特高压Q460钢管塔低温特性研究

Study on Low Temperature Characteristics of UHV Q460 Steel Tube Tower

利用扫描电镜、力学性能测试和夏比冲击等测试方法,研究了不同规格、不同质量等级的Q460钢管塔在不同温度下的力学性能、冲击韧性和断口形貌,评价了规格对不同质量等级Q460钢管的韧脆转变温度影响,研究了不同质量等级Q460钢管的低温特性。研究结果表明:Q460D钢管带状组织明显减少,其组织均匀性好于Q460C钢管。Q460D的强度(屈服强度和抗拉强度)波动范围稍窄于Q460C的范围,且不同规格的Q460D钢管的抗拉强度基本上保持一致。Q460C钢管在-40℃及以上时,其冲击功最低值在68 J以上;Q460D钢管在-60℃及以上,其冲击功最低值在163 J以上。

The mechanical properties,impact toughness and fracture morphology of Q460 steel pipes of different specifications and different quality grades at different test temperatures were studied by means of scanning electron microscopy,mechanical properties test and Charpy impact test.The influences of wall thickness on ductile-brittle transition temperature different quality grades of Q460 steel pipes were evaluated..The results show that band structure in Q460D steel tube is significantly reduced,and microstructure uniformity is better than that of Q460C steel tube.The strength variation(yield strength and tensile strength)of Q460D slightly narrows than that of Q460C,and the tensile strengths of Q460D steel pipes of different wall thickness are identical.When the Q460C steel pipe is tested at-40℃ and above,the lowest impact energy value is above 68 J,whilf the Q460D steel pipe is tested at-60℃ and above,and the lowest impact energy value is above 163 J.