Aluminum pot hard anodizing

Hard anodizing plating line

Hard anodizing plating line:

Hard anodizing plating line

Hard anodizing plating line

Hard anodized aluminum main purpose is to improve variety performance of aluminum and aluminum alloys, including corrosion resistance, abrasion resistance, weather resistance, insulation and absorption and so on. It applies to the deformation of aluminum alloy, and it may also be used for pressure casting aluminum parts. Mostily we know it is perfect of aluminum pot manufacturer.

Hard anodizing full name and hard anodization treatment.

Hard anodizing plating line technical method:

Hard anodizing electrolytic has many ways, such as: sulfuric acid, oxalic acid, propylene glycol, sulfosalicylic acid and other inorganic salts and organic acids. Thepower supply can be divided into DC rectifier, AC power supply, AC-DC superimposed anodizing rectifier, superimposed pulse and pulse power supply and so few, the widely used as below:
(1) Sulfuric acid hard anodic oxidation.
(2) Oxalic acid hard anodic oxidation.
(3) Mixed acid type hard anodization.
Among them, sulfuric acid is to be more widely applied for hard anodizing plating line.

Aluminum pot hard anodizing

Aluminum pot hard anodizing

Alunimun hard anodization

Alunimun hard anodization

Hard anodizing plating line working principle:

Pure sulfuric acid type hard anodizing general principles compare with normal oxidation is no essential difference, if it is a mixed acid type will have attachedreaction. The reaction is essentially:
1. Cathode reaction:
4H + + 4e = 2H2 ↑
2. Anode reaction:
4OH – - 4e = 2H2O + O2 ↑
3. Aluminum oxidation: the anode precipitated oxygen at the atomic state, more active than molecular state, more likely to react with the aluminum:
2A1 + 3O → A12O3

Hard anodizing plating line characteristic:

Electrolysis act at a temperature of -10 ℃ ~ + 5 ℃ electrolyte. Because hard anodizing the resulting oxide film having a higher resistance to oxidation will directly affect the strength of the current. In order to obtain a thick oxide film, need to increase the external voltage, its purpose is to eliminate the large resistance impact, making the current density to keep constant, but when current large will produce intense heat phenomenon, together with large heating when producing anodizing film will release a lot of heat, so that workpiece temperature increasing temperatures will accelerate the dissolution of the oxide film, the oxide film can not be thickened.
Solution: use our special design hard anodizing plating line and rectifier.

Stainless steel electrolytic polishing

Stainless steel electrolytic polishing

Stainless steel electrolytic polishing:

Stainless steel electrolytic polishing machine mainly for stainless steel parts surface brightness treatment. Stainless steel electro polishing use workpiece as an anode, insoluble metal as cathode, 2 poles immersed in the bath at the same time, with direct current to generate selective anodic dissolution, the workpieces surface will gradually leveling, so as to increase surface brightness effect.

Rectifier: 3 phase 380V, rectifier current, according to customer workpiece size. Operating voltage 8-20v.

Stainless steel electrolytic polishing principle:

Stainless steel electrolytic polishing major recognized theory is mucosal theory. Which is: the metal ion break away from workpiece with phosphoric acid form a layer of phosphate film adsorbed on workpieces surface, this mucous membrane is thinner in the projections while thicker in recess, because the projections high current density then dissolved quickly, with the mucous membrane fluidity, changing irregularities, the roughened surface is gradually become leveling process.

Stainless steel electro polishing advantages:

⑴ Same color of inside and outside, gloss retention, mechanical polishing can not get the recess be leveled.
⑵ High production efficiency, low cost.
⑶ Increase surface corrosion resistance, suitable for all stainless steel.

Stainless steel electroplating polishing conditions required:

Power waveform requirements are not strict, can choose of SCR type or high frequency plating rectifier.

Electropolishing tank and mating facilities (anode rod):

Hard PVC plates welded together. Bath top 3 electrode rods, the middle of movable anode rod, then connect with anode (or positive), both sides as cathode pole, connect with power cathode (negative).

