Effects of Strain Rate on Dynamic Strain Aging of SA508-III Steel

The dynamic strain aging (DSA) behavior of SA508-III steel was evaluated through tensile tests with different strain rates from 10-4 to 10-1s-1 at 350°C. The OM, SEM and TEM were carried out to observe the microstructures and fracture morphologies of the steel. The results show that the serrated flows appear in the stress-strain curves when the strain rate is between 10-3~10-2s-1, indicating that DSA occurs. Under the strain rate range, the tensile strength increases and the elongation and the reduction of area decrease. However, the fracture surface of the steel after tensile tests is still ductile. DSA in SA508-III steel at the strain rates from10-3 to 10-2s-1 is mainly caused by the interaction between the internal solute atoms and dislocations, which leads to the dislocations multiplication and the formation of sub-grain boundaries and dislocation cell structure.

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A New Explanation for the Effect of Dynamic Strain Aging on Negative Strain Rate Sensitivity in Fe–30Mn–9Al–1C Steel

Materials ◽

10.3390/ma12203426 ◽

2019 ◽

Vol 12 (20) ◽

pp. 3426 ◽

Cited By ~ 1

Author(s):

Jia Xing ◽

Lifeng Hou ◽

Huayun Du ◽

Baosheng Liu ◽

Yinghui Wei

Keyword(s):

Strain Rate ◽

Strain Rate Sensitivity ◽

Dynamic Strain Aging ◽

Strain Aging ◽

Rate Sensitivity ◽

Tensile Tests ◽

Dynamic Strain ◽

Strain Rates ◽

Dislocation Arrangement ◽

Hall Plot

In this study, the evolution of the mechanical properties of Fe–30Mn–9Al–1C steel has been determined in tensile tests at strain rates of 10−4 to 102 s−1. The results show that the strain rate sensitivity becomes a negative value when the strain rate exceeds 100 s−1 and this abnormal evolution is attributed to the occurrence of dynamic strain aging. Due to the presence of intergranular κ-carbides, the fracture modes of steel include ductile fracture and intergranular fracture. The values of dislocation arrangement parameter M were obtained using a modified Williamson–Hall plot. It has been found that once the strain rate sensitivity becomes negative, the interaction of dislocations in the steel is weakened and the free movement of dislocation is enhanced. Adiabatic heating promotes the dynamic recovery of steel at a high strain rate.

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Effect of SPD processing on mechanical behavior and dynamic strain aging of an Al-Mg alloy in various deformation modes and wide strain rate range

Materials Science and Engineering A ◽

10.1016/j.msea.2017.04.024 ◽

2017 ◽

Vol 696 ◽

pp. 348-359 ◽

Cited By ~ 11

Author(s):

M.A. Valdes-Tabernero ◽

R. Sancho-Cadenas ◽

I. Sabirov ◽

M.Yu Murashkin ◽

I.A. Ovid’ko ◽

...

Keyword(s):

Strain Rate ◽

Mechanical Behavior ◽

Dynamic Strain Aging ◽

Strain Aging ◽

Strain Rate Range ◽

Mg Alloy ◽

Dynamic Strain ◽

Rate Range ◽

Deformation Modes

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Dynamic Strain Aging in the Fe-Mn-Cu-C TWIP Steels

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.668.861 ◽

2013 ◽

Vol 668 ◽

pp. 861-864 ◽

Cited By ~ 3

Author(s):

Hai Jun Liu ◽

Ding Yi Zhu ◽

Xian Peng ◽

Zhen Ming Hu ◽

Ming Jie Wang

Keyword(s):

Mechanical Properties ◽

Strain Rate ◽

Dynamic Strain Aging ◽

Strain Aging ◽

Rate Sensitivity ◽

Tensile Tests ◽

Dynamic Strain ◽

Work Hardening Rate ◽

Twip Steels ◽

High Work

Strain rate jump tests were performed on the Fe-Mn-Cu-C TWIP Steels to determine the strain rate sensitivity, and serrated plastic flow was observed in the stress-strain curves during tensile tests at different constant strain rates ranging from 2.5×10-4S-1 to 2.5×10-2S-1. The Fe-Mn-Cu-C TWIP Steels exhibit high work hardening rate and outstanding mechanical properties, The excellent mechanical properties are attributed to dynamic strain aging(DSA) effect, which result from the interaction between Mn(Cu)-C atom atmosphere, C-vacancy, C-C pairs and moving dislocations.

