Effect of specimen size and nickel content on the impact properties of 12 Cr-1 MoVW ferritic steel

Glass/Vinylester composite laminates are comprehensively characterised to assess its impact response behaviour under moisture exposure in marine structures. An instrumented drop weight impact machine is utilised to determine the impact responses of dry and immersed specimens in normal, salted and sea water. The specimens, which had three different thicknesses, were subjected to water exposure for a very long period of over 20 months before tested in a low-velocity impact experiment. Water uptake was measured primarily to study the degradation profiles of GRP laminates after being permeated by water. Matrix dissolution and interfacial damage observed on the laminates after prolonged moisture exposure while the absorption behaviour was found typically non-Fickian. The weight of the composite plates firstly increased because of water diffusion up to month 15 and then decreased due to matrix degradation. The specimens with 3, 6 and 9 mm thickness exhibited maximum water absorption corresponding to 2.6%, 0.7% and 0.5% weight gain, respectively. In general, the results indicated that water uptake and impact properties were affected by thickness and less by water type. Impact properties of prolonged immersed specimens reduced remarkably, and intense failure modes detected almost in all cases. The least sensitive to impact damage were wet specimens with 9 mm thickness as they indicated similar maximum load and absorbed energy for different impact energies.

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Evaluation of Energy Absorption Capabilities of Polyethylene Foam under Impact Deformation

Materials ◽

10.3390/ma14133613 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3613

Author(s):

Baohui Yang ◽

Yangjie Zuo ◽

Zhengping Chang

Keyword(s):

Energy Absorption ◽

Failure Modes ◽

High Strain ◽

Early Stage ◽

High Energy ◽

Test Method ◽

Test Theory ◽

Strain Rates ◽

Impact Properties ◽

The Impact

Foams are widely used in protective applications requiring high energy absorption under impact, and evaluating impact properties of foams is vital. Therefore, a novel test method based on a shock tube was developed to investigate the impact properties of closed-cell polyethylene (PE) foams at strain rates over 6000 s−1, and the test theory is presented. Based on the test method, the failure progress and final failure modes of PE foams are discussed. Moreover, energy absorption capabilities of PE foams were assessed under both quasi-static and high strain rate loading conditions. The results showed that the foam exhibited a nonuniform deformation along the specimen length under high strain rates. The energy absorption rate of PE foam increased with the increasing of strain rates. The specimen energy absorption varied linearly in the early stage and then increased rapidly, corresponding to a uniform compression process. However, in the shock wave deformation process, the energy absorption capacity of the foam maintained a good stability and exhibited the best energy absorption state when the speed was higher than 26 m/s. This stable energy absorption state disappeared until the speed was lower than 1.3 m/s. The loading speed exhibited an obvious influence on energy density.

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Effect of ZrO2 nanoparticles on the impact properties of shielded metal arc welds

Materials Letters ◽

10.1016/j.matlet.2015.05.159 ◽

2015 ◽

Vol 158 ◽

pp. 325-328 ◽

Cited By ~ 10

Author(s):

A.R. Dabiri ◽

R. Yousefi Mojallal ◽

E. Ahmadi ◽

M. Fattahi ◽

S. Amirkhanlou ◽

...

Keyword(s):

Zro2 Nanoparticles ◽

Impact Properties ◽

The Impact

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Effect of different heat-treatment routes on the impact properties of an additively manufactured AlSi10Mg alloy

Materials Science and Engineering A ◽

10.1016/j.msea.2020.140671 ◽

2021 ◽

Vol 802 ◽

pp. 140671

Author(s):

Maverick Giovagnoli ◽

Marialaura Tocci ◽

Annalisa Fortini ◽

Mattia Merlin ◽

Matteo Ferroni ◽

...

Keyword(s):

Heat Treatment ◽

Impact Properties ◽

The Impact

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The impact of transformation plasticity on the electron beam welding of thick-section ferritic steel components

Nuclear Engineering and Design ◽

10.1016/j.nucengdes.2017.03.040 ◽

2017 ◽

Vol 323 ◽

pp. 309-316 ◽

Cited By ~ 18

Author(s):

Anastasia N. Vasileiou ◽

Michael C. Smith ◽

Jeyaganesh Balakrishnan ◽

John A. Francis ◽

Cory J. Hamelin

Keyword(s):

Electron Beam ◽

Ferritic Steel ◽

Electron Beam Welding ◽

Thick Section ◽

Transformation Plasticity ◽

The Impact

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The Microstructure and Property of the Heat Affected zone in C-Mn Steel Treated by Rare Earth

High Temperature Materials and Processes ◽

10.1515/htmp-2017-0175 ◽

2019 ◽

Vol 38 (2019) ◽

pp. 362-369 ◽

Cited By ~ 1

Author(s):

Ming-ming Song ◽

Yu-min Xie ◽

Bo Song ◽

Zheng-liang Xue ◽

Nan Nie ◽

...

Keyword(s):

Rare Earth ◽

Impact Toughness ◽

Heat Affected Zone ◽

Acicular Ferrite ◽

Steel Matrix ◽

Impact Properties ◽

Treated Steel ◽

The Impact ◽

Welding Processes ◽

Mn Steel

AbstractThe microstructures and impact properties of the heat affected zone (HAZ) in steel treated by rare earth (RE) under different welding processes were discussed. The effect of Al on the impact properties of the HAZ in RE treated steel was analyzed. It finds that when the welding t8/5 is smaller than 111 s, the main microstructure in steels is bainite/widmanstatten. The impact toughness of the HAZ is lower than that of the steel matrix. When t8/5 is more than 250 s, the microstructure is mainly acicular ferrite (AF) in the steel treated by RE, and the impact toughness of HAZ is obviously improved. Even under the welding processing with t8/5 about 600 s in RE treated steel can still obtain a lot of AF. While in the steel killed by Al and treated by RE, the main microstructure is parallel cluster of bainite/widmanstatten, and the impact toughness of HAZ is significantly lower than that of low-Al RE treated steel. Al can deteriorate the optimizing of RE treatment on HAZ.

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