The chemical composition of weathering steel SPA-H was optimized

Mechanical test results of hot coil production of weathering steel SPA-H before and after composition optimization. Through the composition design of low Ni and high Ti, the mechanical properties of the steel SPA-H, such as tensile strength, yield strength and elongation, are basically consistent and meet the requirements of technical standards.

The reduction of Ni content in the composition of weathering steel SPA-H will reduce the tensile strength and yield strength of steel plate, and the increase of Ti content will effectively form fine TiN inclusion, which plays the role of refining grain in the production process, improve the mechanical properties of steel plate, optimize the composition to reduce the production cost and not reduce the quality of products.

The test results of narrow part (N) and wide part crack length of the casting billet are basically consistent, both within 2mm. The test results of the casting billet crack length after the composition optimization are basically consistent, both within 2mm. The control of the casting billet crack length after the composition optimization is slightly better, and both meet the technical standards and production requirements.

Before and after composition optimization, the casting quality of weathering steel SPA-H billet, hot coil mechanical properties, end surface quality is good, after pickling surface quality is good, cold bending performance reaches 0 level, corrosion resistance and micro-morphology control, meet the technical standards and user requirements;

After composition optimization, the cost of a ton of weathering steel SPA-H is reduced by more than 80 yuan, and the annual cost reduction reaches 8 million yuan, which meets the requirements of cost reduction and efficiency improvement of weathering steel and increases the competitiveness of the product market.