Precipitation Hardening of Triplex Steel by Using Nickel Aluminum Inter-Metallic Precipitates

2021 ◽  
Vol 318 ◽  
pp. 25-37
Author(s):  
Mahmoud M. Maghawry ◽  
Mohamed K. Elfawakhry ◽  
Hoda El Faramwy ◽  
Sabreen A. Abdelwahab ◽  
Khaled Abdel Wahed

This paper deals with three types of triplex steel, where containing 25 to 28 wt.% manganese, 0.8 to 0.89 wt.% Carbon, 9.9 to 11.11 wt.% Aluminum, and with different Nickel content. Two types contain Ni in range of 0.9 to 2 wt.% and third type doesn’t contain Ni. The precipitation of Nano-size kappa carbides is the most proper technique used for this objective. It is expected that inter-metallic strengthening mechanism should act more effective in promoting the strength of Triplex steel with ductility. From this point of view, this research was designed to study the effect of inter-metallic inductive alloying element as Nickel on promoting of the strength and ductility of the high aluminum containing high manganese steel. Optical microscope, scanning electron microscope (SEM) and X-ray diffraction (XRD) were used to detect of inter-metallic precipitates through steel investigated ranged in Nickel from 0 to 2 wt.%. Mechanical and strain hardening properties were determined in the steel investigated after different regimes of heat treatment. It was found that Ni3Al inter-metallic compound provides the austenite matrix with good strength and ductility, depending on the ageing time. Further deterioration was obviously observed in the steel investigated as increasing the ageing time, attributing to coarse structure occurrence.

2021 ◽  
Vol 318 ◽  
pp. 1-11
Author(s):  
Mahmoud M. Maghawry ◽  
Mohamed K. Elfawakhry ◽  
Hoda El Faramwy ◽  
Sabreen A. Abdelwahab

This paper presents a study of three types of Triples steel, where containing 16 to 28 wt.% manganese, 0.8 to 0.89 wt.% Carbon, 9.9 to 11.21 wt.% Aluminum, and with different Nickel content. We investigated the aging effect on properties of Triplex steel by using an optical microscope, scanning electron microscope (SEM) and X-ray diffraction (XRD). The used temperature in the ageing process is 550°C and we take three different times in that process (1min, 1hr, and 5hrs). The microstructure shows one austenite phase of an as-rolled sample without Ni and shows two austenite phases of an as-rolled sample with Ni content. The k-carbide, intermetallic phase (Ni3Al) and annealing twins formation will appear after adding Ni element. Furthermore, those phases will be increased with aging time. X-ray diffraction shows a competitive formation between the k-carbides and intermetallic phase formation during the aging time. It's confirmed that K-carbides will be formed first after that intermetallic phase, where k-carbides were formed at low temperature. Finally, we can conclude from these results that adding Ni in Triplex steel improves the ductility with 1hr aging time.


2016 ◽  
Vol 850 ◽  
pp. 659-663
Author(s):  
Xiao Gang Li ◽  
Ai Min Zhao ◽  
Hong Hong Zheng ◽  
Shao Heng Sun ◽  
Hong Xiang Yin

The microstructure and mechanical properties of a medium manganese quenching and partitioning (Q&P) steel for automobile were investigated by optical microscope (OM), scanning electron microscope (SEM), X-ray diffraction (XRD) and mechanical property test. The grain size and recovery degree were greatly affected by annealing temperature normally. The result shows that the medium manganese steel after quenching and partitioning (Q&P) heat treatment exhibited good mechanical properties. The maximum tensile strength and yield strength was 1280MPa and 1421MPa at 600°C, respectively. Additionally, the product of strength and plasticity could reached to 40472MPa×% at 640°C. Annealing temperature also had a great influence on the volume of retained austenite which increases linearly with the rise of annealing temperature as well.


2013 ◽  
Vol 431 ◽  
pp. 48-52
Author(s):  
Hong Wei Cui ◽  
Shen Bao Zhai ◽  
Shao Chun Chai ◽  
Ben Kui Gong ◽  
Lei Zhang ◽  
...  

