The colored metallography was used to inves- tigate the morphology of martensite in Fe-Ni-C al- loys.By compression deformation martensite trans- forms from lenticular to thin-plate.It is proved that the bended and br...The colored metallography was used to inves- tigate the morphology of martensite in Fe-Ni-C al- loys.By compression deformation martensite trans- forms from lenticular to thin-plate.It is proved that the bended and broken martensites are inher- ent from compressive predeformation of austenite.展开更多
The effect of compressive deformation tested above the M_s temperature on the martensite morphology in Fe-Ni-C alloys has been studied.In the Fe-30Ni-0.12C alloy,the M_s temperature is -50℃ The cylindrical specimens ...The effect of compressive deformation tested above the M_s temperature on the martensite morphology in Fe-Ni-C alloys has been studied.In the Fe-30Ni-0.12C alloy,the M_s temperature is -50℃ The cylindrical specimens were compressively deformed at -40℃.The strain rates were 10,20,30 and 40%.X-ray analysis and metallographic examination showed that no strain-induced martensite was found.After quench- ing to -53℃,some thin plates and unusual morphologies of lenticular martensites with bent and/or broken mid-ribs were observed.In the Fe-30Ni-0.34C alloy,the M_s temperature is -120℃.Compressive deformation with different strain rates were carried out at room temperature. After quenching to the liquid nitrogen temperature, some bent thin plate matensites(unbroken)occur- red.The transformed twins in bent plate were also bent and nearly parallel to the γ-α'interfaces. Orientation relationship between austenite and bent martensite has been examined by means of trans- mission electron microscope.It was proved that these unusual morphologies are inherent in the compressive pre-deformed austenite.展开更多
文摘The colored metallography was used to inves- tigate the morphology of martensite in Fe-Ni-C al- loys.By compression deformation martensite trans- forms from lenticular to thin-plate.It is proved that the bended and broken martensites are inher- ent from compressive predeformation of austenite.
文摘The effect of compressive deformation tested above the M_s temperature on the martensite morphology in Fe-Ni-C alloys has been studied.In the Fe-30Ni-0.12C alloy,the M_s temperature is -50℃ The cylindrical specimens were compressively deformed at -40℃.The strain rates were 10,20,30 and 40%.X-ray analysis and metallographic examination showed that no strain-induced martensite was found.After quench- ing to -53℃,some thin plates and unusual morphologies of lenticular martensites with bent and/or broken mid-ribs were observed.In the Fe-30Ni-0.34C alloy,the M_s temperature is -120℃.Compressive deformation with different strain rates were carried out at room temperature. After quenching to the liquid nitrogen temperature, some bent thin plate matensites(unbroken)occur- red.The transformed twins in bent plate were also bent and nearly parallel to the γ-α'interfaces. Orientation relationship between austenite and bent martensite has been examined by means of trans- mission electron microscope.It was proved that these unusual morphologies are inherent in the compressive pre-deformed austenite.
