Effect of Cold Working and Aging Treatment on the Mechanical Properties of Co-Ni Alloy

2017 ◽  
Vol 898 ◽  
pp. 461-466
Author(s):  
Cheng Zhuang Lu ◽  
Jing Yuan Li ◽  
Dong Yan Yang ◽  
Yu Lai Chen
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Cold Working ◽  
Cold Deformation ◽  
Aging Treatment ◽  
High Strength ◽  
Ni Alloys ◽  
Dislocation Movement ◽  
Cold Rolled

Co-Ni alloys in which Co, Ni, Cr and Mo are principal elements, exhibit an impressive combination of high strength, high toughness, and excellent corrosion resistance. In this study, the effects of cold-rolled combined with the heat-treatment ranged from 673 to 973 K from 1hour to 10 hours on the mechanical properties and microstructures of Co-Ni alloys were investigated systematically. The relations between the aging temperature and mechanical properties were concluded. The initial ultimate tensile strength of 790 MPa increased to 1808 MPa by cold rolled 80 pct. After aging the cold-rolled alloy (80 pct ) at temperature 773K for 4hours, the ultimate tensile strength and the hardness reached to 2220MPa and 759(HV), respectively. It is found that the material was hardened by the cold working and aging which provided the second hardening. However, TEM observations and X-ray diffractions suggested that no structural change could be found. The cold deformation introduced platelets of a few atomic layers in thickness less than 100 nm, which were identified as stacking faults. A high density of nanoplatelets and dislocations, piled up in the vicinity of twin plate strengthened materials. The aging treatment provided the second major source of strengthening after cold-working (and only after cold-working) by the formation of secondary twins. The ultimate strength resulted from that the intersection of deformation twins and secondary twins blocking the dislocation movement.

scholarly journals Achievement of High Strength and Ductility in Al–Si–Cu–Mg Alloys by Intermediate Phase Optimization in As-Cast and Heat Treatment Conditions

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 647 ◽  
Author(s):  
Bingrong Zhang ◽  
Lingkun Zhang ◽  
Zhiming Wang ◽  
Anjiang Gao
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Intermediate Phase ◽  
High Strength ◽  
Mg Alloys ◽  
Artificial Ageing ◽  
Treatment Conditions ◽  
Eutectic Si

In order to obtain high-strength and high-ductility Al–Si–Cu–Mg alloys, the present research is focused on optimizing the composition of soluble phases, the structure and morphology of insoluble phases, and artificial ageing processes. The results show that the best matches, 0.4 wt% Mg and 1.2 wt% Cu in the Al–9Si alloy, avoided the toxic effect of the blocky Al2Cu on the mechanical properties of the alloy. The addition of 0.6 wt% Zn modified the morphology of eutectic Si from coarse particles to fine fibrous particles and the texture of Fe-rich phases from acicular β-Fe to blocky π-Fe in the Al–9Si–1.2Cu–0.4Mg-based alloy. With the optimization of the heat treatment parameters, the spherical eutectic Si and the fully fused β-Fe dramatically improved the ultimate tensile strength and elongation to fracture. Compared with the Al–9Si–1.2Cu–0.4Mg-based alloy, the 0.6 wt% Zn modified alloy not only increased the ultimate tensile strength and elongation to fracture of peak ageing but also reduced the time of peak ageing. The following improved combination of higher tensile strength and higher elongation was achieved for 0.6 wt% Zn modified alloy by double-stage ageing: 100 °C × 3 h + 180 °C × 7 h, with mechanical properties of ultimate tensile strength (UTS) of ~371 MPa, yield strength (YS) of ~291 MPa, and elongation to fracture (E%) of ~5.6%.

