Microstructural Scale Effects on Fatigue of Aluminum Alloys
نویسنده
چکیده
ABSRACT A comparative study of the surface microstructural changes after fatigue in an ultrafine grained and coarse grained aluminum alloy was performed using orientation imaging microscopy (OIM). The fraction of low angle boundaries with misorientation less than 2.5 ̊ increased for both the coarse and ultrafine grained alloys. A consistent decrease in the fraction of low angle boundaries, with misorientation between 2.5 ̊ and 15 ̊, for ultrafine grained alloy was noted. The results are discussed on the basis of an analytical model of deformation for ultrafine grained metals.
منابع مشابه
Fatigue Life Prediction in Aluminum Shape Castings
Increasing use of aluminum shape castings in automotive and aerospace industries has drawn great attention to fatigue properties of cast aluminum components. The fatigue resistance of aluminum castings strongly depends upon the presence of casting flaws and characteristics of microstructural constituents. The existence of casting flaws significantly reduces fatigue crack initiation life. In the...
متن کاملPorosity Control and Fatigue Behavior in A356-T61 Aluminum Alloy
Much work has been done, in recent years, to characterize the factors that cause porosity in aluminum castings, and to analyze the impact of porosity or microstructural parameters on fatigue life. What has yet to be done is systematically separate out the effects of dendrite arm spacing and largest pore size from each other, and from the underlying chemical and process parameters that influence...
متن کاملParticle size, volume fraction and matrix strength effects on fatigue behavior and particle fracture in 2124 aluminum-SiCp composites
The effects of particle size, volume fraction and matrix strength on the stress-controlled axial fatigue behavior and the probability of particle fracture were evaluated for 2124 aluminum alloy reinforced with SiC particles. Average particle sizes of 2, 5, 9 and 20/~m and volume fractions of 0.10, 0.20 and 0.35 were examined for four different microstructural conditions. Tensile and yield stren...
متن کاملEffects of Various Ageing Heat Treatments on Microstructural Features and Hardness of Piston Aluminum Alloy
Piston aluminum alloys have different intermetallic phases, such as Cu3Al, Mg2Si ,and AlNi phases. The morphology and the distribution of such phases have important roles on mechanical properties of the piston material. Therefore, in this research, various ageing heat treatments on the mentioned material were done and the microstructural feature and the hardness were studi...
متن کاملOnset Frequency of Fatigue Effects in Pure Aluminum and 7075 (AlZnMg) and 2024 (AlCuMg) Alloys
The viscoelastic response of pure Al and 7075 (AlZnMg) and 2024 (AlCuMg) alloys, obtained with a dynamic-mechanical analyzer (DMA), is studied. The purpose is to identify relationships between the viscoelasticity and fatigue response of these materials, of great interest for structural applications, in view of their mutual dependence on intrinsic microstructural effects associated with internal...
متن کامل