论文部分内容阅读
采用不同的退火工艺对X80管线钢用焊丝盘条进行了热处理,研究了退火工艺对其显微组织和力学性能的影响,得到了一种可提高焊丝加工性的退火工艺。结果表明:退火加热温度过低或冷却速度过大,应力消除不好,不能降低盘条的拉伸性能与硬度,提高盘条的塑性。退火温度过低,粗大的碳化物含量较高,聚集在偏平、长条状的铁素体晶界;冷却速度过大,晶粒大小不一致,层状分布的铁素体比例增大,珠光体含量增大。采用850℃加热,随炉冷却的退火工艺,所得组织为均匀、细小的等轴状晶粒,碳化物颗粒较细,明显降低了盘条的拉伸强度与硬度,提高了塑性,使盘条具有良好的加工性能。
Different annealing processes were used to heat treat the wire rods of X80 pipeline steel. The effects of annealing process on microstructure and mechanical properties were studied. An annealing process was proposed to improve the workability of wire. The results show that: the annealing temperature is too low or the cooling rate is too large, stress is not good, can not reduce the tensile properties and hardness of wire rod, wire rod to improve the plasticity. Annealing temperature is too low, the coarse carbide content is higher, gathered in flat, long strip of ferrite grain boundaries; cooling rate is too large, the grain size is inconsistent, layered ferrite distribution ratio increases, pearlite Increased content. The use of 850 ℃ heating, annealing furnace cooling, the resulting organization is uniform, fine equiaxed grains, carbide particles smaller, significantly reducing the wire rod tensile strength and hardness, increased plasticity, the wire rod Has a good processing performance.