Zinc phosphate (Zn3(PO4)2)
is an inorganic chemical
compound used as a corrosion resistant
coating on metal surfaces.
Phosphate salts is applied via spraying or immersion and chemically reacts with the surface of the part being coated to form a layer of insoluble, crystalline phosphates. Normal operation pH : 2.6 - 3.0
The operation should be controlled, to make best result :
- Temperature (if use Hot Temperature)
- Time
- pH
- Product concentration
- Free and Total Acid
--Total acid is measure of total bath concentration/ Zn Content
--Free Acid is maintain Zn solubility
--Free Acid is maintain Zn solubility
The other chemicals should be add in Zinc Phosphating are :
- Accelerator (Dia Toner 20)
- Neutralizer (Dia Starter 40 - maintain pH, Free acid)
Advantage :
- Coating thickness 2.000 - 10.000 nm (usually 1.5 - 2.5 g/m2)
- High corrosion protection
Quality requirements on phosphate coating prior to painting :
- Uniform, small crystal
Optimum process sequence of phosphating in Customer, spray application :
Coating after treatment with phosphating:
Crystal view with SEM (Scanning Electron Microscopy), aplication via spray, material steel :
I. Zinc Phosphate, 3 kation (Spray application):
Our Product : Diafos 1000 Prep (Make Up), Diafos 1000 Alim (Replenishing)
Packaging : DF 1000 Prep (25 Kg/can), DF 1000 Alim (28 Kg/can)
DIAFOS 1000 is a nitrite accelerated tricationic
phosphating process for steel, galvanized and alloy coated (Zn/Ni) steel. It
generates a fine crystalline coating of manganese containing zinc phosphate. The
crystalline layer has very good rust protecting properties and is an excellent
support for subsequent painting or organic coating. DIAFOS
1000 gives particularly good results for steel in combination with
galvanized or hot dip galvanized steel.
Optimum process sequence of phosphating in Customer, spray application :
a. Degreasing
Product : Diaclean M-140 or Diaclean H-435
Concentration : 2 - 5%
Temperature : 40 - 60°C
Contact Time : 2 - 10 minutes (depending on the oil)
b. Rinsing, prevent contamination
Product : City water
Temperature : Room Temperature (RT), ambien
Contact Time : 1 - 2 minutes
c. Activation (Surface conditioning)
Product : Dialene 80
Concentration : 0.1 - 0.2%
Temperature : Room Temperature (RT), ambien
Contact Time : 1 - minutes
d. Phosphating
Product : Diafos 1000 Prep (Make Up) Alim, Diafos 1000 Alim
(Replenishing)
Concentration : 3 - 5%
Temperature : 45 - 50°C
Contact Time : 2 - 15 minutes (depending on the thickness)
e. Rinsing, (prevent contamination)
Product : City water
Temperature : Room Temperature (RT), ambien
Contact Time : 1 - 2 minutes
f. DI Water Rinsing, (prevent contamination)
Product : Demineralize water (DI Water)
Temperature :Room Temperature (RT), ambien
Contact Time : 1 - 2 minutes
Proses:
Degreasing -- Rinsing -- Surface Conditioning -- Phosphating -- Rinsing -- DI Water Rinsing
Proses:
Degreasing -- Rinsing -- Surface Conditioning -- Phosphating -- Rinsing -- DI Water Rinsing
Coating after treatment with phosphating:
Crystal view with SEM (Scanning Electron Microscopy), aplication via spray, material steel :
Magnification 1000x, appearance : oval
crystal, small size, uniform particles
For more details, please contact us :
PT. Aalen Chemicals Indonesia
Jl. Pulobuaran III Blok G3,
Kawasan JIEP Pulogadung
Tlp : 021-46830522
Website : www.aalen.co.id
Email : aalen.chemicals@gmail.com, aalen@cbn.net.id
Website : www.aalen.co.id
Email : aalen.chemicals@gmail.com, aalen@cbn.net.id
1 comment:
Thank you for sharing such a knowledgable post. Zinc phosphate is the best alternative for zinc chromate and red lead which are highly toxic and above all it provides a good corrosion resistance. Well, keep up the good writing.
Post a Comment