Study on Fe-5Cr-4.5Ni-2Mo-0.5Ti-0.3Al-0.2C Alloy

• Main Authors: Chun-Kuo Wang, 王駿幗
• Other Authors: Chih-Yeh Chao
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/30951219489296261030

碩士 === 國立屏東科技大學 === 機械工程系所 === 97 === The purposes of the studies are to investigate the phase transformations, mechanical properties and microstructures of Fe-5Cr-4.5Ni-2Mo-0.5Ti-0.3Al-0.2C alloy by use of X-ray diffraction (XRD), optical microscope (OM) and transmission electron microscope (TEM). Some results are described as following: Being SHT, the ultimate tensile strength, yielding strength and elongation of the alloy are in the range of 965-1380 MPa, 930-1260 MPa, 6.5-3.8 %, respectively. After aged at 450-650 ℃ for various times, the ultimate tensile strength, yielding strength and elongation of the alloy are in the range of 1180-1690 MPa, 1040-1520 MPa, 17.0-8.2 %, respectively. Being solution heated treatment at 1100℃/1 H, the microstructure of the alloy is a plate martenite phase belonging to the B.C.C. structure. In addition, some TiC carbides were found within the matrix. When aged at 450 ℃ for various times, some α-phase precipitates had been found. And, increasing the aging temperature to 550℃, it can be observed that the L12 -type precipitates formed within the matrix. Age 650-750 ℃ for various times, the M23C6-type carbides and austenite phase formed.