Processing of V65 Aluminium Alloy Wires Processed from Hot and Warm Rolled Rods for Rivet Applications

2012 ◽  
Vol 710 ◽  
pp. 174-179
Author(s):  
Niraj Nayan ◽  
S.V.S. Narayana Murty ◽  
S.C. Sharma ◽  
Parameshwar Prasad Sinha
Keyword(s):  
Aluminium Alloy ◽  
Vacancy Concentration ◽  
Natural Aging ◽  
High Plasticity ◽  
Potential Candidate ◽  
2024 Alloy ◽  
Treat Ment ◽  
Aa 2024 ◽  
Aging Kinetics

High shear strength of 25 kg/mm2 combined with a high plasticity makes Russian grade V65 aluminum alloys as potential candidate compared to AA2024 for riveting applications in aerospace industries. The lower content of magnesium over the AA 2024 alloy decreases the aging kinetics of this alloy because of the decreased vacancy concentration in the as-quenched alloy which in turn gives flexibility to carryout riveting operation even after 4 days after solution heat treat¬ment and natural aging at room temperature. This paper presents the processing and characterization of V65 aluminium alloy wires processed from hot and warm rolled rods. Mechanical properties of the wires have been evaluated in T6 and T4 tempers and correlated with microstructures. Detailed microstructural examination using optical microscopy and fractography of the tensile tested samples using scanning electron microscopy were carriedout.

Processing and Characterization of Al-Cu-Mg Alloy Rivets for Aerospace Applications

2012 ◽  
Vol 710 ◽  
pp. 180-185 ◽  
Author(s):  
Niraj Nayan ◽  
S.V.S. Narayana Murty ◽  
Alok Agarwal ◽  
S.C. Sharma ◽  
P.P. Sinha
Keyword(s):  
Shear Strength ◽  
Aluminium Alloy ◽  
Cold Working ◽  
Cold Work ◽  
Mg Alloy ◽  
High Plasticity ◽  
High Shear ◽  
Aerospace Applications ◽  
High Shear Strength

Al-Cu-Mg (Russian grade V65) alloys are used for riveting applications in aerospace industries due to their relatively high shear strength of the order of 25 kg/mm2 combined with a high plasticity. This paper presents the processing of V65 aluminium alloy rivets from wire rods. It was observed that wire rods which have not been intermittently annealed and having more than 25% cold working prior to heading operation, cracked on the free bulged surface of the head. In view of this, it is recommended that a maximum of 25% of cold work is allowed in the wire rods to be used for rivet fabrication to successfully realize defect free rivets.

Processing of Al-Cu-Mg Alloy (V65 Grade) Bars as Feedstock for Wire Drawing

2012 ◽  
Vol 710 ◽  
pp. 167-173 ◽  
Author(s):  
Niraj Nayan ◽  
S.V.S. Narayana Murty ◽  
Abhay Kumar Jha ◽  
S.C. Sharma ◽  
K. Sreekumar ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Solution Treatment ◽  
Natural Aging ◽  
Wire Drawing ◽  
Direct Chill ◽  
High Plasticity ◽  
Aging Response ◽  
Different Temperatures ◽  
Aging Kinetics ◽  
Kinetics Of

Al-Cu-Mg (Russian grade V65) alloys are used for riveting applications in aerospace industries due to relatively high shear strength of the order of 25 kg/mm2 combined with a high plasticity. The main advantage of using V65 aluminum alloy for rivet application comes from its significantly slower natural aging response, which gives flexibility to carryout riveting operation even after 4 days after solution heat treatment and natural aging at room temperature. This very valuable feature is not found in its counterpart alloy AA2024 where due to rapid aging kinetics of this alloy, the riveting operation must be completed within 30 min of the solution treatment, which is many times impractical. This paper presents the processing of V65 aluminium alloy by Direct Chill (DC) casting followed by subsequent secondary processing through extrusion and forging to realize feedstock for caliber rolling. These ingots were caliber rolled to 12 mm diameter rods at different temperatures and mechanical properties were evaluated in T6 and T4 tempers. Detailed microstructural examination using optical microscopy and fractography of the tensile tested samples using scanning electron microscopy were carriedout to correlate microstructure and mechanical properties.

scholarly journals Longitudinal Characterization of the Gut Bacterial and Fungal Communities in Yaks

2021 ◽  
Vol 7 (7) ◽  
pp. 559
Author(s):  
Yaping Wang ◽  
Yuhang Fu ◽  
Yuanyuan He ◽  
Muhammad Fakhar-e-Alam Kulyar ◽  
Mudassar Iqbal ◽  
...  
Keyword(s):  
Natural Aging ◽  
Fungal Communities ◽  
Significant Shift ◽  
Mature Adult ◽  
Bacterial Phyla ◽  
Development Stages ◽  
Composition And Structure ◽  
Intestinal Functions ◽  
Development Phases

