Why is iron oxide so popular in construction? https://www.ironoxidered.com/recommend-products/concrete-colour ...    More ...

Why is iron oxide so popular in construction?
https://www.ironoxidered.com/recommend-products/concrete-colour-oxide-supplier.html          
 
Iron oxide pigments                produce rich, long-lasting color in concrete and other cementitious materials. This pigment has five basic components that explain it:
Good weathering resistance.
good light resistance.
Excellent resistance of concrete to alkaline environments
tinting power (hence vibrant colors).
Fine dispersion
This means that iron oxide pigments do not deteriorate over time through a variety of irritations such as rain, extreme UV exposure and shoe rubbing. Therefore, it is assumed that a good and long-lasting color for concrete can be achieved with just one iron oxide.     
 
How to use iron oxide pigment in concrete
The amount of iron oxide pigment in concrete products is limited to 1% to 10%. Exceeding the upper limit will reduce the mechanical strength of the products. Generally 5%～8% is appropriate.     
Iron oxide pigment does not contain two compounds, lead oxide and zinc oxide, which will affect the setting time and strength.
Sometimes, concrete products need to be cured at temperatures and pressures above 200°C. Therefore, black iron oxide and brown iron oxide, which can be converted to red iron oxide at 180°C, must be heat stabilized.     
Cement concrete pavement mixed with iron oxide pigment should not be too thick at one time. Generally not more than 20cm. too thick will cause the waste of iron oxide pigment for concrete, which is not economical and cannot guarantee the quality of concrete itself.     

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