Abstract: Effect of cooling rate after rolling (20 ~0. 5 °C /s) , initial pass temperature of finishing rolling ( 1 000 ~ 900 °C ) , last pass temperature of finishing rolling (860 ~750 °C ) and coiling temperature (630 ~ 500 °C  ) on niicrostnie- ture of pipeline steel X65 (0. 08% C, 1. 38% Mn, 0. 032% Nb, 0. 041 % V, 50 x 10^-6 N ) has been studied by using Gleeble-3500 thermal-mechanical simulator. Results showed that with increasing cooling rate after rolling, decreasing reduction ratio at about 950  °C , decreasing finishing and coiling temperature, the microstructure of plate products was finer. The rolling temperature for 7. 1 mm finished plate rolled by 150 mm x 1 700 mm slab was proposed that 1 150 ~ 1 200 °C heating, rough rolling ≤1 130 °C to 35 mm, initial pass finishing rolling 950 ~ 1 020 °C , last pass finishing rolling ≤83O °C , and coiling ≤580 °C , and the mechanical properties of products met the requirement of standard.

Key words: Pipeline Steel X65, Controlling Rolling and Cooling, Process Parameters, Microstructure

摘要： 应用Gleeble-3500热/力模拟试验机研究了轧后冷速(20～0.5℃/s)、卷取温度(630～500℃)、精轧初始温度(1 000～900℃)、末道次精轧温度(860～750℃)对X65管线钢(0.08%C、1.38%Mn、0.032%Nb、0.041%V、50×10-6N)显微组织的影响。结果表明,增加轧后冷却速度、减小950℃左右的压下量,降低终轧和卷取温度可细化板材组织。提出150 mm×1 700 mm板坯轧成7.1 mm成品板的轧制温度为:1 150～1 200℃加热,≤1 130℃粗轧至35 mm,950～1 020℃精轧,≤830℃终轧,≤580℃卷取,其产品力学性能满足标准要求。

关键词: X65管线钢, 控轧控冷, 工艺参数, 组织