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The Effect of Slow-Constant Strain Rates on the Tensile Properties of Selected Alloys at Room and Elevated Temperatures

Journal of Engineering Materials and Technology ◽

10.1115/1.3443192 ◽

1974 ◽

Vol 96 (2) ◽

pp. 115-122 ◽

Cited By ~ 7

Author(s):

C. L. Dotson

Keyword(s):

Strain Rate ◽

Elevated Temperatures ◽

Tensile Tests ◽

Strength Properties ◽

Strain Rate Range ◽

Dynamic Strain ◽

Strain Rates ◽

Lower Strain ◽

Temperature Ranges ◽

Design Stress

Tensile tests were performed at constant strain rates from 10−2 to 10−5 min−1 on 5454-O and 1100-O aluminum alloys, A515 Grade 70 steel and B166 nickel alloy at room temperature and at elevated-temperature ranges where the design stress basis normally changes from tensile to creep-rupture controlled. The results in general showed that the strength of the alloys decreased at lower strain rates, and the sensitivity to strain rate was greater at elevated temperatures except where metallurgical phenomena such as dynamic strain aging negate the effects of strain rate. At the highest temperature the decrease in strength properties ranged from 11 to 50 percent over the strain rate range for different alloys.

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A Modified Johnson-Cook Model for Ferritic-Pearlitic Steel in Dynamic Strain Aging Regime

Metals ◽

10.3390/met9050528 ◽

2019 ◽

Vol 9 (5) ◽

pp. 528 ◽

Cited By ~ 2

Author(s):

Ashwin Moris Devotta ◽

P. V. Sivaprasad ◽

Tomas Beno ◽

Mahdi Eynian ◽

Kjell Hjertig ◽

...

Keyword(s):

Flow Stress ◽

Strain Rate ◽

Dynamic Strain Aging ◽

Strain Aging ◽

Experimental Testing ◽

Flow Behavior ◽

Pearlitic Steel ◽

Dynamic Strain ◽

Model Parameters ◽

Strain Rates

In this study, the flow stress behavior of ferritic-pearlitic steel (C45E steel) is investigated through isothermal compression testing at different strain rates (1 s−1, 5 s−1, and 60 s−1) and temperatures ranging from 200 to 700 °C. The stress-strain curves obtained from experimental testing were post-processed to obtain true stress-true plastic strain curves. To fit the experimental data to well-known material models, Johnson-Cook (J-C) model was investigated and found to have a poor fit. Analysis of the flow stress as a function of temperature and strain rate showed that among other deformation mechanisms dynamic strain aging mechanism was active between the temperature range 200 and 400 °C for varying strain rates and J-C model is unable to capture this phenomenon. This lead to the need to modify the J-C model for the material under investigation. Therefore, the original J-C model parameters A, B and n are modified using the polynomial equation to capture its dependence on temperature and strain rate. The results show the ability of the modified J-C model to describe the flow behavior satisfactorily while dynamic strain aging was operative.

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New Approach In The Properties Evaluation Of Ultrafine-Grained OFHC Copper

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0180 ◽

2015 ◽

Vol 60 (2) ◽

pp. 605-614 ◽

Cited By ~ 2

Author(s):

T. Kvačkaj ◽

A. Kováčová ◽

J. Bidulská ◽

R. Bidulský ◽

R. Kočičko

Keyword(s):

