Interaction between plastic deformation and hydrogen damage behavior of 30CrMnSiNi2A steel

The interaction between plastic deformation and hydrogen damage behavior of 30CrMnSiNi2A steel was investigated by pre-strain tensile tests and hydrogen charging by electrochemical method. This paper mainly contains two parts. The plastic deformation was restrained by hydrogen-charged, and the effect of hydrogen brittleness damage behavior was accelerated by pre-plastic deformation measure. Tensile pre-strian tests with hydrogen charging at current density from 0 to 50 mA/cm2 for 120 min were performed at room temperature. Both rate of reduction in areaand elongation were decreased due to the transition from ductile to brittle fracture by hydrogen charging, which meant the ability of plastic deformation was reduced by hydrogen. With hydrogen concentration increasing, yield strength also increased indicating that the plastic deformation forming conditions of steel were improved by hydrogen. Hydrogen content increased with pre-strain measured by glycerol gas collection method. Due to the pre-strain measure before hydrogen charging, the reduction of area and elongation were further reduced, while the strength was unexpectedly low. It was because pre-strain promoted the formation of hydrogen-induced crackings (HIC). This proved that the plastic deformation promoted the generation of hydrogen damage.

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High Temperature Plasticity of TP347H Stainless Steel Welded Joint Heat Affected Zone

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.881.19 ◽

2021 ◽

Vol 881 ◽

pp. 19-24

Author(s):

Zhong Bing Chen ◽

Qiu Hua Zhu ◽

Jian Xing Song ◽

Yan Liu

Keyword(s):

Plastic Deformation ◽

Stainless Steel ◽

High Temperature ◽

Grain Boundary ◽

Heat Affected Zone ◽

Welded Joint ◽

Tensile Tests ◽

Peak Temperature ◽

Thermal Cycles ◽

Reduction Of Area

Simulated Heat Affected Zone (HAZ) samples of TP347H stainless steel welded joint with 800-1380°C peak temperature thermal cycles were produced using Gleeble 3180 thermal mechanical simulator. 600°C constant speed tensile tests for simulated HAZ samples were carried out, and the precipitates of the simulated samples were analyzed by EDAX. The results show that the lowest Reduction of Area (RoA) was around 53% - 56% in 900-1150°C, which was about 15% lower than the maximum RoA in 800-1380°C. The reasons for decrease of HAZ high temperature plasticity were related to the precipitation of NbC. The fine NbC precipitated in the crystal and grain boundary enhanced strength of grain at high temperature, which resulted plastic deformation or slip at high temperature were mainly concentrated in the grain boundary, and high temperature plasticity of HAZ were decreased.

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Mechanical Properties of Aluminium Processed by ECAP

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.114.39 ◽

2006 ◽

Vol 114 ◽

pp. 39-44

Author(s):

Rafal M. Molak ◽

Zbigniew Pakiela

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Plastic Strain ◽

Room Temperature ◽

Tensile Tests ◽

Large Plastic Strain ◽

Angular Pressing ◽

Purity Aluminium ◽

High Purity Aluminium ◽

The Relationship

The aim of this study was to investigate the influence of large plastic strain on the microstructure and mechanical properties of aluminium processed by severe plastic deformation (SPD) by the Equal Channel Angular Pressing (ECAP) method. Polycrystalline high purity aluminium (99,99%) was pressed at room temperature to produce samples subjected to 4, 8 and 12 ECAP passes. The microstructure of aluminium was examined using a light polarized microscope. Microhardness measurements and tensile tests were undertaken to determine the mechanical properties of the material processed by ECAP. The results obtained show the relationship between the microstructure and the mechanical properties of the material.

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Mechanical Properties of Extruded and ECAP Processed Magnesium Alloy AZ91 at Elevated Temperature

Materials Science Forum ◽

10.4028/www.scientific.net/msf.891.366 ◽

2017 ◽

Vol 891 ◽

pp. 366-371 ◽

Cited By ~ 2

Author(s):

Roman Štěpánek ◽

Libor Pantělejev ◽

Ehsan Mostaed ◽

Maurizio Vedani

Keyword(s):

Mechanical Properties ◽

Elevated Temperature ◽

Magnesium Alloy ◽

Room Temperature ◽

Tensile Tests ◽

Az91 Magnesium Alloy ◽

Magnesium Alloy Az91 ◽

Az91 Magnesium ◽

Reduction Of Area ◽

Increasing Temperature

In this paper tensile properties at elevated temperature of extruded AZ91 magnesium alloy and the same alloy further processed by ECAP (exECAP) are compared. The tensile tests were performed at room temperature and for the temperature range of 100 to 300 °C. Loading speed 2 mm/min was used for the tests. At room temperature mechanical properties except elongation were slightly higher for extruded material yet still very similar to properties of exECAPed material. Overall trend of properties evolution with increasing temperature was also similar but the decrease of strength or the increase of elongation and reduction of area respectively is more intensive for exECAPed material. Elongation of exECAPed material exceeded elongation of extruded material more than twice at 300 °C and with value of ~260% this alloy exhibited pseudosuperplastic behavior.

