Low-cost steel plate for building structure and manufacturing method thereof

Abstract

The invention discloses a low-cost steel plate for a building structure and a manufacturing method thereof. The steel plate comprises the following chemical components: C accounts for 0.14 percent to 0.17 percent, Si accounts for 0.20 percent to 0.50 percent, Mn accounts for 1.30 percent to 1.50 percent, P is equal to or less than 0.012 percent, S is equal to or less than 0.005 percent, Alt accounts for 0.020 percent to 0.060 percent, and the balances are Fe and unavoidable foreign impurities. (1) No noble metal elements such as Nb, V, Ti, Ni, Cr, Mo and the like, are added in the steel, the requirement of Q345GJ strength level is met completely though the chemical components C-Si-Mn-Al, and the cost is low; (2) the steel is purer, P is equal to or less than 0.012 percent, and S is equal to or less than 0.005 percent; (3) the impact toughness is good at the temperature of minus 40 DEG C, and the Charpy impact energy of a V-shaped notch is equal to or higher than 80 J; (4) the earthquake resistance is good, and the actual yield ratio is respectively smaller than 0.78; and (5) the lamellar tearing resistance is excellent, and the actual Z-direction section shrinkage ratio in the total-thickness direction is equal to or higher than 38 percent. The hot-rolling Q345GJEZ35 steel plate used for the building structure and provided with thickness of 20-90 mm can be produced, and the steel plate and the manufacturing method can be applied to the manufacture of the steel structure of the high-rise building, have good comprehensive performance and simple production process, can realize the batch production and have low cost.

Description

technical field [0001] The invention relates to a steel plate for low-cost building structure, which is applied to the steel structure of high-rise buildings, and also relates to a production method of the steel plate for low-cost building structure. Background technique [0002] At present, steel for building structures has been used in the domestic construction field, but the steel products with the same strength level or greater than that of the present invention are all based on the basic chemical composition of C-Si-Mn-Al, and Nb, V, Ti, Ni, One or more of Cr, Mo and other elements. [0003] The Chinese invention patent with the patent number 200810104298.5 discloses a steel plate for high-rise buildings. The steel is characterized in that the chemical composition is C: 0.12-0.17%, Si: 0.30-0.45%, and Mn: 1.35-1.55%. , P: ≤0.022%, S: ≤0.010%, Alt: 0.020-0.050%, V: 0.03-0.10%. The steel is added with V alloy elements, and the cost is high; the content of S and P is hig...

AI Technical Summary

Problems solved by technology

The steel is added with V alloy elements, and the cost is high; the content of S and P is high, and the maximum thickness of the steel plate is only 60mm

[0004] The Chinese invention patent with the patent number 01133562.9 discloses a high-performance fire-resistant and weather-resistant construction steel and its production method. The steel contains Mo, Ni, Cr, Cu, Ti, Nb, V and other alloying elements, and the alloy cost is high ; The steel adopts normalizing + tempering process after rolling, and the production process cost is high