Pan American Materials Congress: Materials for Transportation and Lightweighting: Poster Session
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

Tuesday 5:30 PM
February 28, 2017
Room: Poster Area
Location: Marriott Marquis Hotel

PAN-28: Analysis of Coir Fiber Porosity: Fernanda da Luz1; Sérgio Monteiro1; 1Military Institute of Engineering, IME
    Lignocellulosic natural fibers exhibit high dispersion in mechanical properties values due to their heterogeneity. Recent studies have shown that the variation of these properties depends on the diameter of the fiber. A possible explanation for the tendency of low mechanical properties with large diameter is the high probability of defects into the fiber. However, no study has yet investigated the relation between the diameter and defects of natural fibers. Hence, in the present work the total porosity of coir fiber was quantified. The close and open porosity as well as the density of the fiber, were correlated with the diameter of each analyzed fiber. Mercury porosimetry was conducted to obtain not only values of porosity but also its pore size distribution for each diameter. Results made it possible a more detailed knowledge of the porous structure of the fiber.

PAN-29: Ballistic Performance in Multilayer Armor with Epoxy Composite Reinforced with Malva Fibers: Lucio Nascimento1; Luis Henrique Leme Louro1; Sérgio Neves Monteiro1; Alaelson Vieira Gomes1; Édio Pereira Lima Júnior1; Rubens Marçal1; Fábio Braga1; 1Instituto Militar de Engenharia
    A multi-layer armouring system (MAS) is commonly formed by three layers. The initial layer is normally composed by a ceramic with high compressive strength, which absorbs most of the kinetic projectile energy. The subsequent composite layer was formed by epoxy matrix reinforced with natural malva fibers (Urena lobata, Linn), in order to absorb part of the kinetic energy, and to retain ceramic and projectile shrapnel. A third layer formed by aluminum alloy, was included as a penetration restrictor for bullet and fragments by plastic deformation. The ballistic efficiency was evaluated by estimating the speed limit (VL), which depends on the energy absorbed by each armouring layer upon impact of the 7.62mm projectile. The results showed a great potential by epoxy composites reinforced with malva fibers as compared to other natural fibers and materials traditionally used in personal protection, such as Kevlar® aramid.

PAN-30: Curaua Non-woven Fabric Composite for Ceramic Multilayered Armors: A Lightweight, Natural, and Low Cost Alternative for KevlarTM: Fábio Braga1; Augusto Cabral1; Édio Lima Jr.1; Sergio Monteiro1; Foluke de Assis1; 1Military Institute of Engineering (IME)
    Advanced ceramics have been extensively applied for ballistic protection, when high levels of protection and low weight are demanded. However, their spalling characteristics require suitable backing materials to collect the fragments generated on the impact. Synthetic fiber laminates, as KevlarTM and DyneemaTM, are currently the most used solutions, despite their high cost and non-sustainable conditions. Therefore, several materials are being studied to replace the synthetic fiber laminates as second layer, including natural fiber composites, which are light, low cost and sustainable materials. Among these, Amazon curaua fiber composites are promising, due to its known high strength and high modulus. In the present work, novel curaua non-woven fabrics polymer composites have been investigated as part of the ceramic armor system. Ballistic tests were performed following NIJ 0101.06 armor standard. The results showed that these composites are promising alternatives to the synthetic fiber laminates as ceramic backing materials.

