Thermal expansion and contraction effect: Corten steel, like all metals, expands when heated and contracts when cooled. In high-temperature environments (e.g., surface temperature exceeding 60℃ under strong sunlight), the signboard will have slight thermal expansion; if the temperature drops sharply (such as sudden rain after sun exposure), uneven cooling may cause tiny internal stresses, leading to subtle warping in thin plates (≤3mm). However, Corten steel's alloy composition gives it good structural stability, and this deformation is usually within the range of aesthetic and functional tolerance and will not cause overall structural damage.
Thickness and structural design determine the degree of deformation: For thick Corten steel signboards (≥5mm) with reasonable structural supports (such as back framing or reinforcing ribs), the thermal deformation will be almost negligible because the thickness and support structure enhance rigidity and disperse thermal stress. Thin plates without reinforcement are more prone to slight deformation under prolonged sun exposure.
No accelerated deformation due to corrosion: Unlike ordinary steel, Corten steel forms a dense protective rust layer that does not cause structural strength loss in high-temperature and sun-exposed environments, so it will not have deformation caused by corrosion-induced strength reduction.
Optimize thickness selection: Choose plates with a thickness of ≥3mm for outdoor signboards, and add aluminum alloy or steel reinforcing ribs to the back of large-area signboards (over 1㎡) to improve structural rigidity.
Rational installation design: Leave a small gap between the signboard and the mounting bracket to accommodate thermal expansion and contraction, avoiding rigid fixation that restricts metal movement and causes stress deformation.
Surface treatment: Apply a layer of transparent UV-resistant protective glaze on the surface of the signboard. While not affecting the formation of the rust layer, it can reduce direct UV radiation and slow down the temperature rise of the steel plate, thereby mitigating thermal deformation.
