What Materials Are Solar Mounting Brackets Made of?—An Expert Analysis

Many people new to the solar industry often ask, “What materials are solar mounting brackets made of?” The choice of materials for solar PV mounting systems primarily involves striking a balance between strength, corrosion resistance, weight, and cost. Currently, steel dominates the market, accounting for over 90% of applications, while aluminum alloys and new composite materials each have their own specific use cases.

Essentially, selecting materials for PV mounting systems involves finding a balance between strength, durability, weight, and cost. Currently, steel holds over 90% of the global market share, making it the undisputed leader. Its core competitive advantage lies in its unparalleled mechanical strength, which allows it to easily withstand extreme weather conditions such as high winds and heavy snow, making it particularly suitable for large-scale ground-mounted power plants and mountainous projects. To resist corrosion, high-quality steel mounting systems undergo hot-dip galvanizing or are coated with a zinc-aluminum-magnesium alloy—a coating with even superior performance. This “armor” is key to ensuring a 30-year service life.

Analysis of Mainstream Mounting Materials
The vast majority of PV mounting systems on the market are made from one of two core materials: steel and aluminum alloy. Each has its own strengths and is suited for entirely different applications.

First, let’s look at steel, which is undoubtedly the king of ground-mounted power plants. Here, we specifically refer to corrosion-resistant carbon steel, most commonly hot-dip galvanized steel and the even higher-performance zinc-aluminum-magnesium steel. Steel’s overwhelming advantage lies in its unmatched mechanical strength. This allows it to easily withstand extreme loads such as high winds and heavy snow, while maintaining structural stability even in long-span installations. If you’re developing a megawatt-scale ground-mounted project, steel is the globally proven, most cost-effective choice.

Next, let’s look at aluminum alloy, which serves as the “light cavalry” for rooftop projects. Aluminum alloy has a density of only about one-third that of steel, a characteristic that allows it to excel on roofs with limited load-bearing capacity. Whether on factory buildings with color-coated steel roofing or flat concrete roofs, using aluminum alloy mounting brackets can significantly reduce safety risks to the building structure. At the same time, it possesses excellent corrosion resistance without the need for additional coating treatments, and its appearance is cleaner and more aesthetically pleasing. However, high strength and light weight also mean higher material costs.

Finally, let’s look at new materials: high-strength weather-resistant steel—a relatively new material with application cases still in the early stages of accumulation. It enhances corrosion resistance through its alloy composition and shows potential for weight reduction and cost savings in mountainous projects. Composite materials—whose technical standards have not yet been fully standardized—present technical challenges in joint connections and come with higher costs, though they are one-third lighter than aluminum and have already been applied in some European and American countries.

Corrosion Resistance and Scenario Suitability: The Two Cornerstones of Decision-Making
When faced with the choice between steel and aluminum alloys, first ask yourself two key questions: Where is the project located? How harsh is the environment?

If the project is on open, undeveloped land or farmland, go straight for high-quality galvanized steel. In this case, the focus shifts from “steel or aluminum” to “which corrosion-resistant coating to choose.” Traditional hot-dip galvanizing technology is highly mature; as long as the coating thickness meets standards (for example, an average thickness of no less than 65 micrometers in outdoor environments), it can provide effective protection for over 30 years. The new generation of zinc-aluminum-magnesium coatings goes a step further, featuring self-healing capabilities for scratches and enhanced corrosion resistance along cut edges, making it the preferred solution under current technological conditions.

If your project is located near a chemical plant, on coastal tidal flats, or in any environment with high humidity or high salt fog, corrosion protection becomes the top priority. In such scenarios, aluminum alloys are often less troublesome than ordinary steel because they are fundamentally resistant to rust. For certain critical components or offshore floating power stations, stainless steel may even be required to ensure absolute reliability. In short, be sure to select materials based on the climate and environmental data of the installation site.

The Most Fatal Pitfall When Purchasing
I have seen far too many projects that, in an effort to save a few cents per watt on mounting rack costs, ultimately paid a heavy price. This pitfall is—neglecting the product’s wind-resistance design and structural calculations.

There are always products on the market with extremely low quotes; they either cut corners by reducing the wall thickness of the profiles or simplify the structure of the connectors. These mounting systems may barely meet standards in laboratory static tests, but when faced with real-world typhoons, hurricanes, or sudden microbursts, their fragile joints can tear apart instantly, causing the entire array to be blown over or collapse. Overnight, millions in investment and years of power generation revenue can be wiped out. Not to mention that collapsing mounting systems may damage roofs or cause injuries or fatalities. Please remember: A mounting system rigorously tested in wind tunnels and validated through structural mechanics calculations is the most important form of insurance you can purchase for your power plant.

Choose Yiteng: Safeguarding Long-Term Value Through Engineering Excellence
In the face of a complex international market and inconsistent product quality, choosing a reliable partner is crucial. As a global leader in photovoltaic mounting systems, Yiteng’s core strength lies in providing one-stop, highly adaptable solutions. We have a team of top-tier structural engineers who can provide customized wind and snow load calculations based on the specific meteorological data of your project site. Our product line covers a full range of materials—from zinc-aluminum-magnesium steel and aluminum alloys to stainless steel—all of which have passed rigorous international certifications such as TÜV and CE. When you choose Yiteng, you’re not just buying mounting systems; you’re purchasing a commitment—backed by world-class engineering expertise—to the stable operation of your power plant for the next 30 years.

Frequently Asked Questions (FAQ)
1. For large-scale ground-mounted solar power plant projects, which is more cost-effective: steel or aluminum alloy?
Steel is undoubtedly the more cost-effective choice. For the same load-bearing capacity, the material and processing costs of galvanized steel are significantly lower than those of aluminum alloy, making it particularly suitable for scenarios requiring large spans and tall support structures.

2. How can you quickly assess the corrosion protection quality of a batch of steel mounting structures?
The most direct method is to test the coating thickness on-site. For hot-dip galvanized components, use a coating thickness gauge to ensure the average zinc layer thickness at critical locations is no less than 65 micrometers. At the same time, inspect the surface for any areas with missing zinc coating, bubbles, or burrs.

3. Do aluminum alloy mounts never rust at all?
Aluminum alloy does not develop red rust like steel does, but the naturally formed oxide film on its surface may be damaged in strongly alkaline or high-chloride environments. Therefore, when using aluminum alloy for coastal projects, it is recommended to select models that have undergone anodizing or powder coating.

4. Why is the structural calculation report more important than the product price?
Because photovoltaic mounting systems are custom-engineered structural products. A detailed structural calculation report demonstrates that the supplier has conducted rigorous calculations based on your local wind speeds, snow loads, and geological conditions—this is the core evidence of the product’s safety.

5. When purchasing mounting systems, what technical terms should be clearly specified in the contract?
The contract must clearly specify the material grade, the type and minimum thickness of the corrosion-resistant coating, the load standard used in the design (e.g., ASCE 7-22), and the deliverables the supplier is required to provide (including structural calculation reports, material certificates, and installation instructions).