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Electron microscope studies of the plastic deformation of ternary alloys based on GaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100178732 ◽

1990 ◽

Vol 48 (4) ◽

pp. 1120-1120

Author(s):

R. Haswell ◽

U. Bangert ◽

P. Charsley

Keyword(s):

Plastic Deformation ◽

Electron Microscope ◽

Room Temperature ◽

Stacking Faults ◽

The Other ◽

Ternary Alloys ◽

Dislocation Mobility ◽

Semiconducting Materials ◽

Micro Indentation

A knowledge of the behaviour of dislocations in semiconducting materials is essential to the understanding of devices which use them . This work is concerned with dislocations in alloys related to the semiconductor GaAs . Previous work on GaAs has shown that microtwinning occurs on one of the <110> rosette arms after indentation in preference to the other . We have shown that the effect of replacing some of the Ga atoms by Al results in microtwinning in both of the rosette arms.In the work to be reported dislocations in specimens of different compositions of Gax Al(1-x) As and Gax In(1-x) As have been studied by using micro indentation on a (001) face at room temperature . A range of electron microscope techniques have been used to investigate the type of dislocations and stacking faults/microtwins in the rosette arms , which are parallel to the [110] and [10] , as a function of composition for both alloys . Under certain conditions microtwinning occurs in both directions . This will be discussed in terms of the dislocation mobility.

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A comparative study of plastic deformation mechanisms in room-temperature and cryogenically deformed magnesium alloy AZ31

Materials Science and Engineering A ◽

10.1016/j.msea.2021.140821 ◽

2021 ◽

Vol 807 ◽

pp. 140821

Author(s):

Kai Zhang ◽

Zhutao Shao ◽

Christopher S. Daniel ◽

Mark Turski ◽

Catalin Pruncu ◽

...

Keyword(s):

Plastic Deformation ◽

Magnesium Alloy ◽

Comparative Study ◽

Room Temperature ◽

Deformation Mechanisms ◽

Alloy Az31 ◽

Magnesium Alloy Az31

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Influence of Hydrostatic Extrusion on the Mechanical Properties of the Model Al-Mg Alloys

Journal of Materials Engineering and Performance ◽

10.1007/s11665-021-05628-0 ◽

2021 ◽

Author(s):

Aleksandra Towarek ◽

Wojciech Jurczak ◽

Joanna Zdunek ◽

Mariusz Kulczyk ◽

Jarosław Mizera

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Tensile Strength ◽

Microstructural Analysis ◽

Tensile Tests ◽

Hydrostatic Extrusion ◽

Microstructure Formation ◽

Initial State ◽

Degree Of Deformation ◽

Al Mg Alloys

AbstractTwo model aluminium-magnesium alloys, containing 3 and 7.5 wt.% of Mg, were subjected to plastic deformation by means of hydrostatic extrusion (HE). Two degrees of deformation were imposed by two subsequent reductions of the diameter. Microstructural analysis and tensile tests of the materials in the initial state and after deformation were performed. For both materials, HE extrusion resulted in the deformation of the microstructure—formation of the un-equilibrium grain boundaries and partition of the grains. What is more, HE resulted in a significant increase of tensile strength and decrease of the elongation, mostly after the first degree of deformation.

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GRAIN REFINEMENT AND MICROSTRUCTURE EVOLUTION IN ALUMINUM A2618 ALLOY BY HIGH-PRESSURE TORSION

Jurnal Teknologi ◽

10.11113/jt.v78.9163 ◽

2016 ◽

Vol 78 (6-9) ◽

Author(s):

Intan Fadhlina Mohamed ◽

Seungwon Lee ◽

Kaveh Edalati ◽

Zenji Horita ◽

Shahrum Abdullah ◽

...

Keyword(s):

Plastic Deformation ◽

High Pressure ◽

Grain Refinement ◽

Room Temperature ◽

Rotation Speed ◽

High Pressure Torsion ◽

Applied Pressure ◽

Saturation Level ◽

Microstructural Refinement ◽

Average Grain Size

This work presents a study related to the grain refinement of an aluminum A2618 alloy achieved by High-Pressure Torsion (HPT) known as a process of Severe Plastic Deformation (SPD). The HPT is conducted on disks of the alloy under an applied pressure of 6 GPa for 1 and 5 turns with a rotation speed of 1 rpm at room temperature. The HPT processing leads to microstructural refinement with an average grain size of ~250 nm at a saturation level after 5 turns. Gradual increases in hardness are observed from the beginning of straining up to a saturation level. This study thus suggests that hardening due to grain refinement is attained by the HPT processing of the A2618 alloy at room temperature.

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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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