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Life of iron-phosphating if remain uncoated further

2005

Our process require zinc rich primer coating on mating surface before part assembly in welding shop. When we do iron-phosphate spray coating prior to zinc rich primer on require area , over-spray on nearby area cause rust formation (particularely in monsoon season), as our next procedure is main pre-treatment line (zinc phosphate ) which take place after 03 days when car body take shape and shift to paint shop.
My question is that how long we can maintain ironphosphating "rustfree" without any further treatment.

Saurabh Sharma
Painting - Indore , M.P. India

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2005

Hi Saurabh,

The answer to your question is, "It depends." It depends on the environment in which the parts are stored, it depends on the type of phosphate coating, it depends on the nature of the metal substrate.

In general, iron phosphate coatings do not provide a high degree of stand-alone rust protection. Phosphated surfaces afre meant to be painted as soon as possible after pretreatment.

George Gorecki
- Naperville, Illinois

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Paint within 24 hours of iron phosphating.

Sheldon Taylor
supply chain electronics
Wake Forest, North Carolina
2005

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Hello Mr Saurabh;

Try choosing Tri-Cationic phosphating instead of iron phosphate and for Gods sake do an excellent phosphating.
My process lasts me up to six days before we CED Coat which is similar to your car body process. Mask the areas you don't want to phosphate.

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

2005