Pan American Materials Congress: Materials for Transportation and Lightweighting: Composite Materials I and II (Consolidated)
Sponsored by: Third Pan American Materials Congress Organizing Committee
Program Organizers: Mary Wells, University of Waterloo; Rafael Colás, Universidad Autónoma de Nuevo León; Fernand Marquis, San Diego State University; Ramalinga Viswanathan Mangalaraja, University of Concepcion; Marta Lopez, University of Concepcion; Elvi Dalgaard, Pratt & Whitney Canada; Patricia Zambrano, Universidad Autonoma de Nuevo Leon

Thursday 8:30 AM
March 2, 2017
Room: Marina D
Location: Marriott Marquis Hotel

Session Chair: Ramalinga Viswanathan Mangalaraja, University of Concepcion

8:30 AM  
Nanodiamond: A Potential Reinforcement for Epoxy Composites: Ankita Bisht1; Pallavi Gupta1; Debrupa Lahiri1; 1Indian Institute of Technology Roorkee
    Nanodiamond (ND), a carbon-based nanoparticle having sp3 hybridization, has high hardness, excellent chemical stability and thermal conductivity and a typical average diameter of 2−10 nm. The outer surface of ND is originally covered by many functional groups such as hydroxyl, carboxyl, and ketone, which makes ND surface adapted for functionalisation without compromising its core properties. The spherical shape of ND (entanglement-free nanoparticle) with high interfacial area, as compared to platelet shape of graphene and tube like shape of CNT, and rich surface chemistry along with high mechanical properties makes it a promising candidate as reinforcement in structural composites.The present study reports the effect of ND as reinforcement to epoxy matrix, in terms of the mechanical (elastic modulus, hardness, fracture strength) and tribological properties of the composite. The potential of ND is being investigated here as a reinforcement for light weight high strength structural composite.

8:50 AM  
Tailored Carbide Powder Morphologies: Synthesis, Sintering, and Mechanisms of Formation: Tianqi Ren1; Olivia Graeve1; 1University of California, San Diego
    Transition metal carbides such as tantalum carbide (TaC), hafnium carbide (HfC), zirconium carbide (ZrC), and niobium carbide (NbC), are classified as ultra-high temperature ceramics (UHTCs) due to their extreme melting temperatures. Active research has focused on their applications as thermal protection coatings for hypersonic vehicles and rocket engine nozzles. We are exploring the possibility of controlling the particle morphology of carbide nanoparticles through dopant incorporation using a solvothermal method. We have observed promising cubic-faceted sharply-edged particles in TaC:15Y (15 at% Y), TaC:10Zr (10 at% Zr) and ZrC:10Ta (10 at% Ta) under scanning electron microscopy and transmission electron microscopy with sizes typically ranging from 20 to 100 nm. We believe that the dopants are effective in modifying the thermodynamic surface energies of the powders and the growth kinetics during synthesis. Sintering of the powders is achieved using spark plasma sintering to determine the effect of powder morphology during consolidation.

9:10 AM  
Nano-Additive Reinforcement of Thermoplastic Microballoon Epoxy Syntactic Foams: Kerrick Dando1; David Salem1; 1CAPE Lab, SDSM&T
    Syntactic foams comprised of glass microballoons have gained considerable attention over the past several years due to mechanical and thermal properties that are advantageous for use as a core material in naval and aerospace applications. Recently, advancements in the production of thermoplastic microballoon syntactic foams have allowed for an increase in microballoon volume fraction (up to 90 volume fraction), with corresponding lower densities but greatly reduced mechanical properties. In this work, carbon nanofibers and halloysite nanotubes are incorporated in thermoplastic microballoon-based syntactic foam to enhance its mechanical properties, and the effects of these two nanoscale reinforcement are compared. X-Ray micro computed tomography was employed to analyze the microstructure of the materials produced, and scanning electron microscopy was used to assess the dispersion of nano-additives within the resin. Through characterization of the tensile and compressive strength properties of these materials, it was observed that dramatic mechanical property enhancements can be engineered through additions of either nano-additive at specific loading levels.