Facilities of heating and cooling equipment:

① Heating can use quartz heating tube, or titanium heating tube.
② Cooling can use coil tube, heating coil can heat and cool.

Stainless steel polishing machine hanger:

It is best to select titanium hanger, because titanium is more resistant to corrosion, long serve life, titanium ions has no effect on the bath. It is suggested not to use copper hanger, because when copper ions into stainless steel surface will generate a layer of bad bonding force copper layer, then impact the polishing quality.

Anode and cathode materials:

Cathode and anode rods adopt copper or brass, brass tube length plus 20cm longer than electrolytic bath, cathode plate use lead plate, fixed to the cathode rod, height plus 10 cm than tank height, lead plate width decided according to bath length, generally 10cm, 20cm.

Stainless steel polishing machine mainly for stainless steel parts surface brightness treatment. Stainless steel workpiece are 200 series, 300 series, 400 series material, each serie has the targeted electro polishing chemical solution.

Stainless steel electrolytic polishing process: degreasing – washing – anti rust – washing – electrolytic polishing – washing – passivation – packaging.
Stainless steel electrolytic polishing

Stainless steel electrolytic polishing

Hard oxidation

Hard oxidation and ordinary oxidation difference: Hard anodized oxide film has 50% penetration inside the aluminum products, an another 50% attached to the aluminum workpieces surface, so after a hard anodizing exterior of the product size becomes bigger, the hole becomes smaller, while after hard oxidation the external dimensions of ordinary oxidation becomes smaller and the hole becomes bigger.

Hard oxidation colors:

Hard oxidation colors usually made of black and oxidation film true colour (natural color), true color is determined by the aluminum alloy composition, even the same type of aluminum ( for example 6061-T6), and different manufacturers, the color of the oxide film is different, if Aluminum use same manufacturer the same type of material maybe colors are different, and therefore, the true nature of the oxide film is generally used for the internal parts of the product.

Hard oxidation aluminum advantages:

1, Aluminum hard anodizing surface hardness can even up to HV500, which can compare to chrome plating;
2, The hard anodizing film thickness from 25 to 250um;
3, Have features of strong adhesion, according to the generated hard anodized oxidation characteristics: hard oxidation film has a 50% penetration in aluminum inside,
50% adhered to the surface of an aluminum alloy;
4, Good insulation: breakdown voltage up to 2000V;
5, Great wear resistance: for if copper content more than 2% in aluminum alloy, its maximum wear index of 3.5mg/1000rpm. All other alloys wear index should not exceed than 1.5mg/1000rpm;
6, Non-toxic: the oxidation film and for anodic oxide film produced by an electrochemical process there is no toxic to humans.

So now a lot of industry in order to facilitate machining and reduce the weight of products, and environmental protection requirements, some hard oxidation aluminum alloy parts products are currently to replace stainless steel, and conventional spray, plating treatment process.

Hard oxidation real case:

This customer use our Hard oxidation pulse power supply for aluminum pot hard oxidation, the result is very good. You can see the below surface, the hardness also very good, there is no any scratch on surface even use a knife to cut the aluminum pot hard anodizing surface.

2000A90V Hard oxidation rectifier, using our power supply you can get very good treatment even 2 & 7 series aluminum grade.

Oxidation pulse power supply

Oxidation pulse power supply

Hard oxidation pot using our pulse rectifier

Hard oxidation pot using our pulse rectifier

Hard oxidation pot using our pulse power supply

Hard oxidation pot using our pulse power supply

Copper plating line

Copper plating line

Copper plating line

Copper plating line products

Copper plating line process:

Electroless copper plating line is a process for printed circuit board manufacturing, often called sink-copper or PTH, which is a self-catalytic redox reactions. First treatment with activator agent, adsorbed on insulating substrate layer surface of active particles usually as metal palladium particles (palladium is a very expensive metal, the price is high and has been rising, to reduce cost now practical colloidal copper process is in the application), copper ions are first reduced on these active palladium metal particle, which these reduced metal copper nuclei itself has become a copper ion catalyst layer, so that copper reduction proceed on these new copper nuclei surfaces.