PAN-31: Effect of Porosity and Bimodal Microstructure of Ti-based Alloy Foams Consolidated by Hot Pressing: Christopher Salvo1; Claudio Aguilar2; Sheila Lascano2; R.V. Mangalaraja1; 1University of Concepcion; 2Universidad Técnica Federico Santa Maria
    Nowadays, Ti based alloys are widely used as bio-implant materials because their excellent properties, but their Young`s modulus values are higher than the human bones. This work reports the synthesis of Ti-30Nb-13Ta-2Mn foams using NaCl as space holder (0, 20 and 30% vol. added) and bimodal microstructure. Hot pressing was used to consolidate the green samples under 30 MPa at 780C for 30 minutes. Further, the foams were characterized by optical microscopy, SEM and XRD. The elastic modulus of the foam was measured as 15 GPa, and the values were almost equal to the values predicted using theoretical models. Foams showed non-homogeneous distribution of macropores and suitable characteristics to promote cell adhesion and bone growth. The sizes of macropores produced by the space holder were between 200 and 400 um and deformation of NaCl particles was clearly visible. All the foams with bimodal structure showed a high percentage of porosity.

PAN-32: Heat Treatment of Reaction Bonded Composites: Evgeni Ionash1; Helen Dilman1; Shmulik Hayun1; Nachum Frage1; 1Ben Gurion University of Negev
    Under the conditions of the reaction bonded composites fabrication only limited amount of Si is involved in the interaction and the fraction of new formed SiC is also limited. We suggest to apply an additional thermal treatment of the infiltrated composites within the liquid soda-lime glass at 1400°C, when Si evaporation is completely avoided. We tested the suggested approach using SiC + B4C mixture with 40%wt. of boron carbide. The relative green density of compact was about 65% and the hardness value of the infiltrated composite is about 1300HV. After 24 hours of heat treatment in glass at 1400°C the hardness increased up to 1500HV. SEM analysis of the heat treated specimens confirms that the fraction of SiC increased, while the fraction of residual Si decreased. The suggested conditions of heat treatments may be a promising for hardness increasing and improving a ballistic efficient of reaction bonded SiC composites.

PAN-33: Influence of Carbon Nanotube and Graphene on Mechanical and Damping Characteristics of Epoxy Matrix Composite- A Comparative Analysis: Ankita Bisht1; Pallavi Gupta1; Debrupa Lahiri1; 1Indian Institute of Technology Roorkee
    Epoxy is widely used as matrix in advanced high performance polymer composites due to its mechanical properties, compatibility with most reinforcement, chemical resistance, low cost etc. But, its major drawbacks are low fracture toughness and damping properties, which can be improved by adding reinforcement phase. Carbon nanotube and graphene are most favourable choice as reinforcement, due to their chemical compatibility, as well as, exceptionally impressive mechanical and thermal properties. Present study reports a comparative analysis between carbon nanotube and graphene as reinforcement to epoxy. The behavior of these two nanofillers and their interaction with polymer matrix can be quite different, considering their vastly different morphology, leading to different mechanical and thermal properties. Tensile test, fracture analysis and DMA studies are carried out to quantify the difference in improvement in properties with different amounts and type of reinforcement. Further analysis is carried out to understand the differential mechanisms acting behind.

PAN-34: Izod Impact Tests in Polyester Matrix Composites Reinforced with Jute Fabric: Foluke de Assis1; Sergio Monteiro1; Artur Pereira1; Fábio Braga1; 1Military Institute of Engineering
    Jute fibers are among the lignocellulosic fibers with greater potential for use as fabric reinforcing polymer composites. This study evaluated the impact resistance of this type of composite. Specimens were made with up to 30% in volume of jute fabric in an Izod normalized mold. The jute 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 jute fabric reinforcing the composite. This performance was associated with the difficulty of rupture imposed by the jute 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..

PAN-35: Processing and Characterization of the Electromagnetic Wave Absorption Potential of Glass Fiberreinforced Thermoset Polymer Matrix Composites: Tugce Altuntop1; 1Middle East Technical University
    The purpose of this study is to examine the processing and to observe the electromagnetic behaviors of glass woven fiber thermoset polymer matrix composites. Fabrication of metallic nanowire coating surface modified glass fiber reinforced thermoset polymer matrix composites was obtained by using epoxy as thermoset polymer matrix and glass fiber as reinforcement. Electromagnetic wave absorption behavior and electromagnetic interference shielding potential of the fabricated composites in 18-40 GHz frequency was determined using free space method. Microstructural investigation of the composites has been conducted through scanning electron microscope examinations. Moreover, the effect of surface coating on the glass fibers on the mechanical properties of the glass fiber reinforced thermoset polymer matrix composites has been observed by the application of three point bendind tests.

