Q690qENH weathering bridge steel plate, Q690qENH steel plate fixed rolling, Q690qENH mechanical prop

Q690qENH weathering bridge steel plate, Q690qENH steel plate fixed rolling, Q690qENH mechanical prop

Q690qENH is a bridge steel plate with weather resistance, Q - the first letter of the word "yield" in Chinese pinyin of the yield strength of steel for bridges;

690 rule minimum yield strength value, unit: MPa;

Q--The first letter of the word "bridge" in Chinese pinyin of steel for bridges;

D - the quality level is D;

N--The first letter of the word "resistant" in Chinese pinyin of the weathering steel plate;

H--The word "waiting" of the weathering steel plate in Chinese Pinyin

Q690qENH implementation standard GB/T714-2015

Q690qENH steel plate fixed rolling: Wugang Xiangyang

Q690qENH Steel and contrast steel Q235 Corrosion loss and corrosion rate curves over time in a simulated industrial atmosphere.

Q690qENH and Q235 steels have higher initial corrosion rates of 0.329 and 0.453mg/cm2/h, respectively, and Q235 steels have significantly higher corrosion rates than Q690qENH steels.

The corrosion rate of the two test steels gradually decreased with the increase of time, and when the corrosion time reached 384h, the corrosion rate tended to be stable. After 784 h, the corrosion rates of Q690qENH and Q235 steel were 0.071 and 0.120 mg/cm2/h, respectively, indicating that the surface rust layer in the later stage of corrosion played a protective role in the two test steels.

The corrosion rate of Q690qENH steel was lower than that of Q235 steel throughout the test cycle.

In order to analyze the influence mechanism of alloying elements on the formation of dense rust layer, the distribution of elements in the cross-section of the rust layer after 384 h of peri-impregnated corrosion of the two test steels was analyzed by EPMA.

According to the results of elemental surface distribution, compared with Q235 steel, the Q690qENH steel rust layer showed obvious enrichment of Cu, Cr and Ni compared with Q235 steel, while the enrichment of Cu, Cr and Ni was not observed at all in Q235 steel rust layer.

There is a large amount of corrosive S enrichment in the junction between the Q235 steel rust layer and the matrix, while the S element in Q690qENH steel is mainly enriched in the outer rust layer. Si was enriched in the steel rust layer of both specimens.