Electroless copper plating: traditional copper plating mostly as vertical lines, process are similar, the general process is:
Cleaning → Neutralization → Degreasing → Microetching → Pre-ditching → Activation → Chemical copper plating.

The main components are cathode and anode in copper plating line:

Cathode: giving rise to the starting & end a couple of stainless steel rod having a pair of electrical contact ring, copper brush is pressed against the copper ring in order to get good contact, connected to the negative pole of rectifiers. By retaining roller, the cathode cut off contact with plating solution.
Copper plating line anode: 2 titanium plate installed in plating bath, these two anode pieces connect with positive rectifies pole by electricity cable directly. Anode soaked in chemical plating solution.

Chemical copper plating line principle:

Electroless copper plating on the surface of the catalytic activity by the action of a reducing agent to precipitate the copper ions reduced:
Reduction (cathode) reactions: CuL2 + + 2e- → Cu + L
Oxide (anode) reaction: R → O + 2e-
Thus, with hypophosphite as a reducing agent for chemical copper plating main reaction is: 2H2PO2- + Cu2 + + 2OH- → Cu + 2H2PO3 + H2 ↑
In addition to the establishment of the thermodynamics, chemical reactions must also meet dynamics conditions. Like other chemical copper as the catalytic reaction thermal energy is required to cause a reaction, which is why only when the chemical bath plating deposition get speed plating under certain temperature. Theoretically copper plating speed to express by increasing the concentration of the reaction product of reactant concentrations and reduce the speed. In actual use, the electroless copper plating solution containing certain additives, its have too many factors to effect, the situation becomes too complicated. Thus, most of the electroless copper plating dynamics research is limited to the most basic component of the bath at the start.

And copper plating line rectifiers normally as following specification:

Rectifiers for Copper Plating Line

Rectifiers for Copper Plating Line

Copper plating chrome machine

Copper plating chrome machine

The nature of the chromium and copper plating chrome machine usage:

1, Chrome nature: Chromium is a microstrip blue silver-white metal, in the air easily passivation, formed a very thin film layer on surface, and therefore able to maintain the long original luster in the atmosphere, show noble metal properties. Chrome and sulfuric acid, nitric acid, and many organic acid have no chemical effects, but can be dissolved in hydrohalic acids (e.g. hydrochloric acid), and hot sulfuric acid.

2, Copper plating chrome machine usage:

  • Protective and Decorative chrome plating: On the polished coating film layer, chrome plating or bright chrome plating (bright copper or brightness nickel) of 0.25 ~ 2μm copper plating chrome machine film plating, can make products more bright surface, and has a certain degree of wear resistance, heat resistance, which has been widely used in bicycles, watches and other industrial production. At the same time, also could be used for the mirror, because the anti sulfide performance of chrome plating coating layer is stronger than the silver plated layer.

    Copper plating chrome machine products get high hardness:

  • Wear-resistant chromium (hard chrome plating of copper plating chrome machine) on steel base plating anti-wear chrome, chrome plated hardness can up to 850 ~ 1200HV, with high wear resistance, that is widely used measuring tools, cutting tools, a variety of machine axes class and other machine parts manufacturing.
  • Black chrome: On some instrument or sophisticated equipment, in order to prevent the reflection of some parts to plate black chrome on it.
  • Loose hole chrome plating machine: with good lubrication and wear resistance, mainly used for cylinder internal combustion engine, cylinder liners, piston rings, crankshaft and other parts.

3,  Copper plating chrome machine type according to the decorative classification:

(1) Brightness copper plating chrome machine;
(2) General chrome (loose hole chrome plating);
(3) Cream chromium;
(4) Black Chrome.

Copper plating chrome machine

Copper plating chrome machine

Copper plating chrome machine

Copper plating chrome machine

Copper plating chrome machine

Copper plating chrome machine