【摘要】 利用热模拟实验机Gleeble 3800结合锻造实验、显微组织观察、电子探针成分分析等方法研究了加热温度、变形温度、变形量、冷却速率对齿轮钢SAE8620H连铸坯表层区域和内部区域试样的带状组织的影响,结果表明,元素偏聚小的表层区域无带状组织形成,元素偏析明显的内层区域在适宜的条件下形成不同程度的带状组织,锰等元素的偏析是带状组织形成的必要条件,可以通过提高加热温度、增大变形量等方式减轻或降低带状组织。更多还原

【Abstract】 Effects of heating temperature,deformation temperature,deformation amount and cooling velocity on formation of banded structure of gear steel SAE8620 H samples from surface layer zone and inner zone of the billet were studied on a Gleeble 3800 thermal simulator combined with forging experiment,optical microscope observation and element analysis by electrone microprobe analyzer. The results show that no banded structure forms in the surface layer zone samples with less element segregation,while for the inner zone samples with obvious element segregation,different banded structure is observed. It is concluded that the segregation of Mn,Si and Mo elements is responsible for the formation of the banded structure,but levels of the banded structure can be decreased by increasing the heating temperature and deformation amount.更多还原