Development phases are important in maturing immune systems, intestinal functions, and metabolism for the construction, structure, and diversity of microbiome in the intestine during the entire life. Characterizing the gut microbiota colonization and succession based on age-dependent effects might be crucial if a microbiota-based therapeutic or disease prevention strategy is adopted. The purpose of this study was to reveal the dynamic distribution of intestinal bacterial and fungal communities across all development stages in yaks. Dynamic changes (a substantial difference) in the structure and composition ratio of the microbial community were observed in yaks that matched the natural aging process from juvenile to natural aging. This study included a significant shift in the abundance and proportion of bacterial phyla (Planctomycetes, Firmicutes, Bacteroidetes, Spirochaetes, Tenericutes, Proteobacteria, and Cyanobacteria) and fungal phyla (Chytridiomycota, Mortierellomycota, Neocallimastigomycota, Ascomycota, and Basidiomycota) across all development stages in yaks. As yaks grew older, variation reduced, and diversity increased as compared to young yaks. In addition, the intestine was colonized by a succession of microbiomes that coalesced into a more mature adult, including Ruminococcaceae_UCG-005, Romboutsia, Prevotellaceae_UCG-004, Blautia, Clostridium_sensu_stricto_1, Ruminococcus_1, Ruminiclostridium_5, Rikenellaceae_RC9_gut_group, Alloprevotella, Acetitomaculum, Lachnospiraceae_NK3A20_group, Bacteroides, Treponema_2, Olsenella, Escherichia-Shigella, Candidatus_Saccharimonas, and fungal communities Mortierella, Lomentospora, Orpinomyces, and Saccharomyces. In addition, microorganisms that threaten health, such as Escherichia-Shigella, Mortierella, Lomentospora and Hydrogenoanaerobacterium, Corynebacterium_1, Trichosporon, and Coprinellus, were enriched in young and old yaks, respectively, although all yaks were healthy. The significant shifts in microflora composition and structure might reflect adaptation of gut microbiome, which is associated with physicochemical conditions changes and substrate availability in the gut across all development periods of yaks.

Study on the Formability of Aluminium Alloy Sheets at Room and Elevated Temperatures

2016 ◽  
Vol 877 ◽  
pp. 393-399
Author(s):  
Jia Zhou ◽  
Jun Ping Zhang ◽  
Ming Tu Ma
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Elevated Temperature ◽  
Aluminium Alloy ◽  
Aluminium Alloys ◽  
Elevated Temperatures ◽  
Hot Stamping ◽  
Natural Aging ◽  
Alloy Sheet ◽  
Aluminum Alloy Sheet

This paper presents the main achievements of a research project aimed at investigating the applicability of the hot stamping technology to non heat treatable aluminium alloys of the 5052 H32 and heat treatable aluminium alloys of the 6016 T4P after six months natural aging. The formability and mechanical properties of 5052 H32 and 6016 T4P aluminum alloy sheets after six months natural aging under different temperature conditions were studied, the processing characteristics and potential of the two aluminium alloy at room and elevated temperature were investigated. The results indicated that the 6016 aluminum alloy sheet exhibit better mechanical properties at room temperature. 5052 H32 aluminum alloy sheet shows better formability at elevated temperature, and it has higher potential to increase formability by raising the temperature.

scholarly journals Purification and Characterization of Asparaginase fromPhaseolus vulgarisSeeds

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Saleh A. Mohamed ◽  
Mohamed F. Elshal ◽  
Taha A. Kumosani ◽  
Alia M. Aldahlawi
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Lymphoblastic Leukemia ◽  
Potential Candidate ◽  
Purification And Characterization ◽  
Apparent Homogeneity ◽  
Wide Range ◽  
Optimum Ph ◽  
Glutaminase Activity ◽  
Low Activity

L-asparaginase from bacteria has been used in treatment of acute lymphoblastic leukemia. The aim of this study was to purify and characterize L-asparaginase fromPhaseolus vulgarisseeds instead of microbial sources. L-asparaginase was purified to apparent homogeneity. The enzyme has molecular mass of 79 kDa. The purified asparaginase had very low activity toward a number of asparagine and glutamine analogues. L-asparaginase was free from glutaminase activity. Kinetic parameters, Km andVmax of purified enzyme, were found to be 6.72 mM and 0.16 μM, respectively. The enzyme had optimum pH at 8.0. The enzyme showed high stability at alkaline pH (pH 7.5–9.0) when incubated for up to 24 h. L-asparaginase had the same temperature optimum and thermal stability at 37°C. K+was able to greatly enhance the activity of asparaginase by 150% compared with other metals tested. In conclusion, L-asparaginase showed no glutaminase activity and good stability over a wide range of physiological conditions, and thus it could be used as a potential candidate for treatment of acute lymphoblastic leukemia.

