Stone Coated Metal Roof Tiles Hot Sale

Zinc-Aluminum-Magnesium Alloy Substrate
Premium stone chip tiles increasingly utilize advanced Zinc-Aluminum-Magnesium (ZAM or Zn-Al-Mg) coated steel substrates, representing a metallurgical evolution beyond standard galvanization. This alloy coating—typically comprising 90-95% zinc, 4-10% aluminum, and 1-3% magnesium—forms a complex multi-phase microstructure (Zn/Al/MgZn2 eutectics) that provides superior sacrificial protection through "smart" self-healing mechanisms. When scratched, magnesium hydroxides and aluminum oxides rapidly form a dense, insoluble barrier layer that seals the exposed steel, while zinc continues cathodic protection. The aluminum component enhances fluidity during hot-dip coating, yielding smoother surfaces with fewer spangles (visible zinc crystals), critical for uniform paint adhesion. ZAM coatings demonstrate 5-10x better corrosion resistance than standard G90 galvanization in cyclic corrosion tests (e.g., ISO 14993), particularly excelling in chloride-rich coastal or de-icing salt environments where traditional zinc suffers rapid depletion.

The practical implications of ZAM substrates are transformative for roof integrity. In cut-edge protection tests (ISO 17718), ZAM exhibits less than 0.5mm creepage after 1,000 hours salt spray versus 3-5mm for galvanized steel, drastically reducing rust-jacking risk at sheared tile edges. The alloy's micro-hardness (≈150 HV) resists installation abrasion better than pure zinc (≈70 HV). Crucially, ZAM's "barrier-dominated" corrosion mechanism prevents the voluminous white rust that can delaminate coatings on standard galvanized steel in humid conditions. This allows for thinner coating weights (e.g., 150g/m² ZAM outperforms 275g/m² pure zinc) while reducing tile weight by 8-12%. The smoother surface also enhances stone granule adhesion strength by 15-20% in peel tests (ASTM D903). For projects in corrosive industrial/marine environments or demanding 60-year warranties, ZAM substrates provide an engineering margin of safety unattainable with conventional materials, often eliminating the need for supplemental cut-edge sealants.

FAQ

Q: Are you trading company or manufacturer?

A: We are an industrial and trade company integrating production and sales, factory is located in Shandong Province, and in response to the new Free Trade Port policy, a trading company has be established in Hainan- FUODE.

Q: Do you provide samples? Is it free or extra?

A: Feel free to request small side samples or larger-sized samples for free by your freight collected number, allowing you to thoroughly evaluate the quality of our products before making a decision.

Q: Do you accept the third party inspection?
A: Yes, our products can be accept any third party to test the quality, and If the customer has any requirements, we can also accept the third-party testing before shipment.

Q: How could you guarantee your products?
A: Our quality management is according to the ISO9001 system, and the products has been passed CE, SGS, COC inspection

Q: Accepted terms of delivery?
A: We accept EXW FOB CFR CIF etc., you can choose the one which is the most convenient or cost effective for you.

Q: How long is the stone coated tile’s service time?
A: The evenly coated aluminum steel plates on both sides are the key to the long lifespan of the tiles. The color persistence of the tiles depends on the quality of the sand used. We can provide tiles of different qualities ranging from 10 years ~ 50 years according to customer requirements.

Q: What’s the MOQ?
A: The thickness 0.18~0.50mm is 500pcs/ style/color/thickness

   The thickness 0.51~0.60mm is 200pcs/ style/color/thickness

Q: How long is your delivery time? 

A: Generally it is 7~15 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.