Effect of Ag addition on the elevated-temperature mechanical properties of an extruded high strength Mg–Gd–Y–Zr alloy

This paper presents the results of an experimental and statistical study on the effect of high temperatures on the retained mechanical properties of high-strength concretes (HSC). The mechanical properties of HSC significantly change during and later than exposure to elevated temperature. The compressive and splitting tensile strength of more than 400 HSC cylindrical specimens with sixteen mix proportion have investigated to study the effect of mix proportion on the retained mechanical properties of HSC specimens after heating. According to these results, a considerable loss was observed for all mixes and specimens in strength particularly in tensile splitting strength. In addition, these experimental data were investigated using Taguchi approach to find the effective parameters of mix proportion. Also, the most optimum mix proportion was found and checked experimentally. According to our results, by controlling some factors in the mix proportion, it is possible to reduce the retained destructive effects of elevated temperature on HSC specimens.

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Development of a High Strength Mg-Zn-Y-Zr Wrought Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.1701 ◽

2007 ◽

Vol 539-543 ◽

pp. 1701-1706

Author(s):

Rong Shi Chen ◽

Wei Neng Tang ◽

Dao Kui Xu ◽

En Hou Han

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Fatigue Life ◽

Deformation Behavior ◽

Fatigue Behavior ◽

High Strength ◽

Zn Content ◽

High Fatigue ◽

Content Range ◽

Zr Alloy

The effects of Y addition to the Mg-Zn-Y-Zr alloy on the change of the microstructure and the mechanical properties (with the Y content range of 1 to 3 wt%) have been investigated. It shows that when Zn content is constant (5.65wt%), the alloys with Y content between 1.17 and 1.72wt% nearly reach its highest strength. With the composition near the optimums, the extruded Mg-6%Zn-1%Y-Zr alloy shows high strength and excellent ductility. The deformation behavior of this new alloy at high temperature has also been studied. Moreover, the super-long fatigue behavior of the Mg-6%Zn-1%Y-Zr alloy has also been tested, the results show the alloy with a high fatigue strength of about 85-90MPa in the super-long fatigue life regime of 1×109 cycles.

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Effect of High Temperature on Concrete: A Literature Review

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.302-303.138 ◽

2006 ◽

Vol 302-303 ◽

pp. 138-149 ◽

Cited By ~ 4

Author(s):

Gai Fei Peng ◽

Sammy Yin Nin Chan ◽

Qi Ming Song ◽

Quan Xin Yi

Keyword(s):

Experimental Data ◽

Mechanical Properties ◽

High Temperature ◽

Elevated Temperature ◽

Literature Review ◽

High Strength Concrete ◽

High Strength ◽

Research Needs ◽

Standard Fire ◽

Fire Condition

This paper presents a review on the effect of fire on concrete, citing 43 references. It was found that most of them are on the behavior of concrete under high temperature conditions more or less different from the standard fire condition. The problem of spalling, which high-strength concrete encounters when exposed to fire, is especially urgent to solve. Since the literature on the behavior of concrete under fire conditions is very limited, the literature even under elevated temperature has to be used as a part of the base of further research. The further research needs urgently to be carried out under the standard fire condition. Residual mechanical properties reported in most previous literature might be overestimated, where natural cooling was usually employed. Proper evaluation of fire resistance of concrete needs more experimental data obtained under various cooling regimes such as water spraying or water quenching.

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Mechanical properties of high-strength Q960 steel at elevated temperature

Fire Safety Journal ◽

10.1016/j.firesaf.2020.103010 ◽

2020 ◽

Vol 114 ◽

pp. 103010 ◽

Cited By ~ 3

Author(s):

Weiyong Wang ◽

Yanhong Zhang ◽

Lei Xu ◽

Xiang Li

Keyword(s):

Mechanical Properties ◽

Elevated Temperature ◽

High Strength

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A Comparison between Ultra-high-strength and Conventional High-strength Fastener Steels: Mechanical Properties at Elevated Temperature and Microstructural Mechanisms

ISIJ International ◽

10.2355/isijinternational.isijint-2016-120 ◽

2016 ◽

Vol 56 (10) ◽

pp. 1874-1883 ◽

Cited By ~ 5

Author(s):

Carin Emmy Ingrid Christersdotter Ohlund ◽

Mladena Lukovic ◽

Jonathan Weidow ◽

Mattias Thuvander ◽

Sven Erik Offerman

Keyword(s):

Mechanical Properties ◽

Elevated Temperature ◽

High Strength

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Effect of polypropylene fibers on high strength mortar subjected to elevated temperature

E3S Web of Conferences ◽

10.1051/e3sconf/202015605010 ◽

2020 ◽

Vol 156 ◽

pp. 05010

Author(s):

Muhammad Ridwan ◽

Hu Liang Jun ◽

Isamu Yoshitake

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Elevated Temperature ◽

Flexural Strength ◽

Fiber Length ◽

Heating Temperature ◽

High Strength ◽

Polypropylene Fibers ◽

Slump Flow ◽

Residual Mechanical Properties

This study focuses on the thermo-mechanical properties of mortar in the retrofitting cover of additional reinforcement for existing concrete structures. In addition, the residual mechanical properties of high strength mortar incorporating polypropylene fibers subjected to the effect of fiber length and the elevated temperature were investigated. Several experiments were conducted to determine the optimum mixture proportions of high strength mortar incorporating polypropylene fibers which had a slump-flow of 25–30 cm, compressive strength of 50 MPa or higher, and flexural strength of 4–8 MPa. Subsequently, an experiment was conducted by using high-strength mortar-blended polypropylene fibers with a length of 2 cm, and the ratio of fiber length to the diameter of cylinder mortar-specimens was 0.4. The experimental parameters were the weight volume of fibers (0 %, 0.5 %, 1 %, and 2%) and the heating temperature (100, 200 and 300 °C). The effect of the mixing parameters, including polypropylene length on compressive strength, slump-flow and the flexural strength of mortar were discussed. It is evident that fiber in the mortar cover influenced the initial and residual mechanical properties, such as elasticity, compressive strength, and Poisson’s ratio, of the mortar.

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Microstructures and Mechanical Properties of a Novel Mg-Gd-Y-Zn-Zr Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.765.521 ◽

2013 ◽

Vol 765 ◽

pp. 521-524 ◽

Cited By ~ 1

Author(s):

Zhong Yang ◽

Jian Ping Li ◽

Yan Rong Wang ◽

Bi Wei Xiong

Keyword(s):

Mechanical Properties ◽

Elevated Temperature ◽

Uniform Distribution ◽

Hot Extrusion ◽

Microstructure Characteristics ◽

Composition And Structure ◽

Second Phases ◽

Microstructures And Mechanical Properties ◽

Zr Alloy

The microstructure characteristics and mechanical properties of as-cast and hot extruded Mg-5Gd-4Y-0.5Zn-0.5Zr (GWZ540) alloy were investigated. The results show that coarse the as-cast GWZ540 alloy consisted of α-Mg grain and two second phases, disc-like Mg5(Zn0.2Y0.2Gd0.6) and block-shaped Mg24(Y0.6Gd0.4)5. Hot extrusion resulted in a significant refinement of the α-Mg grains and a uniform distribution of the second phases, but with little effect on the composition and structure of the second phases. It is also shown that GWZ540 alloy exhibits higher UTS and TYS and elongation at both room and elevated temperature than those of WE54 alloy.

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