Mechanical Properties ◽

Strain Rate ◽

Tensile Tests ◽

Coarse Grained ◽

Wear Behaviour ◽

Ofhc Copper ◽

Strain Rates ◽

Ultrafine Grained ◽

Reduction Of Area ◽

Pin On Disk

AbstractIn this study, static, dynamic and tribological properties of ultrafine-grained (UFG) oxygen-free high thermal conductivity (OFHC) copper were investigated in detail. In order to evaluate the mechanical behaviour at different strain rates, OFHC copper was tested using two devices resulting in static and dynamic regimes. Moreover, the copper was subjected to two different processing methods, which made possible to study the influence of structure. The study of strain rate and microstructure was focused on progress in the mechanical properties after tensile tests. It was found that the strain rate is an important parameter affecting mechanical properties of copper. The ultimate tensile strength increased with the strain rate increasing and this effect was more visible at high strain rates$({\dot \varepsilon} \sim 10^2 \;{\rm{s}}^{ - 1} )$. However, the reduction of area had a different progress depending on microstructural features of materials (coarse-grained vs. ultrafine-grained structure) and introduced strain rate conditions during plastic deformation (static vs. dynamic regime). The wear behaviour of copper was investigated through pin-on-disk tests. The wear tracks examination showed that the delamination and the mild oxidational wears are the main wear mechanisms.

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Behavior of Dynamic Strain Aging in Zr-1.5Nb-0.4Sn-0.2Fe-0.1Cr Alloy Strip

Korean Journal of Metals and Materials ◽

10.3365/kjmm.2021.59.1.8 ◽

2021 ◽

Vol 59 (1) ◽

pp. 8-13

Author(s):

Il-Hyun Kim ◽

Myung-Ho Lee ◽

Yang-Il Jung ◽

Hyun-Gil Kim ◽

Jae-Il Jang

Keyword(s):

Tensile Test ◽

Strain Rate ◽

Dynamic Strain Aging ◽

Strain Aging ◽

Rolling Direction ◽

Rate Sensitivity ◽

Dynamic Strain ◽

Alloy Strip ◽

Lower Strain ◽

Temperature Ranges

The behavior of dynamic strain aging (DSA) in a Zr-1.5Nb-0.4Sn-0.2Fe-0.1Cr alloy strip was investigated at temperature ranges of 25–600 °C via a tensile test. The tensile test was performed at two different strain rates 8.33 × 10-5 and 1.67 × 10-2 s-1. The shear stress of the alloy strip revealed a linear dependency on the test temperature when the specimens were tested under a higher strain rate (1.67 × 10-2 s-1). However, the linear relationship was broken due to DSA when the samples were deformed under a lower strain rate (8.33 × 10-5 s-1). The discrepancy was most significant at 400 °C. The trend in DSA behavior was similar irrespective of the orientation of the samples, i.e., rolling direction (RD) or transverse direction (TD). However, the effect of DSA was larger in the TD samples than the RD samples. The phenomena were interpreted to the variation in work hardening exponents and strain rate sensitivity. The value of the exponent decreased from 0.14 to 0.08 along a RD and from 0.1 to 0.07 along a TD, respectively. However, the smallest value was observed at 400–500 °C irrespective of the specimen orientation, which is consistent with the DSA behavior. It is suggested that the DSA was caused by an interaction of moving dislocations with solute atoms typically oxygen.

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Tensile Stress-Strain Curves Modeling of Four Kinds of Solders with Temperature and Rate Dependence

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.297-300.905 ◽

2005 ◽

Vol 297-300 ◽

pp. 905-911 ◽

Cited By ~ 2

Author(s):

Xu Chen ◽

Li Zhang ◽

Masao Sakane ◽

Haruo Nose

Keyword(s):

Tensile Stress ◽

Constitutive Model ◽

Strain Rate ◽

Constant Strain Rate ◽

Tensile Tests ◽

Strain Rate Range ◽

Rate Dependence ◽

Strain Rates ◽

Stress Strain ◽

Rate Range

A series of tensile tests at constant strain rate were conducted on tin-lead based solders with different Sn content under wide ranges of temperatures and strain rates. It was shown that the stress-strain relationships had strong temperature- and strain rate- dependence. The parameters of Anand model for four solders were determined. The four solders were 60Sn-40Pb, 40Sn-60Pb, 10Sn-90Pb and 5Sn-95Pb. Anand constitutive model was employed to simulate the stress-strain behaviors of the solders for the temperature range from 313K to 398K and the strain rate range from 0.001%sP -1 P to 2%sP -1 P. The results showed that Anand model can adequately predict the rate- and temperature- related constitutive behaviors at all test temperatures and strain rates.

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