Effect of a Minor Sr Modifier on the Microstructures and Mechanical Properties of 7075 T6 Al Alloys

Abstract:Metallic materials have a significant number of applications, among which Al alloys have drawn people's attention due to their low density and high strength. High-strength Al-based alloys, such as 7XXX Al alloys, contain many alloying elements and with high concentration, whose microstructures present casting voids, segregation, dendrites, etc. In this work, a spray deposition method was employed to fabricate an Al-8.31Zn-2.07Mg-2.46Cu-0.12Zr (wt %) alloy with fine structure. The hot deformation behavior of the studied alloy was investigated using a Gleeble 1500 thermal simulator and electron microscopes. The microstructure evolution, variation in the properties, and precipitation behavior were systematically investigated to explore a short process producing an alloy with high property values. The results revealed that the MgZn 2 particles were detected from inside the grain and grain boundary, while some Al 3 Zr particles were inside the grain. An Arrhenius equation was employed to describe the relationship between the flow stress and the strain rate, and the established constitutive equation was that: Figure 7 gives the hardness variations of the hot compressed samples aged at 120 • C fo durations. For the samples after being hot-compressed at strain rates of 1 s −1 and 0.001 s −1 , present the same trend. The initial hardness of compressed samples increased with the hot de temperature. The hardness of the hot-compressed samples increased with the aging time, a kept constant as they were aging at certain temperatures for 15 h.Metals 2017, 7, 299 deformation temperature. The hardness of the hot-compressed samples increased with the and almost kept constant as they were aging at certain temperatures for 15 h. Discussion Constitutive EquationThe constitutive relationships were used to describe the hot deformation behavior. Som are employed to reveal the hot deformation behavior, in which one of the most extended v the hot working constitutive equation is as follows [24]:where ε is the strain rate; A is a material constant which is independent of temperature true stress; Q is the activation energy; R is the gas constant (8.31); and T is the absolute tem (K). At low stress lever (ασ < 0.8):At high stress lever (ασ > 1.2):(σ) σ n F  , β and n are the material constants, α = β/n. Substituting Equations (2) and (3) (4) and (5), respectively, gives:The values of n and β are from the slopes of the lines in ln ε and σ, lnε and ln σ , Discussion Constitutive EquationThe constitutive relationships were used to describe the hot deformation behavior. Som are employed to reveal the hot deformation behavior, in which one of the most extended v the hot working constitutive equation is as follows [24]:where .ε is the strain rate; A is a material constant which is independent of temperature; σ is stress; Q is the activation energy; R is the gas constant (8.31); and T is the absolute tempera At low stress lever (ασ < 0.8):At high stress lever (ασ > 1.2): F(σ) = σ n , β and n are the material constants, α = β/n. Substit...

show abstract

“…[1][2][3][4]. Their excellent performance attracts much interest from the manufacturing industry [5,6].…”

Section: Introductionmentioning

confidence: 99%

Hot Deformation Behavior of a Spray-Deposited Al-8.31Zn-2.07Mg-2.46Cu-0.12Zr Alloy

Sheng

Lei

Xiao

et al. 2017

Metals

View full text Add to dashboard Cite

show abstract

“…A liga ASTM 7075 é considerada um liga metálica de alta resistência da série 7xxx (Al-Zn-Mg-Cu). Tem sido amplamente utilizada para componentes estruturais nas indústrias aeroespacial e automobilística (MA et al, 2017).…”

Section: Introductionunclassified

Desenvolvimento de processos térmicos na liga de alumínio ASTM 7075

Silva¹,

Biehl²,

Medeiros³

et al. 2022

View full text Add to dashboard Cite

O presente trabalho teve como objetivo a determinação das propriedades de dureza, obtidas na liga ASTM 7075, submetida aos tratamentos de solubilização e envelhecimento artificial, com as temperaturas de envelhecimento em 150 °C e 180 °C. O aumento da temperatura visa à redução de tempos de tratamento menores do que os convencionais, permitindo uma maior produção de componentes, a partir desse tratamento. As amostras foram submetidas aos tratamentos térmicos e caracterizadas, antes e depois de cada tratamento, por análise microestrutural, ensaio de dureza e difratometria de raios-X. As amostras envelhecidas artificialmente a 180 °C têm dureza menor do que as envelhecidas a 150 °C. Isso evidencia a importância da distribuição dos precipitados de forma dispersa, contribuindo, mais efetivamente, com as propriedades mecânicas obtidas. Os tempos de envelhecimento, utilizados no estudo, foram de 2, 4, 6 e 8 horas. Esses períodos foram suficientes para atingir o pico de dureza nas curvas de envelhecimento, e as máximas durezas obtidas são compatíveis com as encontradas em outros estudos com esse material. Palavras-chave: ASTM 7075; tratamentos térmicos; envelhecimento.

show abstract

“…With the increasing demand for natural environmental protection and energy conservation, lightweight and intelligence have become an inevitable trend for drilling equipment and tools. The insufficient mechanical properties of conventional steel drill pipes caused by the high density of steel materials pose a challenge to applications of ultra-deep wells as well as long-distance and near-horizontal wells [1]. According to the European Aluminum Association, when weight of the vehicle is reduced by 10%, the fuel consumption can be reduced by 6 % ~ 8 % [2].…”

Section: Introductionmentioning

confidence: 99%

Effect of <i>In Situ</i> TiB<sub>2</sub> Particles on the Grain Size and Mechanical Properties of 7075 Aluminum Alloy

Shao

Wang

Fan

2021

MSF

View full text Add to dashboard Cite

Light-weight and high-strength aluminum alloy drill pipes are potential and promising to replace traditional steel drill pipes. In this study, the grain size and mechanical properties of aluminum alloy drilling pipe materials reinforced by in-situ TiB2 particles were studied. The results showed when reinforced by in-situ TiB2 particles the grain size of aluminum alloy materials was refined from 155 m to 57 m and ultimate tensile strength was increased from 590 MPa to 720 MPa. Besides, the results also indicated that the friction coefficient was reduced from 0.99 to 0.50 and thus the abrasion resistance of 7075 aluminum alloy was enhanced by 34 %. This study provided theoretical basis for the application of light-weight and high-strength aluminum alloy drill pipes in directional drilling and ultra-deep wells.

show abstract

Effect of a Minor Sr Modifier on the Microstructures and Mechanical Properties of 7075 T6 Al Alloys

Cited by 11 publications

References 27 publications

Hot Deformation Behavior of a Spray-Deposited Al-8.31Zn-2.07Mg-2.46Cu-0.12Zr Alloy

Hot Deformation Behavior of a Spray-Deposited Al-8.31Zn-2.07Mg-2.46Cu-0.12Zr Alloy

Desenvolvimento de processos térmicos na liga de alumínio ASTM 7075

Effect of <i>In Situ</i> TiB<sub>2</sub> Particles on the Grain Size and Mechanical Properties of 7075 Aluminum Alloy

Contact Info

Product

Resources

About