9:30 AM  
Advantages of Hot Compression in the Manufacture of AlB4C Composites: Lucio Vazquez1; Dulce Velázquez1; Ángel Muñoz1; David Luna1; Gilberto Torres1; Elizabeth Garfias1; Manuel Vite1; 1Universidad Autonoma Metropolitana
    The aim of this work was to prove that preparation of AlB4C composites by hot compression at 350°C (HC) followed by sintering at 550°C would improve mechanical properties with respect to manufactured by cold compression (CC) followed by sintering at the same temperature, the later experiments were carried out in a previous work. Samples with aluminum matrix adding 0 %, 3 %, 5 % and 7 % adding B4C were prepared by powder metallurgy tchnique and tested. The mechanical properties were better using HC. Remarkably, resistance to compression was 3.5 times larger for HC. Vickers hardness, resistance to wearing and impact, as well as density were higher for HC. Scanning electron micrographs of CC specimens exhibit a cellular microstructure while HC ones display a smooth appearance. The better properties for the HC samples are explained due to an improved flow of material at higher temperatures of compression

9:50 AM  
Izod Impact Tests in Polyester Matrix Composites Reinforced with Fique Fabric: Artur Camposo Pereira1; Foluke Salgado de Assis1; Sergio Neves Monteiro1; Henry Colorado2; 1Instituto Militar de Engenharia; 2Universidad de Antioquia
    The fique fibers are studied worldwide as an alternative of synthetic fibers in composites. This study evaluated the impact resistance of this type of composite. Specimens were made with up to 30% in volume of fique fabric in an Izod normalized mold. The fique fabric was embedded with polyester resin and cured at room temperature for 24 hours. The specimens were tested in Izod impact pendulum and the fracture surfaces were examined by scanning electron microscopy (SEM). The impact resistance of composites increased linearly with the relative amount of fique fabric reinforcing the composite. This performance was associated with the difficulty of rupture imposed by the fique fabric as well as the type of cracks resulting from the interaction jute fiber / polyester matrix that corroborate the energy absorption at the impact test.

10:10 AM Break

10:30 AM  
An Improved Silicon Carbide Monofilament for the Reinforcement of Metal Matrix Composites: Michael Rix1; 1TISICS
    As part of a UK collaborative programme, TISICS have developed an improved 140 µm carbon coated silicon carbide monofilament employed in the reinforcement of metal matrix composites. The monofilament is fabricated in a single reactor using a high speed chemical vapour deposition process at a rate of 8m/min. Statistical analysis of monofilament properties over two years of production has demonstrated excellent reproducibility of the process. The monofilaments have an average tensile strength of 4.0±0.2 GPa with an average Weibull modulus of 50±10. Composites incorporating the monofilaments show similar low variability in yield and tensile strength with the latter exhibiting a mean value above 90% of the maximum theoretical strength predicted by the rule of mixtures. By varying the volume fraction and orientation of the monofilament reinforcement, composite properties can be tailored to fit design requirements. Examples are given of demonstrator components made for the European aerospace sector.

10:50 AM  
Effect of Al2O3 Volume Percentage on the Mechanical Properties and Strengthening Effect in Al Alloy Nano Composites Fabricated by Ultrasound Assisted Solidification Technique: Neeraj Srivastava1; G.P. Chaudhari1; 1Indian Institute of Technology Roorkee
    Al6061 alloy composites are fabricated by ultrasound solidification technique by varying the weight percentage (1, 3 and 5%) of Al2O3 nanoparticles. It is observed that high intensity ultrasound vibrations (~ 4.3 kW/cm2) to the melt resulted in well dispersion of Al2O3 particles in the Al6061 alloy matrix. The microstructural and mechanical properties of composites are investigated. The presence of nanoparticles are enhanced the mechanical properties of composites as compare to base alloy. A comparison is made between the experimental yield strengths of the nano composites and the theoretical yield strengths calculated by coefficients of thermal expansion mismatch, Hall-patch, load bearing effect and Orowan strengthening models.

