Tensile Flow Behavior of 9Cr–2WVTa Reduced-Activation Ferritic/Martensitic Steel

2016 ◽  
Vol 138 (3) ◽  
Author(s):  
Hamidreza Najafi
Keyword(s):  
Tensile Strength ◽  
Martensitic Steel ◽  
Flow Behavior ◽  
True Stress ◽  
Saturation Stress ◽  
Stress Increment ◽  
True Plastic Strain ◽  
Temperature Range ◽  
Rafm Steel ◽  
Voce Equation

Tensile flow behavior of 9Cr–2WVTa ferritic/martensitic (RAFM) steel in normalized-tempered condition has been studied based on Voce equation over the temperature range of 25–600 °C. Yield strength (YS) and ultimate tensile strength (UTS) decrease with increase in temperature. However, the elongation decreases with increase in temperature up to 400 °C and then increases beyond 400 °C. True stress–true plastic strain curves at all temperatures are adequately described by the Voce equation. While saturation stress (σs) decreases with temperature, the rate at which the stress approaches the saturation value (nV) increases with temperature. The variation of the stress increment up to saturation stress (σun) with temperature shows a plateau in the temperature range of 200–400 °C. Moreover, the product of σun and nV (σun·nV) is inversely proportional to the elongation. The relation of elongation to σun·nV can be described by a power law with the exponent of −1.63.

Mechanical And Superconducting Properties Of Cu-Nb3Sn In Situ Produced Composite Wires

1981 ◽  
Vol 12 ◽  
Author(s):  
A. Kolb-Telieps ◽  
B.L. Mordike ◽  
M. Mrowiec
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Yield Strength ◽  
Wide Temperature Range ◽  
Volume Fraction ◽  
Superconducting Properties ◽  
Temperature Range ◽  
Composite Wires ◽  
Strength And Ductility

ABSTRACTCu-Nb composite wires were produced from powder, electrolytically coated with tin and annealed to convert the Nb fibres to Nb 3Sn. The content was varied between 10 wt % and 40 wt %. The superconducting properties of the wires were determined. The mechanical properties, tensile strength, yield strength and ductility were measured as a function of volume fraction and deformation over a wide temperature range. The results are compared with those for wires produced by different techniques.

Thermal Diffusivity of 16Kh12V2FTaR Steel in a Wide Temperature Range

2013 ◽  
Vol 8 (3) ◽  
pp. 163-167
Author(s):  
Alibek Agazhanov ◽  
Igor Savchenko ◽  
Dmitriy Samoshkin ◽  
Sergey Stankus ◽  
Olga Dutova
Keyword(s):  
Phase Transitions ◽  
Thermal Diffusivity ◽  
Wide Temperature Range ◽  
Curie Point ◽  
Martensitic Steel ◽  
Laser Flash ◽  
Austenite Phase ◽  
Laser Flash Method ◽  
Flash Method ◽  
Temperature Range

Thermal diffusivity of the ferritic-martensitic steel 16Kh12V2FTaR in the temperature range from 296 to 1274 K has been measured by the laser flash method with the error of 2–4 %. The approximating equations have been obtained, the Curie point of steel and the temperatures of martensitic-austenite phase transitions have been determined

Influence of Heat Treatment Process on Tensile Fracture Behavior of Cu-Based Metallic Glass

2013 ◽  
Vol 742 ◽  
pp. 170-174
Author(s):  
Ling Zhang ◽  
De Chun Luo ◽  
Xiang Bin Yi
Keyword(s):  
Tensile Strength ◽  
Fracture Behavior ◽  
Isothermal Annealing ◽  
Flow Behavior ◽  
Performance Testing ◽  
Fracture Morphology ◽  
Test Sample ◽  
Fracture Pattern ◽  
Tensile Fracture ◽  
Venation Pattern

The Cu50Zr42Al8dumbbell-shaped alloy with original scale distance of 25 mm and diameters of 4.5 mm was prepared by the suspend melting-copper mould suction casting. The structure tensile performance testing and the fracture morphology observation of Cu50Zr42Al8BMG as-quenched and 400k/1h isothermal annealing were investigated, respectively. The deformation and fracture behavior of samples had been studied. The results showed that the structure of all samples were composed of amorphous phase and possess good glass formation abilitysample as-quenched is always in the elastic deformation stage during elongation and the tensile strength is 629MPa; however ,for specimen after 400k/1h isothermal annealing ,the yield phenomenon occurs before breaking and the maximum tensile strength is 755Mpa, and the same time, the maximum failure extensibility increases from 0.56% for sample as-quenched to 0.80% for 400k/1h isothermal annealing. The fracture pattern of test sample at annealing assumes venation pattern, which is similar to fractography of Cu50Zr42Al8BMG as-quenched, in addition, which appeared apparent viscous flow behavior and melting characteristics.

