발간논문

Home > KJMM 논문 > 발간논문

Vol.37, No.3, 281 ~ 288, 1999
Title
Research Paper / Mechanical Behavior : Effects of Long - term Isothermal Aging on the Temper Embrittlement in 2.25 Cr - 1 Mo steel
공병욱Byeong Ook Kong, 김정태Jeong Tae Kim, 김동진Dong Jin Kim, 김병훈Byung Hoon Kim, 지병하Byung Ha Chi
Abstract
The present research was performed to evaluate the long-term isothermal temper embrittlement resistance and carbide behaviors. The material used in this study is SA336F22, the forged heavy wall 2.25Cr-1Mo steel. Temper embrittlement susceptibility after isothermal aging for 36,000h at 430-515℃ was assessed with the shift of the 50% fracture appearance transition temperature (FATT_(50)), 40ft-lb transition temperature (vTr_(40)) and grain boundary segregation of phosphorus by AES. XRD and TEM-EDS examined the behaviors of carbide. The shift of FATT and vTr_(40) of 2.25Cr-1Mo steel were significantly increased up to 10.000h aging then slowly saturated at 515℃. At lower temperature, however. saturation occurred slowly. The type and composition of carbides were changed to the Mo-rich stable ones(Mo-rich Mo₂C and M_6C), which reduces the Mo content in matrix. And P-segregation was detected on the prior austenite grain boundary after isothermal aging. These results suggested that the temper embrittlement be related with P-segregation caused by Mo-consuming at the matrix.
Key Words
| PDF
대한금속∙재료학회 │ (06633) 서울시 서초구 서초대로 56길 38 대한금속∙재료학회 회관 (서초1동 1666-12번지)
Tel : 070-4266-1646 │ FAX : 02-557-1080 │ E-mail : metal@kim.or.kr
Copyright ⓒ 2013 사단법인 대한금속∙재료학회 All rights reserved.