Mechanical properties and fracture features of low-activation ferritic-martensitic steel EK-181 at subzero temperatures

Abstract Berylco 25S alloy is the high-performance beryllium-copper spring material of 2 percent nominal beryllium content. It responds to precipitation-hardening for maximum mechanical properties. It has high elastic and endurance strength, good electrical and thermal conductivity, excellent resistance to wear and corrosion, high corrosion-fatigue strength, good resistance to moderately elevated temperatures, and no embrittlement or loss of normal ductility at subzero temperatures. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Cu-3. Producer or source: Beryllium Corporation.

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Low-Temperature Mechanical Properties of High-Density and Low-Density Polyethylene and Their Blends

Polymers ◽

10.3390/polym13111821 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1821

Author(s):

Ildar I. Salakhov ◽

Nadim M. Shaidullin ◽

Anatoly E. Chalykh ◽

Mikhail A. Matsko ◽

Alexey V. Shapagin ◽

...

Keyword(s):

Mechanical Properties ◽

Low Temperature ◽

Impact Strength ◽

Relative Elongation ◽

High Density ◽

Low Density Polyethylene ◽

Low Density ◽

Elongation At Break ◽

Subzero Temperatures ◽

Izod Impact

Low-temperature properties of high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and their blends were studied. The analyzed low-temperature mechanical properties involve the deformation resistance and impact strength characteristics. HDPE is a bimodal ethylene/1-hexene copolymer; LDPE is a branched ethylene homopolymer containing short-chain branches of different length; LLDPE is a binary ethylene/1-butene copolymer and an ethylene/1-butene/1-hexene terpolymer. The samples of copolymers and their blends were studied by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), 13С NMR spectroscopy, and dynamic mechanical analysis (DMA) using testing machines equipped with a cryochamber. It is proposed that such parameters as “relative elongation at break at −45 °C” and “Izod impact strength at −40 °C” are used instead of the ductile-to-brittle transition temperature to assess frost resistance properties because these parameters are more sensitive to deformation and impact at subzero temperatures for HDPE. LLDPE is shown to exhibit higher relative elongation at break at −45 °C and Izod impact strength at −20 ÷ 60 °C compared to those of LDPE. LLDPE terpolymer added to HDPE (at a content ≥ 25 wt.%) simultaneously increases flow properties and improves tensile properties of the blend at −45 °C. Changes in low-temperature properties as a function of molecular weight, MWD, crystallinity, and branch content were determined for HDPE, LLDPE, and their blends. The DMA data prove the resulting dependences. The reported findings allow one to understand and predict mechanical properties in the HDPE–LLDPE systems at subzero temperatures.

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Engineering mechanical properties by controlling the microstructure of an Fe–Ni–Mn martensitic steel through pre-cold rolling and subsequent heat treatment

Materials Science and Engineering A ◽

10.1016/j.msea.2021.140760 ◽

2021 ◽

Vol 804 ◽

pp. 140760

Author(s):

Hamidreza Koohdar ◽

Pouya Hakimipour ◽

Hamid Reza Jafarian ◽

Terence G. Langdon ◽

Mahmoud Nili-Ahmadabadi

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Cold Rolling ◽

Martensitic Steel ◽

Subsequent Heat Treatment

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Effects of Electroplastic Rolling on Mechanical Properties and Microstructure of Low-carbon Martensitic Steel

Materials Science and Engineering A ◽

10.1016/j.msea.2021.141144 ◽

2021 ◽

pp. 141144

Author(s):

L. Qian ◽

L. Zhan ◽

B. Zhou ◽

X. Zhang ◽

S. Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Martensitic Steel ◽

Low Carbon ◽

Electroplastic Rolling ◽

Carbon Martensitic Steel

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The Effect of Quenching and Partitioning (Q&P) Heat Treatment on the Microstructure and Mechanical Properties of High Boron Steel

Materials ◽

10.3390/ma14061556 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1556

Author(s):

Zhao Li ◽

Run Wu ◽

Mingwei Li ◽

Song-Sheng Zeng ◽

Yu Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Volume Fraction ◽

Martensitic Steel ◽

Boron Steel ◽

Quenching And Partitioning ◽

Effect Mechanism ◽

Microstructure And Mechanical Properties ◽

High Boron ◽

Cast Condition

High boron steel is prone to brittle failure due to the boride distributed in it with net-like or fishbone morphology, which limit its applications. The Quenching and Partitioning (Q&P) heat treatment is a promising process to produce martensitic steel with excellent mechanical properties, especially high toughness by increasing the volume fraction of retained austensite (RA) in the martensitic matrix. In this work, the Q&P heat treatment is used to improve the inherent defect of insufficient toughness of high boron steel, and the effect mechanism of this process on microstructure transformation and the change of mechanical properties of the steel has also been investigated. The high boron steel as-casted is composed of martensite, retained austensite (RA) and eutectic borides. A proper quenching and partitioning heat treatment leads to a significant change of the microstructure and mechanical properties of the steel. The net-like and fishbone-like boride is partially broken and spheroidized. The volume fraction of RA increases from 10% in the as-cast condition to 19%, and its morphology also changes from blocky to film-like. Although the macro-hardness has slightly reduced, the toughness is significantly increased up to 7.5 J·cm−2, and the wear resistance is also improved.

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Structure and mechanical properties of hot-deformed low-carbon martensitic steel

Russian Metallurgy (Metally) ◽

10.1134/s0036029516030113 ◽

2016 ◽

Vol 2016 (3) ◽

pp. 174-180

Author(s):

I. D. Romanov ◽

A. A. Shatsov ◽

M. G. Zakirova ◽

S. K. Berezin

Keyword(s):

Mechanical Properties ◽

Martensitic Steel ◽

Low Carbon ◽

Carbon Martensitic Steel

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Microstructure Evolution and Mechanical Properties of an Al-Cu-Mg Alloy at Elevated Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1004-1005.148 ◽

2014 ◽

Vol 1004-1005 ◽

pp. 148-153

Author(s):

Min Hao ◽

Ji Gang Ru ◽

Ming Liu ◽

Kun Zhang ◽

Liang Wang ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Elevated Temperature ◽

Elevated Temperatures ◽

Shear Fracture ◽

S Phase ◽

Mg Alloy ◽

Transmission Electron ◽

Fracture Features ◽

Scanning Electron

Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to study the microstructure and mechanical behavior of an Al-Cu-Mg alloy after tensile test at 125°C, 150°C, 175°C and 200 °C, respectively. The yield strength and ultimate tensile strength decreased with the increase of temperature, while the elongation increased firstly and then decreased. The S and S′ precipitate after tension at elevated temperatures. When the temperature was higher than 175°C, the precipitate coarsens rapidly. The alloys displayed a shear fracture features at elevated temperature. The larger S′ and S phase coarsened and dropped which forming crack in the grain boundaries and precipitate interfaces, resulting in the decrease of the elongation of the alloy.

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