled and reused, and has little pollution to the environment. Due to these excellent properties of magnesium alloy, it is known as the "green engineering materi...

Examples

Embodiment 1

[0040] I. The reagents used are:

[0041] The main film-forming agent is sodium silicate, the chemical formula is: Na 2 SiO 3 9H 2 O,

[0042] The film-forming auxiliary agent is potassium fluoride, the chemical formula is: KF·2H 2 O,

[0043] The pH regulator is potassium hydroxide, the chemical formula is: KOH,

[0044] Complexing agent B: ammonia water,

[0045] Colorant A: copper sulfate pentahydrate,

[0046] II. The equipment used is:

[0047] MAO120HD-II micro-arc oxidation device developed by Xi'an University of Technology. The device is mainly composed of power supply and control system, oxidation tank, stirring system and cooling system.

[0048] The rare earth magnesium alloy material is: SJDM-1 rare earth magnesium alloy; the main composition (W%) is shown in Table 1.

[0049] Table 1 SJDM-1 rare earth magnesium alloy chemical composition (Wt%)

[0050]

[0051] III. Preparation of MAO coloring treatment solution

[0052] First take distilled water a...

Embodiment 2

[0065] 1, the reagent used is with embodiment 1.

[0066] II, the equipment used is as embodiment 1.

[0067] The rare earth magnesium alloy material is as in Example 1.

[0068] III. Preparation of MAO coloring treatment solution

[0069] First take distilled water and pour it into the equipment, add reagents at room temperature, the order and concentration range of reagents are: sodium silicate (Na 2 SiO 3 9H 2 O) is 7g / L, potassium fluoride (KF 2H 2 O) is 7g / L, and potassium hydroxide (KOH) is 8g / L, constantly stirs during adding, treats that a kind of reagent dissolves fully and then adds another kind of reagent, after adding, stir until reagent dissolves completely; After dissolving 2.2g of coloring agent A in water, add complexing agent B to make the concentration 45ml / L, let it stand for 10min-30min, then add it into the prepared solution above, and continue to stir until it is evenly mixed.

[0070] IV. Implementation of MAO process

[0071] 1) Degreasing and cl...

Embodiment 3

[0082] 1, the reagent used is with embodiment 1.

[0083] II, the equipment used is as embodiment 1.

[0084] The rare earth magnesium alloy material is as in Example 1.

[0085] III. Preparation of MAO coloring treatment solution

[0086] First take part of the distilled water and pour it into the equipment, then add the reagents at room temperature, the order and concentration range of the reagents are: sodium silicate (Na 2 SiO 3 9H 2 O) is 8g / L, potassium fluoride (KF 2H 2 O) is 7g / L, and potassium hydroxide (KOH) is 7g / L. Stir continuously during the addition process. After one reagent is completely dissolved, add another reagent. After adding, stir until the reagent is completely dissolved; dissolve Add colorant A to make the concentration 2.6g / l, add B to make the concentration 50ml / L, let it stand for 10min-30min, then add it to the prepared solution above, and continue to stir until the mixture is uniform.

[0087] IV. Implementation of MAO process

[0088] 1) ...

Images