Burst Strength of Rotating Discs

1965 ◽  
Vol 180 (1) ◽  
pp. 111-130 ◽  
Author(s):  
N. E. Waldren ◽  
M. J. Percy ◽  
P. B. Mellor
Keyword(s):  
Tensile Strength ◽  
Strain Hardening ◽  
Weight Ratio ◽  
Complex Stress ◽  
True Stress ◽  
Material Strength ◽  
Rotating Disc ◽  
Burst Strength ◽  
Rotating Discs ◽  
Simple Tension

The rotating discs in the aircraft gas turbine engine are components in which the requirement for high strength/weight ratio and the complex stress produced by rotation have a significant influence on material strength and ductility and the study of material behaviour under these conditions has been the subject of numerous investigations. The opportunity to examine the most promising theories for predicting the plastic deformation and fracture of rotating discs arose when a large number of model discs in vacuum melted steel, having near uniform properties, became available for evaluation by burst testing. Fully ductile behaviour of a rotating disc is manifested in the instability phenomenon and correlation between theory and experiment shows that the rotational speed at which instability occurs may be predicted from a knowledge of the true stress-strain curve for the material in simple tension using the Hencky deformation theory. However, due to complex stress resulting from centrifugal loading, fracture in a rotating disc may precede the instability condition and it is not possible to assume fully ductile behaviour in a real material. The plastic stress analysis of model discs in which burst has resulted from fracture prior to instability shows that the materials tested favour a maximum principal stress criterion of fracture and good correlation has been achieved with the maximum true stress at fracture in the tensile test piece. The important influence of strain-hardening on the strength of a rotating disc is demonstrated by the theoretical analysis and by the burst results. For materials exhibiting low strain-hardening the average tangential burst stress in a disc agrees reasonably well with the tensile strength of the material and confirms the simple burst criterion. High strain-hardening materials, however, may be required to exhibit exceptional ductility to allow a disc to achieve a burst strength consistent with the tensile strength and in practical examples relatively low burst strengths have resulted.

Stability of Strength Characteristics of Hardened by Deformation AMg6 Alloy during High-Speed Heating

2020 ◽  
Vol 989 ◽  
pp. 110-115
Author(s):  
Yu.D. Koryagin ◽  
S.I. Il'in ◽  
N.A. Shaburova
Keyword(s):  
Tensile Strength ◽  
Yield Strength ◽  
High Speed ◽  
Cold Deformation ◽  
Amg6 Alloy ◽  
Alloy Amg6 ◽  
Fast Heating ◽  
Temperature Range ◽  
Hardening Effect ◽  
Cold Worked

The results were shown in influence of fast heating parameters on the structure and properties of cold-worked alloy AMg6 with original hot-forged structure. Based on the measured data, the change of mechanical properties of cold-worked alloy AMg6 during the process of short duration heating was evaluated. There was reviewed the role of the temperature and the time of heat on the processes of softening the samples of cold-worked alloy AMg6. The stability of mechanical characteristics of hammer-hardened alloy AMg6 under elevated test temperatures was evaluated. It is shown that the return processes in cold-deformed AMg6 alloy during heating in the temperature range studied receive the most intensive development in the first 5–10 minutes, reducing the hardening effect from cold deformation, determined by tensile strength, respectively: by 8–9% with 100 °C; 26–27% at 150 °C; 37–38% at 200 °C; 42–44% at 250 °C and 50% at 300 °C. A decrease in the yield strength during high-speed heating in the temperature range studied is much faster ,compared with the change in the tensile strength. Hour exposure at 200 °C reduces the hardening effect on the yield strength from 340 MPa to 258 MPa, while the tensile strength decreases from 430 MPa to 385 MPa.

Flow Behavior of 430 Ferritic Stainless Steel at Elevated Temperatures

2013 ◽  
Vol 721 ◽  
pp. 77-81 ◽  
Author(s):  
Jian Bin Zhang ◽  
Dong Mei Yu ◽  
Shao Rui Niu ◽  
Gen Shun Ji
Keyword(s):  
Tensile Strength ◽  
Stainless Steel ◽  
Ferritic Stainless Steel ◽  
Elevated Temperatures ◽  
Flow Behavior ◽  
Engineering Strain ◽  
Tensile Direction ◽  
430 Stainless Steel ◽  
Different Temperatures ◽  
Increasing Temperature

The tensile test of casting ferritic stainless steel was conducted on SHIMADZU AG-10 at different temperatures of 300, 500, 600, 700, 800, and 950°C, respectively. The engineering stress-strain curves with the thermal deformation at the different temperatures, the tensile strength and elongation curves were obtained. Metallographic test samples were prepared and the morphology of deforming zone was observed by optical microscopy. The experimental results showed that the tensile strength of the test samples decreased with increasing temperature. From 300 to 500°C, the work hardening occurred and the tensile strength increased with increasing engineering strain. The softening occurred and the tensile strength decreased with increasing engineering strain at temperatures from 600 to 950°C. The strength of 430 stainless steel decreased, and the plasticity increased with the increase in temperature. The fractures were basically intergranular fractures within the range of 300~950°C. A transition occurred to the form of fracture from the ductile to the brittle, which might be related to the nitrogen atom in the 430. Grain deformation along specimen tensile direction concentrated in the necking region, where appeared banded structure in martensite. The organization at the edge of the sample was fine, while the organization at the central region was coarser.

