MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)最新文献

{"title":"Fabrication and Characterization of PVA Based Cross-linked Film with Oxalic Acid","authors":"Madhur Dubey, N. Jain, Atul Kumar, Gaurang Deep, Mohd Sharib","doi":"10.2139/ssrn.3567161","DOIUrl":"https://doi.org/10.2139/ssrn.3567161","url":null,"abstract":"Different properties are point of attractive as per their field of application now days. A synthetic polymer such as PVA is one of the polymers which have recyclability and degradable properties. PVA is colorless, water soluble and have a unique property that it is not produced in polymerization reaction. PVA is produced by dissolving another polymer i.e. polyvinyl acetate (PVAc) in alcohol such as methanol and treating it with alkaline catalyst such as sodium hydroxide. In the present work main focus is to decrease water solubility along with improvement in mechanical properties. Oxalic acid (OA) was used as a crosslinker with PVA. Main parameter were concentration of oxalic acid (wt %), Curing Temperature (°C) and curing duration (Minutes). Water absorption test were performed to check water solubility, of PVA film crosslinked with oxalic acid. Mechanical characterization of films was done by tensile test which determines the UTS (ultimate tensile strength), % elongation and Young’s modulus. ANOVAs analysis was also performed to masseur the impact various factor on the properties of PVA film. It was observed in present work that water solubility decreases with increase in wt% of oxalic acid. Major factor was curing time duration. UTS of crosslinked film was increased by 142% as compared to neat PVA and maximum value of Young’s modulus was found 5857 MPa whereas neat PVA was only 1469MPA.","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130492276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Free Vibration and Damping Behaviour of Surface Treated Luffa/ Usp Composite Beams","authors":"K. G, S. Irullappasamy, M. Aslan","doi":"10.2139/ssrn.3654005","DOIUrl":"https://doi.org/10.2139/ssrn.3654005","url":null,"abstract":"The works expresses that the experiment work on the free vibration on the luffa cylidrica/ polyester composites. The influence of fiber loading and chemical treatment are analyzed. The composites beam structure are fabricated using the compression molding technique with optimum pressure of 17MPa. The NaOH treated and untreated fiber were utilized for production of composites. Specimen were prepared according to ASTM standard. By using the experiment nodal analysis, the natural frequencies and damping vales were found. The results shows that the increases in fiber loading initiated to enhance the mechanical properties of the composites but decrease the damping value. The chemical treatment also improves mechanical and damping behaviors of the composites. The 50% fiber loading produces the better tensile and flexural properties. Scanning electron microscope reveals the interfacial mechanism of the composites.","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"188 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122860047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Riddle of the Great Chilean Earthquake","authors":"S. Bychkov","doi":"10.2139/ssrn.3498662","DOIUrl":"https://doi.org/10.2139/ssrn.3498662","url":null,"abstract":"According to the theory of Elastic recoil of Mr. Reid, an earthquake occurs when tectonic plates slip relative to each other or along a fault. Plate movement is hindered by friction. When the stress reaches a critical point of ultimate rock strength, sudden displacement of the plate occurs [1]. Knowing the mass of the Nazca tectonic plate M = mg = 3.98 × 1021 × 9.8 kg and knowing the energy of the Great Chilean earthquake equal to A = 1.33 × 1020 J, we can easily calculate the magnitude of the plate displacement. According to the laws of mechanics, A = F × S, where, F - is the traction force when moving the load, S is the path traveled by the load. The traction force will be F = M × f, where f - is the friction coefficient, therefore, at A = 1.33 × 1020 J, M = 3.98 × 1022 kg, f = 0.1, the displacement of the Nazca plate at the time of the earthquake was: S = A / F × f = 1.33 ×1020 / 3.98 × 1022 × 0.1 = 0, 033 m.<br><br>That is, the earthquake energy was only enough to move the Nazca plate by only 3.3 centimeters!? Taking into account the compaction of soil and stones during plate displacement, closing of cracks, and the exit of liquids and gases, this figure can be safely halved. Given the volume of catastrophic destruction, expressed in the movement of the coastal strip 500 km long and 20-30 km wide, taking into account the destruction area of 2 × 105 km2 - a figure of 3.3 centimeters looks like an awkward mistake, which clearly demonstrates the inconsistency of theory and practice. It is hard to imagine that the movement of the Nazca plate by several centimeters could lead to such catastrophic consequences. What do you order to do with the received figure? Ignore? Find a plausible explanation? In any case, the question arises: what was the real displacement of the Nazca plate?","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127667847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Noninvasive High-Frequency Acoustic Microscopy for 3D Visualization and Estimation of Hydrolytic Degradation of Lactide and ε-Caprolactone Polymers","authors":"E. Morokov, V. Demina, N. Sedush, K. Kalinin, E. Khramtsova, P. Dmitryakov, A. Bakirov, T. Grigoriev, V. Levin, S. Chvalun","doi":"10.2139/ssrn.3493847","DOIUrl":"https://doi.org/10.2139/ssrn.3493847","url":null,"abstract":"Monitoring of kinetics of