Aging Precipitation Evolving Process and its Effects on Mechanical Properties of 0Cr21Ni6Mn9N Austenitic Stainless Steel

2015 ◽  
Vol 816 ◽  
pp. 255-261
Author(s):  
Na Yun Jiang ◽  
Fu Shun Liu

The solution treatment (ST) and the the second phase morphology changing duing the aging precipitation process of 0Cr21Ni6Mn9N austenitic stainless steel were investigated using optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM) with EDS and transmission electron microscope (TEM). The results showed that the precipitation phase was Cr2N which initially nucleated along austenitic grain boundaries and then grew towards into the inner grains in strip morphology. Also, with the longer aging time the proportion of Cr2N increased. The mechanical properties of alloys with and without the presence of the precipitation Cr2N were also studied. It was observed that due to the exiting of the precipitation Cr2N, the strength of 2169N stainless steel reduced during a certain range of aging time, and then improved when the aging time reached to 48h, while the elongation decreased thoroughly.

2021 ◽  
Vol 118 (6) ◽  
pp. 601
Author(s):  
Chunhui Jin ◽  
Honglin Zhou ◽  
Yuan Lai ◽  
Bei Li ◽  
Kewei Zhang ◽  
...  

The influence of aging temperature on microstructure and mechanical properties of Cr15Ni5 precipitation hardening stainless steel (15-5 PH stainless steel) were investigated at aging temperature range of 440–610 °C. The tensile properties at ambient temperature of the 15-5 PH stainless steel processed by different aging temperatures were tested, and the microstructural features were further analyzed utilizing optical microscope (OM), transmission electron microscope (TEM), electron backscatter diffraction (EBSD) as well as X-ray diffraction (XRD), respectively. Results indicated the strength of the 15-5 PH stainless steel was firstly decreased with increment of aging temperature from 440 to 540 °C, and then increased with the increment of aging temperature from 540 to 610 °C. The strength and ductility were well matched at aging temperature 470 °C, and the yield strength, tensile strength as well as elongation were determined to be 1170 MPa, 1240 MPa and 24%, respectively. The microstructures concerning to different aging temperatures were overall confirmed to be lath martensite. The strengthening mechanisms induced by dislocation density and the second phase precipitation of Cu-enriched metallic compound under different aging temperatures were determined to be the predominant strengthening mechanisms controlling the variation trend of mechanical properties corresponding to different aging temperatures with respect to 15-5 PH stainless steel.


2010 ◽  
Vol 654-656 ◽  
pp. 66-69 ◽  
Author(s):  
Chuang Li ◽  
Xue Min Wang ◽  
Xin Lai He ◽  
Cheng Jia Shang ◽  
Yu He

The properties and precipitation behavior of Cu-bearing steels have been investigated. The optical microscope and transition electron microscope were employed to study the influence of interrupted cooling and quenching temperature on the precipitation behavior. Also, the properties of samples with different quench processes were tested. The results show that when the steel is interruptedly cooled and quenched from 650-700°C, with the quenching temperature increasing the volume fraction of martensite becomes larger and the hardness becomes higher. When the microstructure is ferrite the second-phase precipitates occurs and they are proved copper-rich particles. However there are no obvious precipitates in martensite. The copper-rich second phase forms by the way of inter-phase precipitation.


2011 ◽  
Vol 383-390 ◽  
pp. 3976-3979
Author(s):  
Ming Wen ◽  
Wei Li ◽  
Xiao Ming Cao

The stainless steel is more and more applications to the medical field; the most is the austenitic stainless steel. In this paper, 00Cr18Ni14Mo3 mechanical properties of austenitic stainless steel screw, compared to the solution of the former and the sample microstructure after solution treatment, energy spectrum and the torque angle reverse faults, compared to solution treatment found that mechanical properties of the samples after meet the standard can be applied to practice.


Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3299
Author(s):  
Keda Jiang ◽  
Yanquan Lan ◽  
Qinglin Pan ◽  
Yunlai Deng

The effect of the Zn/Mg ratio on microstructures, mechanical properties and corrosion performances of Al-Zn-Mg alloys was studied. Microstructures were characterized using the optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). Tensile tests, intergranular corrosion (IGC) and stress corrosion cracking (SCC) tests were conducted to study the properties. Microstructures results indicated that with the decrease of the Zn/Mg ratio, the recrystallization proportion and the fraction of second phase decreased, while the size of η’ (MgZn2) phases in grain interior also significantly decreased. The number density of η’ phases in grain interior increased and grain boundary precipitates developed discontinuous distribution with the decrease of the Zn/Mg ratio. These microstructures contributed to the significant improvement of the strength and corrosion resistance. The tensile strength and yield strength increased by 34.1% and 47.4%, respectively, with the Zn/Mg ratio decreased from 11.4 to 6.1. Calculating results indicated that the enhancement of strength mainly contributed from the solid-solution strengthening, grain-boundary strengthening and precipitation strengthening. The intergranular corrosion degree was greatly relieved and the stress corrosion sensitivity index decreased from 0.031 to 0.007 with the Zn/Mg ratio decreased from 11.4 to 6.1.


2013 ◽  
Vol 711 ◽  
pp. 95-98
Author(s):  
Xiao Liu ◽  
Jing Long Liang

The effect of Ce on structure and mechanical properties of 21Cr11Ni austenitic stainless steels were studied by metallographic examination, scanning electron microscope (SEM), tensile test. The results show that the proper amount of Ce can refine microstructure of austenitic stainless steel. Fracture is changed from cleavage to ductile fracture by adding Ce to austenitic stainless steel. 21Cr11Ni stainless steel containing 0.05% Ce can improve its high temerature strength, and the strength is increased 21.81% at 1073K respectively comparing with that of 21Cr11Ni stainless steel without Ce.


2019 ◽  
Vol 969 ◽  
pp. 508-516 ◽  
Author(s):  
Rahul Singh ◽  
Surya Deo Yadav ◽  
Nikhil Malviya ◽  
Sunkulp Goel ◽  
R. Jayaganthan ◽  
...  

The present work deals with plastic deformation of 316L austenitic stainless steel (ASS) using room temperature rolling process. After solution treatment (annealing) as-received 316L ASS has been rolled for up to 90% of thickness reduction. To investigate the effect of processing on mechanical properties microstructural study, tensile and hardness tests have been conducted. The ultimate tensile strength has been improved from 767 MPa (before deformation) to 1420 MPa (after 90% deformation), and hardness value has been increased from 208 VHN (before deformation) to 449 VHN (after 90% reduction). Magnetic measurements and XRD characterization have been performed to confirm the formation of martensitic phase. Finite element analysis have also been simulated employing DEFORM-3D software to get the insight about deformation behavior. Keywords: Room temperature rolling, Finite Element Analysis, Mechanical properties, Austenitic stainless steel.


2014 ◽  
Vol 789 ◽  
pp. 308-313 ◽  
Author(s):  
Shan Ju Zhang ◽  
Mao Sheng Yang ◽  
Ting Lei

To reveal the effect of deformation ratio on high nitrogen martensitic stainless steel, the room temperature mechanical properties, microstructures and precipitates morphology were studied by using optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM) as well as mechanical tests. The results indicate that the tensile strength, yield strength and impact energy were raised 241MPa, 180MPa and 10.0J respectively, at a higher deformation ratio. While, the average original austenite grain size was refined from 14.93μm to 9.57μm when the deformation ratio was increased from 0.65 to 0.83 as well as the martensite lath width thinned from 400nm to 250nm. Furthermore, at various deformation ratios, the precipitates morphology was different in quantity, grain size and dispersion. There are more eutectic precipitates and secondary precipitates dispersed along the grain boundary as continuous chains with lower deformation ratio. On the contrary, the precipitates in specimen with higher deformation ratio were uniform and fine without chain or network. It can be inferred that the improvements on mechanical properties, microstructures and precipitates morphology are mainly due to the deformation ratio.


Sign in / Sign up

Export Citation Format

Share Document