基于低C-Si—Mn加0．10％Nb而不加Mo的合金化设计，用高温轧制工艺（HTP，high temperature processing）在实验室制得APIX80级别管线钢．本次试验确定的主要技术参数为：精轧终轧温度830--850℃，终冷温度500--550℃，冷速25--28℃／s...基于低C-Si—Mn加0．10％Nb而不加Mo的合金化设计，用高温轧制工艺（HTP，high temperature processing）在实验室制得APIX80级别管线钢．本次试验确定的主要技术参数为：精轧终轧温度830--850℃，终冷温度500--550℃，冷速25--28℃／s，精轧总压下率不小于75％．得到的组织以针状铁素体为主，加少量块状铁素体和粒状贝氏体，并在晶界分布有岛状组织．对冲击断口的金相、SEM（scanning electron microscopy）和EDS（energy dispersion scanner）观察发现脆性第二相粒子和原始奥氏体晶界是该管线钢的主要裂纹源．因此，有效控制管线钢中脆性第二相粒子，同时避免出现原始奥氏体晶界可以有效提高韧性．展开更多
Based on the daily maximum temperature data covering the period 1961-2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days（HTDs）and the mean daily maximum tem...Based on the daily maximum temperature data covering the period 1961-2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days（HTDs）and the mean daily maximum temperature（MDMT）during annual and monthly HTDs in East China were studied.The results show that the mean annual HTDs were 15.1 and the MDMT during annual HTDs was 36.3℃in the past 45 years.Both the mean annual HTDs and the MDMT during annual HTDs were negative anomaly in the1980s and positive anomaly in the other periods of time,oscillating with a cycle of about 12-15 years.The mean annual HTDs were more in the southern part,but less in the northern part of East China.The MDMT during annual HTDs was higher in Zhejiang,Anhui and Jiangxi provinces in the central and western parts of East China.The high temperature process（HTP） was more in the southwestern part,but less in northeastern part of East China.Both the HTDs and the numbers of HTP were at most in July,and the MDMT during monthly HTDs was also the highest in July.In the first 5 years of the 21st century,the mean annual HTDs and the MDMT during annual HTDs increased at most of the stations,both the mean monthly HTDs and the MDMT during monthly HTDs were positive anomalies from April to October,the number of each type of HTP generally was at most and the MDMT in each type of HTP was also the highest.展开更多
文摘基于低C-Si—Mn加0．10％Nb而不加Mo的合金化设计，用高温轧制工艺（HTP，high temperature processing）在实验室制得APIX80级别管线钢．本次试验确定的主要技术参数为：精轧终轧温度830--850℃，终冷温度500--550℃，冷速25--28℃／s，精轧总压下率不小于75％．得到的组织以针状铁素体为主，加少量块状铁素体和粒状贝氏体，并在晶界分布有岛状组织．对冲击断口的金相、SEM（scanning electron microscopy）和EDS（energy dispersion scanner）观察发现脆性第二相粒子和原始奥氏体晶界是该管线钢的主要裂纹源．因此，有效控制管线钢中脆性第二相粒子，同时避免出现原始奥氏体晶界可以有效提高韧性．
基金Funded by R&D Special Fund for Public Welfare Industry(meteorology),No.GYHY(QX)2007-6-19Na-tional Scientific and Technical Supporting Programs,No.2006BAK13B05
文摘Based on the daily maximum temperature data covering the period 1961-2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days（HTDs）and the mean daily maximum temperature（MDMT）during annual and monthly HTDs in East China were studied.The results show that the mean annual HTDs were 15.1 and the MDMT during annual HTDs was 36.3℃in the past 45 years.Both the mean annual HTDs and the MDMT during annual HTDs were negative anomaly in the1980s and positive anomaly in the other periods of time,oscillating with a cycle of about 12-15 years.The mean annual HTDs were more in the southern part,but less in the northern part of East China.The MDMT during annual HTDs was higher in Zhejiang,Anhui and Jiangxi provinces in the central and western parts of East China.The high temperature process（HTP） was more in the southwestern part,but less in northeastern part of East China.Both the HTDs and the numbers of HTP were at most in July,and the MDMT during monthly HTDs was also the highest in July.In the first 5 years of the 21st century,the mean annual HTDs and the MDMT during annual HTDs increased at most of the stations,both the mean monthly HTDs and the MDMT during monthly HTDs were positive anomalies from April to October,the number of each type of HTP generally was at most and the MDMT in each type of HTP was also the highest.
