The effect of cooling （laminar cooling） start temperature on the phase constitution was analyzed by quanti- tative metallography. The martensite/austenite （M/A） island distribution was fixed by colour metallograph...The effect of cooling （laminar cooling） start temperature on the phase constitution was analyzed by quanti- tative metallography. The martensite/austenite （M/A） island distribution was fixed by colour metallography. The strength and uniform elongation of the steels were tested with quasi-static tensile testing machine. The in-coordinate deformation of the soft and hard phases was analyzed using FEM. The results indicate that when the cooling start temperature is 690 ℃, the mechanical properties are the best, meeting the requirements of X80 high deformability pipeline steel.展开更多
Static and dynamic continuous cooling transformations （CCT） of 610 MPa HSLA steel plate for 150000 m^3 oil storage tank construction were measured by using an MMS200 thermomechanical simulation system. It was found ...Static and dynamic continuous cooling transformations （CCT） of 610 MPa HSLA steel plate for 150000 m^3 oil storage tank construction were measured by using an MMS200 thermomechanical simulation system. It was found that with the increase in cooling rate, the proeutectoid ferrite, pearlite, granular bainite, and lath bainite appeared in the transformed microstructure. Compared with those of static CCT, the transformation points of acicular ferrite, granular bainite, and lath bainite in the dynamic CCT curve were shifted to the left, resulting in an increased acicular ferrite and bainite transformation area.展开更多
文摘The effect of cooling （laminar cooling） start temperature on the phase constitution was analyzed by quanti- tative metallography. The martensite/austenite （M/A） island distribution was fixed by colour metallography. The strength and uniform elongation of the steels were tested with quasi-static tensile testing machine. The in-coordinate deformation of the soft and hard phases was analyzed using FEM. The results indicate that when the cooling start temperature is 690 ℃, the mechanical properties are the best, meeting the requirements of X80 high deformability pipeline steel.
基金Item Sponsored by National Key Technology Research and Development Program of China (2007BAE51B07)
文摘Static and dynamic continuous cooling transformations （CCT） of 610 MPa HSLA steel plate for 150000 m^3 oil storage tank construction were measured by using an MMS200 thermomechanical simulation system. It was found that with the increase in cooling rate, the proeutectoid ferrite, pearlite, granular bainite, and lath bainite appeared in the transformed microstructure. Compared with those of static CCT, the transformation points of acicular ferrite, granular bainite, and lath bainite in the dynamic CCT curve were shifted to the left, resulting in an increased acicular ferrite and bainite transformation area.
