非调质型15万m3石油储备罐体用610MPa高强度钢板轧制和热处理工艺研究与实践

主要采用热模拟技术研究了不同终轧工艺和不同回火温度对石油储备罐体用高强度钢板JGR610E显微组织的影响,并利用金相和萃取复型等分析方法对不同工艺下的显微结构和碳化物进行了分析。结果表明,JGR610E钢在860℃左右终轧温度、20℃/s冷却速度下可以获得板条状低碳贝氏体组织,经过620℃回火后得到具有良好强韧性能的板条贝氏体和针状铁素体混合组织,其析出相主要有两类,尺寸在300 nm左右的为含有Fe和Mn的MxCy型碳化物,尺寸范围在50～100 nm的为含有Ti和Nb的MC型碳化物,且在该回火温度下,有大量的尺寸范围在几个纳米至十几个纳米尺寸的Ti(CN)析出。

Studies on Rolling and Heat-Treatment Technologies of 610 MPa HSLA Steel Plate for 150000m3 Oil Storage Tank Construction

In this paper, microstructure and carbides of 610MPa HSLA Steel Plate for 150,000 m3 Oil Storage Tank Construction was studied under various finishing rolling temperature and heat-treatment. It has found that lathing bainite can be obtained when finishing rolling temperature is controlled at 860℃ under a cooling rate of 20℃/s and the steel is characterized as lathing bainite and acicular microstructure characterize after tempered at 620℃.There are two type of precipitates that are MxCy type of carbides and Titanium and niobium carbon-nitrides. The MxCy type of carbides are sizing 300 nano-meter, comprised of iron and manganese. MC type of Titanium and niobium carbides sizing 50 to 100 nano-meter are another important precipitates. At 620℃ tempering temperature, huge amount of titanium carbon-nitrides were found sizing in several to tens of nano-meter.