冷却速度和 Nb 含量对 X80管线钢 MA 岛的影响

Effect on the island of X80 pipeline steel by cooling rate and Nb content

摘要:

以高 Nb X80管线钢为研究对象，利用金相显微镜、扫描电镜和透射电镜等实验设备对钢中 MA岛的尺寸、形貌及分布特征进行了研究和分析。研究结果表明，高 Nb X80管线钢热轧后，适当提高冷却速度可使钢中 MA 岛的形貌和分布更为细小和均匀，高的 Nb 含量促进了条状 MA 岛的生成。通过调整高 Nb X80管线钢的合金成分和热轧后的冷却速度，均可减少 MA 岛对钢性能产生的不利影响。

Abstract:

The size and morphology and distribution feature of MA (marttensite and austenite)islands in the high-Nb X80 pipeline steel were investigated and analyzed by the OM (optical microscope),SEM (scanning electron microscope)and TEM(transmission electron microscope).MA islands of the high-Nb X80 pipeline steel became more fine and uniform when cooling rate was increased after hot rolled and high-Nb content could promoted formation of the strip morphology MA island.The adverse effects on the high-Nb X80 pipeline steel properties of the MA island could be reduced when the composition and cooling rate were adjusted.