Effect of Zr on the microstructures and mechanical properties of as-extruded Mg–2.3Zn–0.18Y–xZr alloys

2017 ◽  
Vol 31 (16-19) ◽  
pp. 1744001 ◽  
Author(s):  
Yufan Wang ◽  
Yingbo Zhang ◽  
Wei Gao
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Aging Treatment ◽  
Grain Refining ◽  
Maximum Increase ◽  
Microstructures And Mechanical Properties ◽  
Average Size ◽  
Precipitate Strengthening ◽  
Zr Alloys

The microstructures and mechanical properties of as-extruded Mg–2.3Zn–0.18Y–[Formula: see text]Zr ([Formula: see text] = 0.03, 0.06 and 0.13 at.%) alloys and aged Mg–2.3Zn–0.18Y–0.13Zr alloy were studied. The results revealed that the microstructures of as-extruded Mg–2.3Zn–0.18Y–[Formula: see text]Zr alloys are typical bimodal structures. The coarse [Formula: see text]-Mg grains are surrounded by fine dynamically recrystallized [Formula: see text]-Mg grains. The average size of [Formula: see text]-Mg grains decreases with increasing Zr content. Moreover, the addition of Zr (at.%) can improve the mechanical properties of alloy. The as-extruded Mg–2.3Zn–0.18Y–0.13Zr alloy has the best mechanical properties with ultimate tensile strength (UTS) and yield strength (YS) of 346 MPa and 292 MPa, respectively, and an elongation of 26.7%, which can be attributed to the grain refining effect and precipitate strengthening. The UTS and elongation of Mg–2.3Zn–0.18Y–0.13Zr alloy changed slightly after aging treatment, but the YS increases remarkably, with the maximum increase of 30 MPa. The fracture surfaces of all alloys consist of many tearing ridges and dimples.

scholarly journals Effect of Heat Treatment on Mechanical Properties and Microstructure Morphology of Low-Alloy High-Strength Steel

2016 ◽  
Vol 61 (2) ◽  
pp. 475-480
Author(s):  
K. Bolanowski
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Grain Size ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Yield Strength ◽  
High Strength Steel ◽  
High Strength ◽  
Strengthening Phase ◽  
Average Grain Size

Abstract The paper analyzes the influence of different heat treatment processes on the mechanical properties of low-alloy high-strength steel denoted by Polish Standard (PN) as 10MnVNb6. One of the findings is that, after aging, the mechanical properties of rolled steel are high: the yield strength may reach > 600 MPa, and the ultimate tensile strength is > 700 MPa. These properties are largely dependent on the grain size and dispersion of the strengthening phase in the ferrite matrix. Aging applied after hot rolling contributes to a considerable rise in the yield strength and ultimate tensile strength. The process of normalization causes a decrease in the average grain size and coalescence (reduction of dispersion) of the strengthening phase. When 10MnVNb6 steel was aged after normalization, there was not a complete recovery in its strength properties.

The Effect of Pre-Ageing on the Mechanical Properties of AA6061 Sheet Products

2011 ◽  
Vol 110-116 ◽  
pp. 337-342
Author(s):  
Bahman Mirzakhani ◽  
Mostafa Mansourinejad
Keyword(s):  
Mechanical Properties ◽  
Precipitation Hardening ◽  
Cold Working ◽  
High Strength ◽  
Silicon Alloys ◽  
Aging Conditions ◽  
Dislocation Pinning ◽  
Cold Rolled ◽  
Sheet Products ◽  
Dislocation Annihilation

Various designated precipitation hardening and cold working have been employed to improve mechanical properties of aluminum–magnesium–silicon alloys. The aim of this study is to study how both high strength and excellent ductility could be achieved. Two main processes are competing to each other when the cold working is combined with precipitation hardening. They are dislocation annihilation during age treatment which improves ductility; and dislocation pinning by precipitates which increases strength of materials. In this paper, the mechanical properties of cold rolled AA6061 sheets in pre-aging, single and double aging conditions were compared. The different sequences of precipitation hardening and cold working were employed to achieve both high strength and excellent ductility. The results show that the amount of initial cold rolling and pre-aging may have negligible effect on the strength and hardness but significant effect on the ductility of alloy.

