退火工艺对20mm厚X70管线钢热轧板卷力学性能影响研究  

Effect of Annealing Process on the Hot Rolling Coil Mechanical Properties of X70 Pipeline Steel

作　　者：朱腾威[1] 缪成亮[1] 程政[2] 陈一[2] 杨孝鹤[2] 李飞[1] 

机构地区：[1]首钢技术研究院 [2]首钢京唐钢铁联合有限责任公司

出　　处：《首钢科技》2016年第5期15-19,46,共6页Shougang Science and Technology

摘　　要：对不同退火工艺下20mm厚X70管线钢热轧板卷的力学性能进行了研究，并采用光学显微镜和场发射扫描电镜对不同退火工艺下X70管线钢热轧板卷的显微组织进行了分析。结果表明，随退火温度升高，屈服强度和抗拉强度均呈现先增大、后减小的趋势，退火温度在550℃以上时屈强比上升。在550℃以上温度保温导致晶粒尺寸增大，且伴随渗碳体大量析出，割裂基体，从而导致-10℃落锤性能恶化。退火温度在500℃及以下时对组织性能影响不大。The influence of hot-rolled coil mechanical properties of X70 pipeline steel under different annealing processes was studied and the corresponding microstructure was investigated by the Optical Microscope and Field Emission Scanning Electron Microscopy. The results showed that both yield strength and tensile strength presented a trend from rise to decline with the increase of annealing temperature. When the annealing temperature was beyond 550 ℃, the yield ratio has been increasing. The grain sizes were coarse due to holding temperature above 550 ℃. Furthermore, a large amount of cementite precipitated, which induced matrix fragmentation and woresen the - 10 ℃ DWTF Toughness. The annealing temperature had little effect on the microstructure and mechanical properties when it was below 500 ℃.

关 键 词：厚规格管线钢 退火 韧性 落锤 

分 类 号：TG146.21[一般工业技术—材料科学与工程]