PAN-36: Tensile and Impact Properties of Two Fiber Configurations for Curaua Reinforced Composites: Fábio Braga1; Noan Simonassi1; Augusto Cabral1; Sergio Monteiro1; Foluke de Assis1; 1Military Institute of Engineering (IME)
    Natural fibers have been extensively investigated in the past decades, due to their good properties, lightweight, low cost and renewable nature. From the ananas erectifolius plant, high strength and high modulus curaua fibers can be obtained. Their remarkable properties make them adequate to several high performance applications. In the present work, tensile and impact properties of two fiber configurations for curaua reinforced composites were investigated: a non-woven fiber fabric (NWFF) and high percentage continuous and aligned fiber (HPCAF) composites, using epoxy and polyester as polymeric matrix, respectively. The results showed that the fabric configuration does not effectively reinforce the polymer on tensile load, in spite of promoting significant improvement on the impact properties of the composite. The latter configuration results in both high strength and tough composites, however, its ability to resist to impacts depends on the direction of load.

PAN-37: The Effect of Ni on the Structural, Hardness and Magnetic Properties of Cu90-xCo10Nix – 7.5% SmCo5 Composite Alloys Prepared by Powder Metallurgy Route: Marta Lopez1; Mangalaraja Ramalinga Viswanathan1; Christopher Salvo1; Felipe Sanhueza1; Jose Jiménez2; 1University of Concepcion; 2Centro Nacional de Investigaciones Metalúrgicas, CENIM-CSIC
    Copper composite alloys (Cu90-XCo10NiX-7.5SmCo5, with Nix = 0, 20wt%) were obtained by the powder metallurgy route, by milling Cu90-XCo10NiX and Cu90-XCo10NiX-7.5%SmCo5 in two steps. The X–ray diffraction patterns of both milled powders showed only Cu diffraction peaks which indicated that Co, Ni and SmCo5 were incorporated into the copper crystal lattice to form Cu(Co,Ni) and Cu(Co, Ni, Sm) solid solutions. The final consolidation of the Cu90-xCo10Nix – 7.5% SmCo5 alloy powders by hot pressing under argon atmosphere showed the precipitation of dark micron-nanometric particles inside the copper matrix and a few bright particles, identified as Co(Ni) and Co5O12Sm3 ferromagnetic phases respectively, from the Rietveld refinement of the XRD patters and the electron probe micro analysis. Both particles have a decisive influence on the magnetic properties of Cu90-xCo10Ni20wt%)–SmCo5 alloy due to ferromagnetic behavior mainly of Co(Ni) particles, registering coercive field values between 13607.7 and 26419.6 A/m.

PAN-38: Thermo-mechanical Properties of Copolymer/Clay Nanocomposites: A Comparative Study of Production Method by In-situ and Solution Mixture: Oscar Hernández Guerrero1; Mireya Hernández Vargas2; Rubén Castillo Pérez2; Bernardo Campillo Illanes2; 1UAEM; 2Universidad Nacional Autónoma de México
    The field of polymer/clay nanocomposites is a new route for preparing polymers with enhanced properties like increased modulus, thermal stability, better barrier properties, chemical resistance and electrical conductivity. In this work, nanoclay montmorillonite (MMT) was incorporated as reinforcement to a copolymer matrix, containing 0, 5 and 10 wt% nanoclay. The nanocomposites were prepared by two different processes via in-situ (MMT-IN) and solution mixing (MMT-B). These nanocomposites show an increase in their glass transition temperature, Tg, studied by differential scanning calorimetry (DSC), and also an increment by an order of magnitude in the young's modulus for both series. On the other hand, the study of thermogravimetric analysis (TGA) for the two series IN and B with addition of montmorillonite clay nanoparticles showed a decreasing behavior in thermal decomposition temperatures, Tdec, relative to the neat copolymer matrix.

