295MPa Q295NH Weather Resistant Steel is a premium low-alloy material designed for critical heavy-duty outdoor applications, combining structural robustness with self-protective corrosion resistance. Developed under the GB/T 4171 standard, this steel features a strategic alloy composition (Cu, Cr, Ni, P) that forms a dense, adherent patina layer, eliminating the need for protective coatings in outdoor environments . With a minimum yield strength of 295 MPa and tensile strength ranging from 430–560 MPa, it delivers exceptional load-bearing capacity for bridges, cranes, and industrial machinery .
Material Properties for Heavy-Duty Performance
Structural Integrity & Dynamic Load Capacity
Q295NH steel's mechanical properties are optimized for heavy-duty applications. Its 295 MPa yield strength ensures stability under extreme loads, while an elongation rate of ≥22% provides ductility to absorb dynamic stresses in wind-exposed bridges or high-cycle crane operations . Optional impact resistance testing (≥27 J at -20°C) guarantees performance in subzero climates, critical for infrastructure in cold regions .
Self-Healing Corrosion Protection
The alloy's Cu, Cr, and Ni content promotes the formation of a stable, non-porous patina layer that acts as a natural barrier against moisture, UV radiation, and industrial pollutants. This mechanism provides 8 times higher corrosion resistance than carbon steel in outdoor environments, reducing maintenance costs by 30–50% over painted steel . For coastal or industrial applications, the patina layer prevents chloride-induced corrosion and surface degradation, extending service life by 20–30% compared to conventional materials .
FAQ
1. What is the minimum yield strength of Q295NH Weather Resistant Steel?
Answer: The minimum yield strength is 295 MPa.
2. Which alloy elements form the protective patina layer in Q295NH?
Answer: Copper (Cu), chromium (Cr), nickel (Ni), and phosphorus (P) promote the patina.
3. How does Q295NH's corrosion resistance compare to carbon steel?
Answer: It offers 8 times higher corrosion resistance than carbon steel, reducing maintenance costs by 30–50%.
4. What are the key applications of Q295NH in heavy-duty projects?
Answer: Bridges, cranes, industrial machinery, and infrastructure in cold or coastal regions.
5. What mechanical properties make Q295NH suitable for dynamic loads?
Answer: An elongation rate of ≥22% for ductility and optional impact resistance (≥27 J at -20°C) for cold climates.