Characterization of Hot Deformation Behavior of Zr-4 Alloy in Material Application Area

2012 ◽  
Vol 578 ◽  
pp. 202-205
Author(s):  
Guo Qing Lin
Keyword(s):  
Strain Rate ◽  
Hot Deformation ◽  
Deformation Behavior ◽  
Flow Behavior ◽  
Strain Rate Range ◽  
Processing Maps ◽  
Peak Efficiency ◽  
Hot Deformation Behavior ◽  
Rate Range ◽  
Temperature Range

The hot deformation behavior of Zr-4 alloy was studied in the temperature range 650-900°C and strain rate range 0.005-50s-1 using processing maps. The processing maps revealed three domains: the first occurs in the temperature range 780-820°C and strain rate range 0.005-0.05s-1, and has a peak efficiency of 45% at 790°C and 0.005s-1; the mechanism is the dynamic recrystallization. The second occurs in the temperature range greater than 900°C and strain rate range 0.05-0.8s-1, and has a peak efficiency of 40% at 900°C and 0.5s-1, which are the domains of dynamic recovery. In addition, the instability zones of flow behavior can also be recognized by the maps in the temperature range 650-780°C and strain rate range 0.01-0.1s-1, which should be strictly avoided in the processing of the material. Zr-4 alloy is the material for pressure tube applications in nuclear reactors and has better strength and a lower rate of hydrogen uptake compared to other materials under similar service conditions.

Unified Tensile Work Hardening Behaviour of Thin Section Plate and Forged Thick Section 9Cr-1Mo Ferritic Steel

2013 ◽  
Vol 32 (3) ◽  
pp. 287-294
Author(s):  
B.K. Choudhary ◽  
E. Isaac Samuel ◽  
D.P. Rao Palaparti ◽  
J. Christopher ◽  
M.D. Mathew
Keyword(s):  
Plastic Strain ◽  
Strain Rate ◽  
Work Hardening ◽  
Ferritic Steel ◽  
True Stress ◽  
Rate Of Change ◽  
Plastic Strain Rate ◽  
True Plastic Strain ◽  
Temperature Regimes ◽  
Material Conditions

AbstractDetailed investigation has been performed on tensile work hardening behaviour in terms of the variations of instantaneous work hardening rate (θ = dσ/dεp, where σ is true stress and εp is true plastic strain) with stress and true plastic strain rate (ε̇p) for temperature range 300–873 K in two different material conditions, (i) normalised and tempered plate and (ii) quenched and tempered tubeplate forging of 9Cr-1Mo ferritic steel. Both plate and tubeplate forging exhibited two-stage work hardening and three different temperature regimes in the variation of θ with σ. The variations of θ with respect to ε̇p exhibited unified work hardening in terms of a single master curve independent of temperature and initial microstructure. θ varied linearly with reciprocal of plastic strain rate, i.e. 1/ε̇p, and as a consequence, linear correlation between the rate of change of true stress and true plastic strain rate independent of temperature and microstructure has been obtained.

The Effect of Time and Temperature Variations during Isothermal Annealing on the Mechanical Properties of High Carbon Bainitic Steel

2012 ◽  
Vol 706-709 ◽  
pp. 2158-2163 ◽  
Author(s):  
Bartosz Koczurkiewicz
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Industrial Development ◽  
Isothermal Annealing ◽  
Testing Machine ◽  
Mechanical Tests ◽  
Bainitic Steel ◽  
High Carbon ◽  
Temperature Variations ◽  
Temperature Range

The industrial development require new materials characterized highest mechanical properties. The conditions of thermo-mechanical treatment proved to highest level of mechanical properties for steels. Another method of making strong materials is to reduce the scale of the microstructure using heat treatment [1]. The paper presents the results of investigation into the effect of time and temperature variations during isothermal annealing on the mechanical properties of high carbon (c.a. 0,8%C) bainitic steel. Chemical composition of that steel (addition Si, Mn, Mo and Cr) obtain high level of tensile strength and good plastic properties. The analyzing of published results of researches of high carbon bainitic steels shown, that transformation of bainite can take between 2 to 60 days within the temperature range 125÷325°C [2,3] Based on results of researches of investigated steel a isothermal annealing in temperature range 200÷300°C were done. The experiments were done for 24, 50 and 100 hours of annealing. After that the mechanical tests were done. A Zwick Z100 testing machine was used for tests. The force and elongation values were recorded. On their basis, the proof stress and tensile strength of the steel tested were determined as a function of annealing temperature. The microstructure were determinated too.

Sign in / Sign up

Export Citation Format

Share Document