The mass saving potential of light-weight materials, such as Al alloys, is beneficial for fuel economy and reducing CO2 emissions. However, the wide-spread use of these alloys has been long hindered due to the difficulty in fusion joining as well as their high cost. Welding of Al alloys, which are considered to be difficult to weld through conventional arc welding, is now possible by either of low heat input arc welding, high-power density fusion joining, such as laser beam welding and electron beam welding, or friction stir welding. Particularly, friction stir welding can be successfully applied to these materials owing to the fact that no melting takes place in the weld nugget. The aim of this overview is to summarize the developments in the joining of Al alloys over the recent years. This study is also intended to provide guidance for the industry and researchers dealing with joining of these alloys.

Recent developments in joining of aluminum alloys

https://hal.archives-ouvertes.fr/hal-01832872/document

Segregation assisted grain boundary precipitation in a model Al-Zn-Mg-Cu alloy

Joining of carbon fibre reinforced polymer (CFRP) composites and aluminium alloys – A review Part A Applied science and manufacturing

Quantitative study of the corrosion evolution and stress corrosion cracking of high strength aluminum alloys in solution and thin electrolyte layer containing Cl

7XXX series aluminum alloys (Al 7XXX alloys) are widely used in bearing components, such as aircraft frame, spars and stringers, for their high specific strength, high specific stiffness, high toughness, excellent processing, and welding performance. Therefore, Al 7XXX alloys are the most important structural materials in aviation. In this present review, the development tendency and the main applications of Al 7XXX alloys for aircraft structures are introduced, and the existing problems are simply discussed. Also, the heat treatment processes for improving the properties are compared and analyzed. It is the most important measures that optimizing alloy composition and improving heat treatment process are to enhance the comprehensive properties of Al 7XXX alloys. Among the method, solid solution, quenching, and aging of Al 7XXX alloys are the most significant. We introduce the effects of the three methods on the properties, and forecast the development direction of the properties, compositions, and heat treatments and the solution to the corrosion prediction problem for the next generation of Al 7XXX alloys for aircraft structures. The next generation of Al 7XXX alloys should be higher strength, higher toughness, higher damage tolerance, higher hardenability, and better corrosion resistance. It is urgent requirements to develop or invent new heat treatment regime. We should construct a novel corrosion prediction model for Al 7XXX alloys via confirming the surface corrosion environments and selecting the accurate and reliable electrochemical measurements.

The Advancement of 7XXX Series Aluminum Alloys for Aircraft Structures: A Review

Stress corrosion cracking behaviour of 7xxx aluminum alloys: A literature review

Purpose




The purpose of this study is to manufacture test boards for re-enacting plant or field situations where vacuum chamber for expelling gas bubbles and autoclave equipment would not be accessible. This research focuses on the examination and enhancement of tensile strength for the nanocomposites consisting of uniaxial glass fiber mats, nanoclay (NC) and epoxy.




Design/methodology/approach




The parameters considered are the weight content of Cloisite 15A NC, the volume of glass fiber (Vgf) and the direction of glass fibers (θ). The composites are made by hand lay-up technique and tested according to ASTM D 638 standard. Taguchi L9 orthogonal array is used to design the experiments.




Findings




The results imply that the orientation of fibers exhibited high significance with a p-value of 0.001 for the upgrade of strength. NC percentage and the volume of fiber have a low effect as the p-values obtained were 0.375 and 0.294. Confirmation tests were performed at the optimal levels of parameters and the outcomes were in the permissible range of the anticipated values of S/N ratio and mean tensile strength. The negligible effect of nanoclay is due to the lack of infusion of resin into the d-spacing of clay layers due to the low configuration settings of mixing conditions which was confirmed by XRD studies. The negligible effect of glass fiber volume is due to the void content and lack of stress transfer between fibers uniformly due to the void content and improper mixing of nanoclay.




Research limitations/implications




The limitation of this study is that a low-speed mechanical stirrer was used to mix NC in the epoxy and the mixture was not subjected to vacuum and ultrasonication for degassing and deagglomeration.




Practical implications




These composites can be used as substitute materials in place of metallic parts in the aerospace and automobile sector. These composites can be used in civil structures instead of steel and concrete, which have low strength-to-weight ratio and where the requirement of strength is in the range of 60 to 390 MPa.




Social implications




The composites can be used in a variety of applications, for example, structural works, automotive panels and low-cost housing.




Originality/value




This research gives an idea about the combined contribution of NC, Vgf and “θ” to the improvement of tensile strength of the glass-epoxy composite.

Effect of nanoclay, glass fiber volume and orientation on tensile strength of epoxy-glass composite and optimization using Taguchi method

Mechanical properties of tungsten carbide nanoparticles filled epoxy polymer nano composites

Influence of Cold Rolling and Annealing on the Tensile Properties of Aluminum 7075 Alloy

Cold rolling of the titanium alloy Timetal 834 was found to cause marked enhancement in low-cycle fatigue (LCF) life at low strain amplitude and to eliminate bilinear behavior from the Coffin–Manson (C-M) relationship. It was due to work hardening of surface grains of soft orientation and consequent increase in resistance of the material against crack initiation. The observed effect was not associated with texture.

K.V. Sai Srinadh

Papers

Stress corrosion cracking behaviour of 7xxx aluminum alloys: A literature review

Effect of nanoclay, glass fiber volume and orientation on tensile strength of epoxy-glass composite and optimization using Taguchi method

Mechanical properties of tungsten carbide nanoparticles filled epoxy polymer nano composites

Influence of Cold Rolling and Annealing on the Tensile Properties of Aluminum 7075 Alloy

Elimination of Dual Slope from the Coffin–Manson Relationship of Low-Cycle Fatigue in the Titanium Alloy Timetal 834, by Cold Rolling