11:10 AM  
Experimental and Density Functional Theory Studies of SmMn2O5 Mullite-type Oxide as NO Oxidation Catalyst: Sampreetha Thampy1; Yongping Zheng1; Sean Dillon1; Kui Tan1; Ka Xiong2; Yun-Ju Lee1; Yves Chabal1; Kyeongjae Cho3; Julia Hsu1; 1University of Texas at Dallas; 2Dongguan Innovative New Materials Co. Ltd.; 3University of Texas at Dallas and Dongguan Innovative New Materials Co. Ltd
    NO oxidation reaction is critical to mitigate toxic exhaust from diesel engines. A novel catalyst based on SmMn2O5 mullite was shown to exhibit 45% higher NO activity than platinum. Here we synthesize SmMn2O5 to understand the NO reaction pathways and catalytic activities on these materials. Infrared absorption and X-ray photoelectron spectroscopic studies show that nitrate dissociation on SmMn2O5 is faster compared to SmMnO3 perovskite. DFT suggests that the Mn3+O5 pyramids that link Mn4+O6 chains on mullite surface lower the energy barrier for this rate-limiting step, enabling mullite to regenerate its active sites. In contrast, strong binding of nitrate on isolated Mn3+ atoms of SmMnO3 leads to self-poisoning. Consequently, SmMn2O5 shows higher activity compared to SmMnO3. The insight gained through this study should pave way to design better NO oxidation catalysts based on Earth-abundant elements. This work is supported by Welch Foundation, Global Frontier Center, and Dongguan Innovative Research Program

11:30 AM  
Investigation on Mechanical Properties of Sic, Al2O3 and B4C Micro Particulates Reinforced in Aluminium Matrix Composite: Gopal Kumaresan1; K Kalaichelvan1; A Rajadurai1; 1Production Technology, MIT Campus, Anna University.
    For the past few decades, aluminium based hybrid composites have been widely used in many industries. Present trend of the cost reduction, durability, reliability, and weight reduction with excellent toughness, resistance to corrosion in the field of automobile, aircraft structure and naval structure has created major impact on the engineering industries. The ceramic reinforced composite materials have relevant properties to satisfy the above requirements. The purpose of this work aimed to investigate the effect of the addition of micro particles to aluminium on the mechanical properties of the composites. The micro composites containing different weight percentage of particles were fabricated using stir casting processes. The mechanical properties such as Tensile strength, Impact strength, hardness and micro structure are to be analyzed.

11:50 AM  
Nanocomposites Mechanical and Tribological Properties using Graphene Coated Ceramic Nanoparticles for Light Weight Applications: Ahmed Ghazaly1; Mohamed Shokeir1; Sandy El-Moghazi1; Ahmed Fathy1; Mohamed Emara2; Hanadi Salem1; 1American University in Cairo; 2Canadian College
    In the current work, Aluminum Alloy 2124-SiC/Graphene (SiC/G) nanocomposite is fabricated via high energy milling followed by uniaxial cold compaction at 525MPa, sintered at 450°C, and followed by hot extrusion at 4:1 extrusion ratio. SiC nanoparticles are encapsulated with nanographene layers forming G-coated SiC filler, used for the reinforcement of AA2124 matrices via milling. The processed nanocomposite combines the properties suitable for dry wear resistant and self-lubricating solids. It is anticipated that the formation of G-coated-ceramic-core nanoparticles decreases the agglomeration of SiC nanoparticles producing uniform dispersion of the G-coated-SiC reinforcement within the Aluminum matrices. Mechanical and tribological behavior of the processed SiC/G nanocomposites were characterized compared to the milled AA2124, AA2124-G and AA2124-SiC nanocomposites processed under similar milling conditions. FESEM and XRD are used for the investigation of the milled powders crystallite size, lattice strain, and phases as well as powder morphology.