degradation process in polymers is one of the attractive possibilities of applying ultrasound techniques that provide non-destructive imaging of internal microstructure and measurements of elastics properties. In this work biodegradable polymers and copolymers based on L,L-lactide, D,L-lactide and ε-caprolactone were studied at different stages of hydrolysis at 37°C by high-frequency (100 and 200 MHz) ultrasound. Acoustic microscopy technique was developed to reveal changes in internal microstructure and bulk speed of sound in the polymer samples over a hydrolysis period of 25 weeks. Ultrasound imaging provided visualization of amorphous and crystalline phases, internal imperfections, packing density variation and other microstructure features. The acoustic images demonstrate nucleation, growth and changes of internal inhomogeneities in the polymers during the degradation accompanied by the decrease in molecular weight of the polymers. We associate changes of elastic properties (speed of longitudinal and transverse wave) with polymer crystallinity which varies over the hydrolysis process. The results of ultrasound investigations are supplemented by gel permeation chromatography, differential scanning calorimetry and wide-angle X-ray spectroscopy.","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132969050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimum Shear Stability at Intermittent-to-Smooth Transition of Plastic Flow in Metallic Glasses at Cryogenic Temperatures","authors":"Y.T. Wang, J. Dong, Y.H. Liu, H. Bai, W.H. Wang, B. Sun","doi":"10.2139/ssrn.3464579","DOIUrl":"https://doi.org/10.2139/ssrn.3464579","url":null,"abstract":"Abstract The runaway instability of shear bands leads to catastrophic failure of metallic glasses while the link between the shear banding process and the macroscopic plasticity in a quantitative manner in metallic glasses remains a major challenge.Through a series of compression tests at cryogenic temperatures, we found that the plasticity of the metallic glass can attain a maximum value at a critical temperature at which the transition from serrated flow to non-serrated flow occurs on a Zr-based metallic glass at cryogenic temperatures. The transition point corresponds to the lowest shear-band velocity and the most stable state of plastic shearing during deformation. The results provide an insight for understanding the temperature-dependent plasticity of metallic glasses from shear-band dynamics and may help to design the plasticity/ductility of metallic glasses at cryogenic temperatures.","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115180990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unusual Shear Induced Unconventional {1011} Twinning in Mg","authors":"Shafiev Ma, Xiaozhi Tang, Qun Zu, Ya-Fang Guo","doi":"10.2139/ssrn.3476419","DOIUrl":"https://doi.org/10.2139/ssrn.3476419","url":null,"abstract":"Conventional (1011) twinning in hexagonal metals has the twin plane K1 = (1011) and the corresponding twinning direction η1=[1012]. Twinning shear is generally accomplished through the gliding of two-layer and/or four-layer twinning dislocations (TDs) along η1 associated with atomic shuffles. Using molecular dynamics simulations, we reveal that an unusual shear along -η1 associated with atomic shuffles on the twin plane K1 is resulted by gliding of a one-layer TD. Correspondingly, an unconventional {1011} twinning occurs through successive gliding of one-layer TDs. Such a twinning mechanism is found to be correlated to high stress/strain concentration, such as at crack tip.","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115232575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanically Robust Soft Bioelectronics: Towards Conductive Elastomers with a Low Percolation Threshold","authors":"A. Novikov, J. Goding, Christopher Chapman, Estelle A. Cuttaz, R. Green","doi":"10.2139/ssrn.3477576","DOIUrl":"https://doi.org/10.2139/ssrn.3477576","url":null,"abstract":"Conductive polymer-elastomer composites have been proposed as an alternative to the metals conventionally used for bioelectronic devices. Being softer and more stretchable than metals such as platinum and gold, they can mitigate the adverse effects associated with mechanical mismatch and fatigue failure. Such composites are conventionally made by embedding conductive polymer (CP) particles inside an elastomeric matrix. However, to achieve such a structure, a high CP loading that reaches a percolation threshold is required. High percolation thresholds lead to the degradation of mechanical properties. This study presents an alternate approach designed to reduce CP content while maintaining conductivity through the matrix. A PEDOT:PSS composite was produced by filling a CP aerogel with polydimethylsiloxane (PDMS). This approach successfully formed a robust and conducting material, with only 1.8wt% CP. However, the composite displayed plastic deformation behaviour limiting electrical performance under strain. Potential improvements lie within modification of the PEDOT:PSS/PDMS interface.","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127913997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Discovery of a Wide Variety of Linear Complexions in Face Centered Cubic Alloys","authors":"V. Turlo, T. Rupert","doi":"10.2139/ssrn.3436419","DOIUrl":"https://doi.org/10.2139/ssrn.3436419","url":null,"abstract":"Linear complexions are defect states that have been recently discovered along dislocations in body centered cubic Fe-based alloys. In this work, we use atomistic simulations to extend this concept and explore segregation-driven structural transitions at dislocations