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Zinc Metal Paint has high zinc loading (98% in the dry film) and unique binder intensify thisgalvanic action. As a consequence Zinc Metal Paint-coated jobs last longer saving costly labor and costs associated with recoating.It is commonly used by original equipment manufacturers (OEM's) as in plant substitute for hot-dip galvanizing.The corrosion is prevented by the formation of electrochemical cell commonly known as voltaic cell. To know how it works and how Zinc Rich fulfills all it's requirements let us first see theprinciple.The Principles of Galvanic Protection (COLD GALVANIZING)When a steel is coated with Zinc metal spray it forms a electrochemical cell (commonly known asVoltaic or Galvanic cell). A galvanic cell requires three elements 1. Two electrochemically dissimilarmetals, 2. An electrically conductive path between the two metals, 3. an electrolyte to allow the flow of metalions. In this case Iron & Zinc become electrodes and the atmospheric moisture becomeselectrolyte. In electrochemical cell electrons are given out at one of the electrodes called anode(process known as oxidation) and gained by the other electrode called cathode (process known asreduction). This redox process i.e. reduction and oxidations proceed simultaneously and electron flowfrom anode to cathode. The potential difference between two metals is responsible for this flow ofcurrent. The current flows from an electrode of higher potential to the electrode of lower potential.This is the electromotive force (emf). In electro motive series Zinc is higher than Iron or Steel(Standard electrode potential of Zn = +0.7628 Eo & Fe= +0.4402 Eo) and hence Zinc becomes anodeand steel a cathode. The atmospheric moisture acts as an electrolyte and when the reaction starts Zincundergoes oxidation to give Zn++ ions which pass into water where they either stay in solution or reactwith other ions in the electrolyte. In short in the presence of moisture, the electrochemical processstarts between the zinc which is an anode and the steel or iron , the underlying substrate which iscathode Corrosion attacks the zinc, leaving the base metal unaffected Zinc, being higher in theelectro-motive series than iron or steel, is more susceptible to corrosive attack. Thus, in the presenceof an electrolyte (moisture), zinc will preferentially sacrifice itself to protect the steel. Zinc ions gointo solution, liberating electrons which cause a current flow into the steel, thereby preventing ferrousions from going into solution and beginning the electrochemical corrosion cycle. This process isknown as galvanic corrosion and the protection of steel is known as Galvanic protectionZinc Metal Spray (ZMS) fulfills all the requirements as per most demanding internationalstandards to provide a coat that affords true Galvanic protection to steel.1. Pure Zinc rich flakes produced by condensation of purified zinc vapours is used in ZMS whichare spherical shaped fine particles. These discrete spheres of zinc dust which are packed closeenough together ensures a virtual tangential contact between the zinc particles and the steelsubstrate which is absolutely necessary for contacting the electrical corrosion current for forming galvanic cell.2. To function anodically, the zinc particles must be in intimate contact with one another so thatthe film itself is conductive. This is achieved in ZMS by the high zinc loading mixed in aspecial binder that does not insulate the zinc particles either from each other or from the basesubstrate.This illustration shows the difference between the true galvanic protection of ZMSand other types of coatings. The difference is made possible by high zinc content ( more than93% to 96% by weight in the dried film) and proprietary, non-encapsulating binder. This uniquecombination provides a self healing galvanic film.3. The protection afforded by ZMS is twofold; cathodic protection and barrter protection. Initially, the protection provided by Zinc Metal Paint Is wholly that of galvanic action.