ISSN:
1662-9779
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Physics
Notes:
In the API X65 steel, effects of rolling and cooling conditions on microstructure andmechanical properties were studied. In the case of accelerated cooling after multi-pass rolling in thehigh/low unrecrystallized range, the tensile strength was 574-670 MPa and the impact toughness was74-109 J. In the case of accelerated cooled to 550℃ and then interrupted by air cooling, on the otherhand, those values were 524-538 MPa and 100-135 J, respectively. Whereas the former exhibited thecontinuous yielding, the latter showed discontinuous yielding. In addition, yield ratio increased from0.59-0.67 to 0.85-0.87, accompanied with the enhancement of yield strength. Ultrafine ferrite grainsformed by the strain induced dynamic transformation during the severe rolling and second phasesformed during cooling were observed. In accelerated cooling and interrupted cooling conditions, mainsecond phases formed after cooling were martensite and pearlite, respectively. Separation crackingmostly observed at interfaces of ferrite matrix and second phases, may be attributed to the intrinsicinterfacial weakness
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/23/transtech_doi~10.4028%252Fwww.scientific.net%252FSSP.124-126.1341.pdf