in face centered cubic alloys. We discovered a variety of stable, nanoscale-size structural and chemical states, which are confined near dislocations and can be classified as linear complexions. Depending on the alloy system and thermodynamic conditions, such new states can preserve, partially modify, or completely replace the original defects they were born at. By considering different temperatures and compositions, we construct linear complexion diagrams that are similar to bulk phase diagrams, defining the important conditions for complexion formation while also specifying an expected complexion size and type. Several notable new complexion types were discovered here: (1) nanoparticle arrays comprised of L12 phases in Ni-Fe, Ni-Al, and Al-Zr, (2) replacement of stacking faults with layered complexions comprised of (111) planes from the Cu5Zr intermetallic phase in Cu-Zr, (3) platelet arrays comprised of two-dimensional Guinier-Preston zones in Al-Cu, and finally (4) coexistence of multiple linear complexions containing both Guinier-Preston zones and L12 phases in ternary Al-Cu-Zr. All of these new complexion states are expected to alter material properties and affect the stability of the dislocations themselves, offering a unique opportunity for future materials design.","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132614540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Core‒Rim Structures and Hierarchical Phase Relationship for Hot-Pressed ZrB 2‒SiC‒MC (M=Nb, Hf, Ta, W) Ceramics","authors":"Dong-Li Hu, H. Gu, J. Zou, Q. Zheng, Guo‐Jun Zhang","doi":"10.2139/ssrn.3358890","DOIUrl":"https://doi.org/10.2139/ssrn.3358890","url":null,"abstract":"Core‒rim structure emerges as a common microstructural feature of hot-pressed ZrB2‒SiC‒MC (M=Nb, Hf, Ta and W) ceramics. A combination of X-ray diffraction and microscopic analyses reveal that it originates from the re-distribution of transition-metals into their bi-solubility in the primary phase, hence turning the core‒rim structures into an intra-phase relationship. Solution‒reprecipitation process rationalizes their formation via a transient liquid-phase of Zr‒M‒B‒C‒(O). It dictates the special transformation process by enabling an exchange of metal with cores to reach the lower solubility and a transition to grow rims into higher solubility, driven by an over-saturation of boron in the liquid. A third and even higher solubility in the minor ZrC phase finalizes the liquid-phase sintering process, leading to hierarchical phase relationship. We propose further a scheme of g-point to syndicate the bi-solubility as solidus and liquidus limits of metal in ZrB2 phase, hence to schematize the coordinated evolution of multiphase microstructures. The core/rim boundaries can strengthen the ceramics by storing and re-distributing strain energy within the grains, which leaves the microstructure‒property relationship to renew and further optimize for UHTC.","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126759665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Многослойная тканеинженерная конструкция на основе биодеградируемых и биосовместимых материалов для восстановления поврежденных желчных путей (Multilayered Tissue-engineered Construct Based on Biodegradable and Biocompatible Materials for Injured Biliary Tract Repair)","authors":"Ilya Klabukov","doi":"10.2139/ssrn.2900882","DOIUrl":"https://doi.org/10.2139/ssrn.2900882","url":null,"abstract":"Design of bioengineered organs is still complicated due to the lack of understanding of biological mechanisms that stimulate physiologically relevant conditions and induce relevant cellular media. Systematic review identified qualitative and quantitative requirements for tissue-engineered construct of the common bile duct. Tissue-specific approach was used to select materials, biologics, and cells for creation of physiologically relevant construct for injured biliary tract repair. Samples of fibrous scaffolds from PCL, PGLA, PLCL, and cellulose diacetate were created by electrospinning method and evaluated with MTT assay for cytotoxicity assessment. Mechanical properties of human bile duct sample and fibrous scaffolds were evaluated for Young's modulus and for percentage of elongation. Mechanical properties of fibrous materials were evaluated in vitro during degradation and erosion in various media. Fibrous PCL-scaffolds were formed by emulsion electrospinning with incorporation of following biomolecules: Neovasculgen gene-therapy drug (VEGF165 plasmid), EGF and GFP. The fluorescent microscopy of fibers confirmed volume modification by biomolecules. ELISA-test confirmed prolonged exit of EGF biomolecules from PCL-scaffold in vitro. Implantation of Neovasculgen-modified PCL-scaffold in rats showed vascular density increase in the implantation zone. Experimental swine model of iatrogenic bile duct injury was created and follow-up implantation of tubular fibrous PCL-scaffold in porcine bile duct showed a tissue-specific physiological biocompatibility of fibrous PCL. Fibrous three-layered scaffolds from PCL and PLCL/PLGA were obtained by electrospinning method and were tested for mechanical properties. The sample of three-layered scaffold from modified fibrous PCL and PLGA with incorporation of EGF and Neovasculgen was two-side seeded with bone marrow-derived mesenchymal stem cells and bile duct epithelial cells to obtain the tissue-engineered construct.","PeriodicalId":442517,"journal":{"name":"MatSciRN: Other Mechanical Properties & Deformation of Materials (Topic)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127100693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}