A study on fracture toughness and strain rate sensitivity of severely deformed Al 6063 alloys processed by multiaxial forging and rolling at cryogenic temperature

Vendra, S.S. Lokesh; Goel, Shivani; Kumar, Nikhil; Jayaganthan, R.

doi:10.1016/j.msea.2017.01.035

Cited by 51 publications

(11 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rao et al [ 16 ] found that AA6061 possessed composite like structure with both lamellar and equiaxed grains when subjected to MAF for three cycles at 77 K, and the hardness was improved greatly. Vendra et al [ 85 ] demonstrated that the cryo‐MAF improved the hardness and UTS of AA6063 due to the multimodal microstructure which composed of nanocrystalline, ultrafine, and coarse grains. Figure shows the variation in UTS, YS, and elongation for a cryo‐forged AA2014 after different cycles, reported by Joshi.…”

Section: Cryo‐forming Techniquesmentioning

confidence: 99%

“…Yu et al [ 29 ] first used ACR to produce nanostructured AA1170 sheets composed of grains of 211 nm, while the grain size was 500 nm in sheets processed at RT. Vendra et al [ 85 ] demonstrated that the forging under cryogenic condition can be used to fabricate a multimodal microstructure composed of nanocrystalline, ultrafine, and coarse grains, thus improving hardness and UTS of AA6063. For commercial purity aluminum, Pachla et al [ 65 ] reported that the average grain size was reduced to 400 nm after cryogenic extrusion, the YS was 168 MPa, and the elongation reached 13.6%.…”

Section: Microstructure Evolution Mechanism Of Al Alloys Via Cryo‐formingmentioning

confidence: 99%

See 1 more Smart Citation

Development of High Performance of Al Alloys via Cryo‐Forming: A Review

Xiong

Su²,

Kong

et al. 2021

Adv Eng Mater

View full text Add to dashboard Cite

Weight reduction is a major trend in the development of automotive, marine, and aerospace industry. Al alloys are the ideal choice for the lightweight design because of their superior mechanical properties and small mass density. In recent years, research results have demonstrated that plastic processing at cryogenic temperature can improve the mechanical properties of Al alloys. Herein, the mechanical properties of Al alloys at cryogenic environment as well as at room temperature are compared, and then the main progress is introduced in the development of fabrication of high‐performance Al alloys using cryo‐forming methods, such as cryorolling, asymmetric cryorolling, cryo‐extrusion, and cryo‐forging, with subsequent heat treatment. The grain refinement mechanism and the strengthening mechanism of Al alloys during various cryo‐forming processes are discussed. Finally, the potential development prospects of future researches in this field are proposed.

show abstract

Section: Cryo‐forming Techniquesmentioning

confidence: 99%

Section: Microstructure Evolution Mechanism Of Al Alloys Via Cryo‐formingmentioning

confidence: 99%

Development of High Performance of Al Alloys via Cryo‐Forming: A Review

Xiong

Su²,

Kong

et al. 2021

Adv Eng Mater

View full text Add to dashboard Cite

show abstract

“…When it comes to making critical parts from special metal materials using this method, then, when they are deformed, there is a risk to decrease the stability, as well as to significantly increase the loads on the tool [7][8][9][10][11]. Therefore, it is important to implement this process in narrow temperature and speed conditions, under which short-term creep of the material takes place [12][13][14][15]. In this case, such factors as the velocity and time of deformation determine the modes of technology application and need to be calculated.…”

Section: Introductionmentioning

confidence: 99%

Formation of bulges on hollow cylindrical products made of non-ferrous difficult-to-deform alloys

Ларин

Пасынков

2020

MATEC Web Conf.

View full text Add to dashboard Cite

Formation of thickened elements on the edge parts of hollow cylindrical products, which serve as the elements of fuel lines of various power plants, can be applied to ensure a significant quality of their welding connection. The article deals with the formation of such thickening elements on tubes made of special non-ferrous alloys. Due to the mechanical features of these materials, these processes were investigated under narrow temperature and speed conditions causing short-term creep of the material. To analyze these operations, mathematical models have been created that describe power modes. Quantitative rules of the influence of the geometric parameters of the process on the pressure during the upsetting have been obtained. The materials obtained during the analysis can be used to create similar technologies.

show abstract

“…Thus, dynamic recovery which is associated with high/medium stacking fault energy metals and alloys limits the generation of dislocation boundaries and hinders grain refinements [15]. The reports of previous research studies showed that SPD at cryogenic temperature has a substantial effect in refining the microstructure [17]. At the liquid nitrogen temperature, dynamic recovery is suppressed which leads to accumulate high density of dislocations and the formation of ultrafine grains [14].…”

Section: Introductionmentioning

confidence: 99%

“…Accordingly, cryogenic SPD requires less amount of plastic deformation energy for generating UFG structure in comparison with the SPD processes at room temperature [18]. There are some studies regarding microstructures and mechanical properties of aluminum alloys processed by MAF at cryogenic temperature [14,17,18]. Singh et al [18] studied the simultaneous improvement of strength and ductility as well as the corrosion resistance of ultrafine grained AA2024 processed by multiaxial cryoforging and cryorolling followed by aging.…”

Section: Introductionmentioning

confidence: 99%

High Strain Rate Behavior of Ultrafine Grained AA2519 Processed via Multi Axial Cryogenic Forging

Azimi

Owolabi

Fallahdoost

et al. 2019

Metals

Self Cite

View full text Add to dashboard Cite

The present work deals with studies on the dynamic behavior of ultrafine grained AA2519 alloy synthesized via cryogenic forging (CF) and room temperature forging (RTF) techniques. A split-Hopkinson pressure bar was used to perform high strain rate tests on the processed samples and the microstructures of the samples were characterized before and after impact tests. Electron backscatter diffraction (EBSD) maps demonstrated a significant grain size refinement from ~740 nm to ~250 nm as a result of cryogenic plastic deformation showing higher dislocation densities and stored strains in the CF sample when compared to the RTF sample. This microstructure modification caused the increase of dynamic flow stress in this alloy. In addition, the aluminum matrix of the CF alloy is more densely populated with fragmented particles than the RTF alloy due to the heavier plastic deformation applied to the cryogenically forged alloy. The results obtained from the stress–strain curve for the RTF sample showed intense thermomechanical instabilities in the RTF sample which led to a severe thermal softening and the subsequent sharp drop in the flow stress. However, no significant decrease was observed in the stress–strain curve of the CF alloys with ultrafine grains which means that thermal softening would probably not be the most effective failure mechanism. Furthermore, higher level of sensitivity of CF alloys to strain rates was observed which is ascribed to transition of rate-controlling plastic deformation mechanisms. In the post-mortem microstructure investigation, deformed and transformed adiabatic shear bands (ASBs) were identified on the RTF alloy when the strain rate is over 4000 s−1 at which it had experienced a significant thermal softening. On the other hand, circular path and aligned split arcs are the various shapes of the deformed ASB seen at no earlier than 4500 s−1 in the CF alloys. This is associated with the crack failure caused by grain boundary sliding.

show abstract

A study on fracture toughness and strain rate sensitivity of severely deformed Al 6063 alloys processed by multiaxial forging and rolling at cryogenic temperature

Cited by 51 publications

References 37 publications

Development of High Performance of Al Alloys via Cryo‐Forming: A Review

Development of High Performance of Al Alloys via Cryo‐Forming: A Review

Formation of bulges on hollow cylindrical products made of non-ferrous difficult-to-deform alloys

High Strain Rate Behavior of Ultrafine Grained AA2519 Processed via Multi Axial Cryogenic Forging

Contact Info

Product

Resources

About