Recently, Mg-Zn-Y alloy containing icosahedral quasicrystalline (I-phase) has attracted significant interest because it has enhanced strength and ductility at ambient temperature and at elevated temperature. However, the thermal stable I-phase with chemical composition of Mg3YZn6was formed as a coarse eutectic pocket structure in the α-Mg matrix during conventional solidification in Mg-Zn-Y alloy system. The influence of AlTiC master alloy on the morphology and amounts of I-phase in Mg-Zn-Y alloy have been investigated in this study. The microstructure and constituent phases are characterized from optical microscope (OM), X-ray diffraction (XRD) and field emission gun scanning electron microscopy (FEG-SEM). It is found that the addition of AlTiC master alloy not only can change the morphology of the I-phase, but also can increase the amount of the I-phase. The formation and growth mechanism of the I-phase have been discussed. On the other hand, the grains are also refined. It may be attributed to the combined effect of TiC and Al4C3particles, because TiC and Al4C3particles can act as heterogeneous nucleation cores of α-Mg grains. The effect of AlTiC master alloy on the ultimate tensile strength (UTS) and the elongation to failure (EL) is also discussed.


2011 ◽  
Vol 418-420 ◽  
pp. 558-562
Author(s):  
Jun Yang ◽  
Mei Ling Chen ◽  
Li Yang ◽  
Huan Jin ◽  
Hong Gao

The effects of modified SiC nano-powders on the microstructures and the work-hardening properties of shot peening treatment on high manganese steel have been carried out by means of microstructure observation, x-ray diffraction analysis and hardness testing. The results are showed that compared with the samples without modified SiC nano-powders, the microstructure of ZGMn13 are finer and markedly improved rate of work hardening. The micro-hardness of surface is enhanced significantly after the shot peening. Its strengthening mechanism is mainly twinning and dislocation, but no Martensite strengthening.


Author(s):  
J. Alias

Much research on magnesium (Mg) emphasises creating good corrosion resistance of magnesium, due to its high reactivity in most environments. In this study, powder metallurgy (PM) technique is used to produce Mg samples with a variation of aluminium (Al) composition. The effect of aluminium composition on the microstructure development, including the phase analysis was characterised by optical microscope (OM), scanning electron microscopy (SEM) and x-ray diffraction (XRD). The mechanical property of Mg sample was performed through Vickers microhardness. The results showed that the addition of aluminium in the synthesised Mg sample formed distribution of Al-rich phases of Mg17Al12, with 50 wt.% of aluminium content in the Mg sample exhibited larger fraction and distribution of Al-rich phases as compared to the 20 wt.% and 10 wt.% of aluminium content. The microhardness values were also increased at 20 wt.% and 50 wt.% of aluminium content, comparable to the standard microhardness value of the annealed Mg. A similar trend in corrosion resistance of the Mg immersed in 3.5 wt.% NaCl solution was observed. The corrosion behaviour was evaluated based on potentiodynamic polarisation behaviour. The corrosion current density, icorr, is observed to decrease with the increase of Al composition in the Mg sample, corresponding to the increase in corrosion resistance due to the formation of aluminium oxide layer on the Al-rich surface that acted as the corrosion barrier. Overall, the inclusion of aluminium in this study demonstrates the promising development of high corrosion resistant Mg alloys.


1985 ◽  
Vol 50 (10) ◽  
pp. 2139-2145
Author(s):  
Alexander Muck ◽  
Eva Šantavá ◽  
Bohumil Hájek

The infrared spectra and powder X-ray diffraction patterns of polycrystalline YPO4-YCrO4 samples are studied from the point of view of their crystal symmetry. Mixed crystals of the D4h19 symmetry are formed over the region of 0-30 mol.% YPO4 in YCrO4. The Td → D2d → D2 or C2v(GS eff) correlation is appropriate for both PO43- and CrO43- anions.


Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 570
Author(s):  
Olga Sánchez ◽  
Manuel Hernández-Vélez

ZnOTe compounds were grown by DC magnetron cosputtering from pure Tellurium (Te) and Zinc (Zn) cathodes in O2/Ar atmosphere. The applied power on the Zn target was constant equal to 100 W, while the one applied on the Te target took two values, i.e., 5 W and 10 W. Thus, two sample series were obtained in which the variable parameter was the distance from the Te targets to the substrate. Sample compositions were determined by Rutherford Backscattering Spectroscopy (RBS) experiments. Structural analysis was done using X-Ray diffraction (XRD) spectrometry and the growth of the hexagonal w-ZnO phase was identified in the XRD spectra. RBS results showed high bulk homogeneity of the samples forming ZnOTe alloys, with variable Te molar fraction (MF) ranging from 0.48–0.6% and from 1.9–3.1% for the sample series obtained at 5 W and 10 W, respectively. The results reflect great differences between the two sample series, particularly from the structural and optical point of view. These experiments point to the possibility of Te doping ZnO with the permanence of intrinsic defects, as well as the possibility of the formation of other Te solid phases when its content increases. The results and appreciable variations in the band gap transitions were detected from Photoluminescence (PL) measurements.


Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 499
Author(s):  
Klára Hosová ◽  
Jan Pinc ◽  
Andrea Školáková ◽  
Vilém Bartůněk ◽  
Petr Veřtát ◽  
...  

Zinc and its alloys seem to be promising candidates for biodegradable applications. Those materials are often modified by other elements or compounds in order to enhance their properties. The combination of zinc and apatites is challenging for several reasons. However, the advantages connected with the biological aspects suggest the need for further research into such materials. In this study, three zinc-based composites with 4 and 8 wt. % of nanohydroxyapatite or nanomonetite (Zn-4MO, Zn-4HA, Zn-8HA) were prepared by sintering and subsequent extrusion. Materials prepared in this way were characterized from the microstructural, mechanical and corrosion point of view. The obtained results showed a significant influence of particle character (amount and morphology) on the strength and ductility of the prepared materials. In case of Zn-4MO, the presence of monetite significantly increased the ductility compared with the other materials. In addition, the increment of the degradation rate caused by the presence of monetite was observed as well. All obtained results pointed out to significant advantages of monetite for the preparation of Zn-apatite composites compared with hydroxyapatite.


2011 ◽  
Vol 23 (7) ◽  
pp. 526-534 ◽  
Author(s):  
Yang Wang ◽  
Boming Zhang ◽  
Jinrui Ye

Hybrid nanocomposites were successfully prepared by the incorporation of polyethersulfone (PES) and organoclay into epoxy resin. They had higher fracture toughness than the prepared PES/epoxy blend and organoclay/epoxy nanocomposites. The microstructures of the hybrid nanocomposites were studied. They were comprised of homogeneous PES/epoxy semi-interpenetrating network (semi-IPN) matrices and organoclay micro-agglomerates made up of tactoid-like regions composed of ordered exfoliated organoclay with various orientations. The former was confirmed with dynamic mechanical analysis, scanning electron microscopy and transmission electron microscopy, while the latter was successfully observed with X-ray diffraction measurements, optical microscope, scanning electron microscope and transmission electron microscope. The improvement of their fracture toughness was due to the synergistic toughening effect of the PES and the organoclay and related to their microstructures.


2018 ◽  
Vol 25 (08) ◽  
pp. 1950025
Author(s):  
RAFIK MAIZI ◽  
ATHMANE MEDDOUR ◽  
CÉLINE ROUSSE

The deposition of Ni–Fe thin layers in boric acid and ionic liquid ([BuMePyr][Tf2N]) baths were successfully prepared. The obtained materials have been characterized by X-ray diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX) and SEM. Meanwhile, these materials were carried out by chronoamperometry or chronopotentiometry by varying the intensity of the current and the deposition potential. The results indicate that the coatings of Ni–Fe alloys were successfully obtained by electroplating on the copper substrates, and the alloys composition shows irregular behavior with polarization. The nickel content in the samples is in the range of 55–90%, but the iron content ranges from 10–30%, when potential deposits were varied from [Formula: see text]2[Formula: see text]V to [Formula: see text]4[Formula: see text]V vs Ni electrode. The results also showed that the thin layers are monophased; they contain the Ni3Fe phase. Further, SEM images of Ni–Fe alloys show the different shapes of particles.


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