Recrystallization Annealing of Cold Rolled 9Cr 1Mo Ferritic Steel Containing Silicon

2009 ◽  
Vol 282 ◽  
pp. 9-16
Author(s):  
M.N. Mungole ◽  
M. Surender ◽  
R. Balasubramaniam ◽  
S. Bhargava
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Yield Strength ◽  
Cold Rolling ◽  
Grain Growth ◽  
Ferritic Steel ◽  
Annealing Temperature ◽  
Recrystallization Annealing ◽  
Cold Rolled

9Cr-1Mo ferritic steel samples containing 0.2 and 0.5 wt % silicon in 40 % cold rolled state were recrystallize-annealed at 1100, 1200 and 1300 K. The grain growth and mechanical properties after recrystallization-annealing for 20 hr to 100 hr were investigated. No significant grain growth was observed even after 100 hr annealing at 1100 and 1200 K. The recrystallization-annealing at 1200 K resulted grains smaller in size than those at 1100 K. Annealing at 1300 K exhibited the enhanced grain growth with decorative microstructures. Initial annealing after cold rolling at 1100 K exhibited low hardness which further increased with annealing temperature. Annealing at 1100 K for 20 hrs exhibited low yield strength and ultimate tensile strength compared to those of as received samples. However, for 100 hrs annealing these properties remained nearly constant for 0.2 Si composition and increased marginally for 0.5 Si composition. Recrystallization-annealing exhibited improved ductility for both the compositions.

Prediction of the Ultimate Tensile Strength in API X70 Line Pipe Steel Using an Artificial Neural Network Model

2019 ◽  
Vol 297 ◽  
pp. 71-81
Author(s):  
Adel Saoudi ◽  
Djahida Lerari ◽  
Farida Khamouli ◽  
L'Hadi Atoui ◽  
Khaldoun Bachari
Keyword(s):  
Neural Network ◽  
Mechanical Properties ◽  
Artificial Neural Network ◽  
Tensile Strength ◽  
Chemical Composition ◽  
Ultimate Tensile Strength ◽  
Yield Strength ◽  
High Strength ◽  
Ann Model ◽  
Mean Relative Error

An artificial neural network (ANN) model has been developed for the analysis and simulation of the correlation between the chemical composition and mechanical properties of high strength low alloy (HSLA) steel X70. The input parameters of the model consist of the base metal chemical composition (C, Si, Mn, the sum of Cr+Cu+Ni+Mo, the sum of Nb+Ti+V, carbon equivalent CEpcm) and the yield strength (YS). The outputs of the ANN model include the ultimate tensile strength (UTS) of the test material. Scatter plots, correlation coefficient (R) and mean relative error (MRE) were used to assess the performance of the developed neural network. Interestingly, the model output is efficient to calculate the mechanical properties of high strength low alloy steels, especially the ultimate tensile strength as a function of chemical composition and yield strength of the used material. The obtained results are in a good agreement with experimental ones, with high correlation coefficient and low mean relative error. The predictions accuracy of the developed model also conforms to the results of mean paired T-test.

Effects of Deformation Strains and Annealing Temperatures on Mechanical Properties of Martensitic Steels

2010 ◽  
Vol 654-656 ◽  
pp. 218-221 ◽  
Author(s):  
Jong Chul Lee ◽  
Ui Gu Kang ◽  
Chang Suk Oh ◽  
Sung Joon Kim ◽  
Won Jong Nam
Keyword(s):  
Mechanical Properties ◽  
Annealing Temperature ◽  
Cold Deformation ◽  
High Strength ◽  
Total Elongation ◽  
Good Combination ◽  
Martensitic Steels ◽  
Annealing Temperatures ◽  
Cold Rolled ◽  
Carbide Particles

The effects of deformation strains and annealing temperatures on microstructures and mechanical properties of martensitic steels were examined. The amount of cold deformation was changed as 30%, 50% and 60%, and annealing temperatures varied from 500°C to 600°C. In samples cold rolled 30%, the dominant microstructure for an annealing at 500°C was dislocation substructures with uniformly distributed rod-shaped carbide particles. For an annealing at 600°C, the microstructure consisted of equiaxed ultrafine grains, spherical carbide particles and elongated dislocation substructures. A proper annealing temperature for martensitic steels received 30% reduction, showing a good combination of a high strength, 1230MPa, and an adequate total elongation. 9.4%, was found as 500°C.

scholarly journals Microstructure and Mechanical Properties of Structural Steel after Dynamic Cold Working Deformation/ Wpływ Dynamicznego Odkształcenia Plastycznego Na Zimno Na Mikrostrukturę I Własności Stali Konstrukcyjnej

