scholarly journals Effects of the Nanostructured Fe-V-Nb Modificators on the Microstructure and Mechanical Properties of Si-Mn Steel

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Tiebao Wang ◽  
Chunxiang Cui ◽  
Kuo Jia ◽  
Lichen Zhao

The nanostructured Fe-V-Nb master alloy was prepared in vacuum rapid quenching furnace and then was added in the steel melts as modificators before casting. Next, the effects of the nanostructured Fe-V-Nb modificators on the microstructure and mechanical properties of the steel were studied. The results show that the grain size of the steel has been effectively refined, which is mainly because the dispersed nanoscale particles can produce more nucleation sites during the solidification of the liquid steel. Tensile properties and fracture morphology reveal that the yield strength and toughness of the steel modified by nanostructured Fe-V-Nb modificators are better than that of the microalloyed steel. TEM analysis shows that vanadium and niobium in the modificators exist in the form of (V, Nb) C which effectively increases the nucleation rate and leads to better mechanical properties of the steel.

2011 ◽  
Vol 399-401 ◽  
pp. 228-232
Author(s):  
An Ming Li ◽  
Meng Juan Hu

Microstructure and mechanical properties of 60Si2Mn steel by 870 °C prequenched and second sub-temperature quenching was studied. The results showed that the hardness of the 60Si2Mn steel first increased and then decreased with increasing second sub-temperature quenching temperature, and the highest hardness was obtained when sub-temperature quenching temperature was 800 °C.The sample after second sub-temperature quenching was composed of martensite and a little ferrite phase. The abundance of ferrite phase decreased with the increase in second sub-temperature quenching temperature. Fine martensite was obtained by second sub-temperature quenching, which may be relate to the grain refinement of austenitic phase and austenitic nucleation sites. The mechanical properties of the 60Si2Mn steel after 870 °C prequenching and second sub-temperature quenching are better than that of conventional samples after 870 °C quenching.


2013 ◽  
Vol 589-590 ◽  
pp. 572-577 ◽  
Author(s):  
Hua He Liu ◽  
Han Lian Liu ◽  
Chuan Zhen Huang ◽  
Bin Zou ◽  
Ya Cong Chai

Al2O3-MgO, Al2O3-Y2O3 and Al2O3-MgO-Y2O3 composite ceramics were fabricated respectively by hot-press sintering technique. With the analysis of the mechanical properties and microstructure, it was found that single additive MgO could be more favorable to the grains’ refinement and densification than Y2O3; the composite additive including both MgO and Y2O3 was better than single additive MgO or Y2O3, because their interactions could improve the mechanical properties of the Al2O3 ceramics; The sintering temperature could be reduced by adding the suitable amount of composite additives.


2021 ◽  
Vol 825 ◽  
pp. 141926
Author(s):  
Chao Wang ◽  
Liming Yu ◽  
Ran Ding ◽  
Yongchang Liu ◽  
Huijun Li ◽  
...  

2013 ◽  
Vol 750-752 ◽  
pp. 119-122 ◽  
Author(s):  
Xiao Ya Wang ◽  
Zhi Dong Xia ◽  
Zhe Li

This study was carried out to discuss the influence of curing temperature on the performance of conductive composites filled with nickel-coated graphite (NCG). The electrical conductivity, crosslink density, mechanical properties and tensile fracture morphology have been investigated. The results indicated that curing temperature had great impact on the electrical conductivity and mechanical properties. Voluem resistivity decreased from 43.1 to 0.08 ohm-cm at 125°C-205°C, and the reason was discussed in light of formation and break of the conductive network in the composites. The stability of SR-NCG cured at 165°C-205°C were also better than those cured at other curing temperature. Besides, tensile strength increased from 2.41 to 7.19Mpa at 125°C-225°C, elongation at break have a 56% increase, and Shore A hardness also incresed from 74 to 82.


Sign in / Sign up

Export Citation Format

Share Document