PAN-39: Thermo−Mechanical Behavior of Nanostructure Polyacrylic Polymer Based on Al2 O3 and Bentonite Nanoparticles: Ruben Castillo-Pérez1; Mireya Hernández-Vargas1; Oscar Hernández-Guerrero2; Bernardo Campillo-Illanes1; Osvaldo Flores-Cedillo1; 1Universidad Nacional Autónoma de México; 2Universidad Autónoma del Estado de Morelos
    This work focuses on the influence of inorganic spheres-particles such as Al2 O3 and platelets, such as Bentonite clay, on the thermo-mechanical properties of the acrylic polymer. The nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis, uniaxial tension, nanoindentation and scanning electron microscopy (SEM). Films drawn from the latex exhibited excellent optical transparency and no evidence of aggregation was detected by SEM and X-ray energy dispersive spectroscopy (EDS). The analysis of the thermal and mechanical properties in the presence of platelets nanoparticles (Bentonite), showed an increase in the glass transition temperature (Tg), decomposition temperatures (Tdec), the Young's modulus and their hardness. On the other hand, in the presence of spherical nanoparticles (Al2 O3), the thermal (Tg and Tdec) and mechanical properties decrease, due to the morphology, dimension (e.g., aspect ratio) and degree of dispersion of the nanofillers in the polymer matrix.

PAN-40: Thermo−Mechanical Properties of Waterborne Acrylate Hybrid Nanocomposites: Mireya Lizbeth Hernandez-Vargas1; Rubén Castillo-Perez1; Oscar Hernández-Guerrero2; Bernardo Fabián Campillo-Illanes1; Osvaldo Flores-Cedillo1; 1Universidad Nacional Autónoma de México; 2Universidad Autónoma del Estado de Morelos
    Waterborne acrylate hybrid nanocomposites containing 1 wt% nanoparticles were synthesized by in situ polymerization using SiO2 and Fe2O3 nanoparticles. The synthesized latex hybrids were characterized by thermogravimetric analysis, uniaxial tension, nano−indentation and scanning electron microscopy (SEM). Films drawn from the latex exhibited excellent optical transparency and no evidence of aggregation was detected by SEM and X−ray energy dispersive spectroscopy (EDS) analysis confirmed the presence of silica and iron throughout the films. The thermal properties showed a decrease of the glass transition temperature in the presence of Fe2O3 nanoparticles as demonstrated by the dynamic mechanical analysis. The nano−SiO2 induced significantly higher thermal stability, as decomposition temperatures of the nanocomposites increases by as much as 40°C relative to the neat acrylic. On the other hand, the Young’s modulus and hardness of the nanocomposites films decrease about 40% and 35%, denoting a modification of macromolecular dynamic by the SiO2 and Fe2O3 nanoparticles, respectively.

PAN-41: Ultra High Molecular Weight Polyethylene Reinforced with Ceramics Nanoparticles: Édio Lima Júnior1; Sergio Monteiro1; Ricardo Weber1; Alaelson Vieira1; 1Military Institute of Engineering
    Efficient materials for ballistic protection with low weight are essential in the actual global stage of armed conflicts. Among the possibilities of low density materials, the ultra high molecular weight polyethylene (UHMWPE) stands out in the currently used materials. In the present work, in order to improve the mechanical properties and obtain better results in ballistic tests, ceramics nanoparticles were added in to UHMWPE matrix and the corresponding composite was analyzed by mechanical and ballistic tests. The results were compared with UHMWPE processed similarly without nanoparticles charges. Scanning electronic microscopy (SEM) revealed the mechanism responsible for improving the ballistic performance.