2014 ◽  
Vol 59 (4) ◽  
pp. 1699-1703 ◽  
Author(s):  
J. Pacyna ◽  
R. Dabrowski ◽  
E. Rozniata ◽  
A. Kokosza ◽  
R. Dziurka
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Impact Strength ◽  
Yield Stress ◽  
Cold Working ◽  
Strong Relationship ◽  
The Common ◽  
Reduction Of Area ◽  
Grade Steel

Abstract The results of the selected mechanical properties i.e. ultimate tensile strength (UTS), yield stress (YS), elongation (EL), reduction of area (RA), hardness (HV) and impact strength (KCV) of the common, S235JR grade steel, are presented in the paper. A strong relationship between the above mentioned properties and cooling rates after hot rolling of rods, made of this steel, was found. Additionally, the possibility of further enhancing of mechanical properties (UTS and YS) by the controlled, dynamic cold working, was shown. The use of such deformation, through changes in the microstructure allows for the upper yield stress (YS) increase - app. 10% and ultimate tensile strength UTS - app. 5%. Simultaneously, very high indicators of plasticity (EL, RA) and impact strength (KCV) are retained, as they were immediately after the rolling. The possibility of improving the mechanical properties of rods made of this steel grade has a great technological and commercial importance for its manufacturers, as well as for their final users.

Study of Microstructure and Mechanical Properties of Hot-Rolled Ultra-High Strength Ferrite-Bainite Dual Phase Steel

2018 ◽  
Vol 921 ◽  
pp. 208-213 ◽  
Author(s):  
Zhuang Li ◽  
Wei Lv
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Dual Phase Steel ◽  
High Strength ◽  
Dual Phase ◽  
Finish Rolling ◽  
Fast Cooling ◽  
Hot Rolled ◽  
Low Temperature Rolling

Effects of thermo-mechanical control processing (TMCP) on microstructure and mechanical properties of hot-rolled ultra-high strength ferrite-bainite dual phase steel were investigated on a laboratory hot rolling mill. The results have shown that the microstructure containing ferrite and bainite can be obtained by TMCP. Ultimate tensile strength of all the specimens exceeded 1000MPa. Finish rolling temperatures affect the mechanical properties of ultra-high strength ferrite-bainite dual phase steel. Ultimate tensile strength reached 1078MPa at relatively low finish rolling temperature because of the ferrite grains refined. Fast cooling after low temperature rolling results in the ferrite grains refined and the formation of martensite islands. As a result, the product of ultimate tensile strength and total elongation (Rm×A50) of specimen 4 with fast cooling after low temperature rolling reaches the maximum value (18096MPa%).

Effect of ECAP Prior to Aging on Microstructure, Precipitation Behaviour and Mechanical Properties of an Al-Cu-Mg Alloy

2018 ◽  
Vol 385 ◽  
pp. 290-295 ◽  
Author(s):  
Ivan Zuiko ◽  
Marat Gazizov ◽  
Rustam Kaibyshev
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Microstructure Evolution ◽  
Thermomechanical Processing ◽  
High Strength ◽  
Mg Alloy ◽  
Angular Pressing ◽  
Precipitation Behaviour ◽  
Peak Aged

Microstructure, precipitation behaviour and mechanical properties of an Al-5.64Cu-0.33Mn-0.23Mg-0.14Zr-0.11Ti (in wt. %) alloy subjected to thermomechanical processing (TMP) involving equal-channel angular pressing (ECAP) at ambient temperature to total strains (ε) of ~1 and ~2 followed by aging at 180°C for 0-28 h have been investigated and compared with conventional aging at the same temperature (T6 state). TMP led to significant increase in yield stress (YS) and ultimate tensile strength (UTS) and decrease in elongation-to-fracture as compared to the peak-aged T6 state. The YS, UTS and δ values attained after ECAP to ε ~ 2 followed by peak ageing were ~510 MPa, ~540 MPa and ~7.6%, respectively. The changes in mechanical properties were related to microstructure evolution and precipitation behaviour. TMP conditions obtaining a high-strength state of the Al-Cu-Mg alloy are discussed.

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