scholarly journals Characterization of a Viral Phosphoprotein Binding Site on the Surface of the Respiratory Syncytial Nucleoprotein

2012 ◽  
Vol 86 (16) ◽  
pp. 8375-8387 ◽  
Author(s):  
Marie Galloux ◽  
Bogdan Tarus ◽  
Ilfad Blazevic ◽  
Jenna Fix ◽  
Stéphane Duquerroy ◽  
...  
Keyword(s):  
Biochemical Characterization ◽  
Specific Interaction ◽  
Viral Rna ◽  
Site Directed Mutagenesis ◽  
Luciferase Reporter ◽  
Potential Candidate ◽  
Luciferase Reporter Gene ◽  
Interaction Domain ◽  
Rna Complex

The human respiratory syncytial virus (HRSV) genome is composed of a negative-sense single-stranded RNA that is tightly associated with the nucleoprotein (N). This ribonucleoprotein (RNP) complex is the template for replication and transcription by the viral RNA-dependent RNA polymerase. RNP recognition by the viral polymerase involves a specific interaction between the C-terminal domain of the phosphoprotein (P) (PCTD) and N. However, the P binding region on N remains to be identified. In this study, glutathioneS-transferase (GST) pulldown assays were used to identify the N-terminal core domain of HRSV N (NNTD) as a P binding domain. A biochemical characterization of the PCTDand molecular modeling of the NNTDallowed us to define four potential candidate pockets on N (pocket I [PI] to PIV) as hydrophobic sites surrounded by positively charged regions, which could constitute sites complementary to the PCTDinteraction domain. The role of selected amino acids in the recognition of the N-RNA complex by P was first screened for by site-directed mutagenesis using a polymerase activity assay, based on an HRSV minigenome containing a luciferase reporter gene. When changed to Ala, most of the residues of PI were found to be critical for viral RNA synthesis, with the R132A mutant having the strongest effect. These mutations also reduced or abolishedin vitroandin vivoP-N interactions, as determined by GST pulldown and immunoprecipitation experiments. The pocket formed by these residues is critical for P binding to the N-RNA complex, is specific for pneumovirus N proteins, and is clearly distinct from the P binding sites identified so far for other nonsegmented negative-strand viruses.

STRENGTHENING FEATURES AND AGING KINETICS OF HIGH-STRENGTH CAST ALUMINUM ALLOY AL4MS BASED ON Al–Si–Cu–Mg SYSTEM

2021 ◽  
pp. 24-34
Author(s):  
E.N. Kablov ◽  
◽  
E.V. Belov ◽  
A.V. Trapeznikov ◽  
A.A. Leonov ◽  
...  
Keyword(s):  
High Strength ◽  
Cast Aluminum Alloy ◽  
High Plasticity ◽  
Cast Aluminum ◽  
Second Stage ◽  
Low Temperature Aging ◽  
Aging Kinetics ◽  
Kinetics Of ◽  
Cold Box ◽  
Temperature Aging

Based on the conducted research, it has been found that quenching with hot isostatic pressure and step-by-step aging with consistently increasing temperatures of low-temperature aging (first stage) and high-temperature aging (second stage) provides high tensile strength for AL4MS copper silumin during cold box casting, increases the flow stress by 10%, and maintains high plasticity compared to the level of properties after single-stage aging.

Optical properties of silicene-dielectric interfaces from IR to far UV

2021 ◽  
pp. 2150235
Author(s):  
Yujun Hou ◽  
Chun Jiang
Keyword(s):  
Optical Properties ◽  
Single Layer ◽  
Normal Incidence ◽  
Complex Surface ◽  
Optical Characterization ◽  
Potential Candidate ◽  
Dielectric Interfaces ◽  
Uv Absorbers ◽  
Uv Range

Since the growth of single layer of Si has emerged, silicene became a potential candidate material to make up the disadvantage of graphene. In this paper, the complex surface conductivity is applied to characterize the properties of silicene and we investigate the optical characterization of silicene-dielectric interfaces from IR to far UV range. The silicene-Si and silicene-Ge interfaces along both parallel and perpendicular polarization directions of electromagnetic field with normal incidence are considered in this work. The optical properties of the silicene-dielectric systems proposed in this paper lay a foundation for the performance of complex silicene-based optoelectronic devices such as sensors, detectors, filters, UV absorbers and so on.

Sign in / Sign up

Export Citation Format

Share Document