Local Mechanical Characterization of Human Teeth by Instrumented Indentation

2010 ◽  
Vol 89-91 ◽  
pp. 751-756 ◽  
Author(s):  
Ilaria Cappelloni ◽  
Paolo Deodati ◽  
Roberto Montanari ◽  
Andrea Moriani
Keyword(s):  
Mechanical Characteristics ◽  
Mechanical Characterization ◽  
Damping Factor ◽  
Good Resolution ◽  
Instrumented Indentation ◽  
Mechanical Spectroscopy ◽  
Human Teeth ◽  
Indentation Tests ◽  
Cylindrical Punch

The mechanical characteristics of dentine have been investigated on local scale by micro-hardness and instrumented indentation tests. FIMEC, an indentation technique employing a cylindrical punch, permitted measurements of elastic modulus, yield stress, stress-relaxation and creep. The punch diameter (Φ = 0.5 mm) is much larger than the tubule size thus data are not so largely scattered as in micro- and nano-indentation tests but, at the same time, is small enough to guarantee a good resolution in mapping the mechanical properties in different tooth positions. The results are in agreement with literature data obtained by means of various experimental techniques. Furthermore, through tests of mechanical spectroscopy carried out on bar-shaped samples (13 mm x 4 mm x 0.8 mm) the dynamic modulus and the damping factor Q-1 have been measured.

Characterization of Medium Density Particleborads Using Agricultural Residues

2015 ◽  
Vol 1088 ◽  
pp. 656-659
Author(s):  
Ivaldo D. Valarelli ◽  
Rosane A.G. Battistelle ◽  
Barbara Stolte Bezerra ◽  
Luiz A. Melgaço N. Branco ◽  
Eduardo Chahud ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Castor Oil ◽  
Mechanical Characteristics ◽  
Mechanical Characterization ◽  
Raw Materials ◽  
Construction Materials ◽  
Agricultural Residues ◽  
Medium Density ◽  
Polyurethane Resin

In recent years the production of products derived from wood and bamboo are increasing, due to the search for a more rational exploitation of these raw materials. Amongst these products, the particleboards production combine sustainability and rationality in the use of these materials. In this context, this work has the objective to study the application of alternative raw materials in the manufacture of Medium Density Particleboards (MDP), using residues from industrial processimg of coffee and bamboo. MDP had been produced with particles of giganteus bamboo of the Dendrocalamus species and particle of coffee rind in the intermediate layer of the particleboard, bonded with polyurethane resin based on castor oil. The physical and mechanical characterization was carried out accordingly to NBR 14810-3 (2006). The physical properties evaluated were: of water absorption for 2h and 24h; thickness swallowing for 2h and 24h; density, humidity content. The mechanical properties evaluated were: Tensile strength, static bending (MOR and MOE). The results were compared with NBR 14810-2 (2006) and also with the ANSI A208-1 (1993). The physical performance of these particleboards was below the values recommend by the Brazilian norm. Also the mechanical characteristics are not improve, demonstrating that the inclusion of coffee rind did not benefit the physical characteristics and nor the mechanical ones. However it can be used as construction materials for partitions and ceiling panels.

Inverse Mechanical Characterization of Tissue Engineered Heart Valves

2008 ◽  
Author(s):  
Martijn A. J. Cox ◽  
Jeroen Kortsmit ◽  
Niels J. B. Driessen ◽  
Carlijn V. C. Bouten ◽  
Frank P. T. Baaijens
Keyword(s):  
Heart Valves ◽  
Soft Tissues ◽  
Mechanical Characterization ◽  
Tensile Tests ◽  
Material Behavior ◽  
Uniaxial Tensile ◽  
Mechanical Conditioning ◽  
Indentation Tests ◽  
Tissue Engineered Heart Valves

Over the last few years, research interest in tissue engineering as an alternative for current treatment and replacement strategies for cardiovascular and heart valve diseases has significantly increased. In vitro mechanical conditioning is an essential tool for engineering strong implantable tissues [1]. Detailed knowledge of the mechanical properties of the native tissue as well as the properties of the developing engineered constructs is vital for a better understanding and control of the mechanical conditioning process. The nonlinear and anisotropic behavior of soft tissues puts high demands on their mechanical characterization. Current standards in mechanical testing of soft tissues include (multiaxial) tensile testing and indentation tests. Uniaxial tensile tests do not provide sufficient information for characterizing the full anisotropic material behavior, while biaxial tensile tests are difficult to perform, and boundary effects limit the test region to a small central portion of the tissue. In addition, characterization of the local tissue properties from a tensile test is non-trivial. Indentation tests may be used to overcome some of these limitations. Indentation tests are easy to perform and when indenter size is small relative to the tissue dimensions, local characterization is possible. We have demonstrated that by recording deformation gradients and indentation force during a spherical indentation test the anisotropic mechanical behavior of engineered cardiovascular constructs can be characterized [2]. In the current study this combined numerical-experimental approach is used on Tissue Engineered Heart Valves (TEHV).

Growth Kinetics and Mechanical Characterization of a Hard Boron Coating on a Tool Steel

2017 ◽  
Vol 380 ◽  
pp. 29-34 ◽  
Author(s):  
D. Sánchez Huerta ◽  
N. López Perrusquia ◽  
I. Hilerio Cruz ◽  
M.A. Doñu Ruiz ◽  
E.D. García Bustos ◽  
...  
Keyword(s):  
Activation Energy ◽  
Mechanical Characteristics ◽  
Mechanical Characterization ◽  
Chemical Elements ◽  
Thermochemical Treatment ◽  
X Ray Diffraction ◽  
X Ray ◽  
Optimal Classification

The mechanical characteristics are determined to a FeB/Fe2B coating applied in AISI L6 steel tool and blades make to cut paper. The thermochemical treatment was applied at temperatures of 1173, 1223 and 1273 K with permanence time of 0.5, 2 and 3 h for each temperature. The diffusion coefficient and activation energy for each phase is obtained for this boron coating on an AISI L6 steel. HRC test were made to establish the type of adherence (qualitative) and comparing with the VDI 3198 standard and the results were obtaining optimal classification of HF1-HF2 in condition for 3h of the three temperatures. The result by nanoidentation show hardness of 1000 - 2000 HV as well as the Young's modulus for each present phase of the coating. Through micrographs (SEM) are showing thicknesses up to 79.52 ± 18.82 μm for FeB and 97.80 ± 20.01μm for Fe2B, a morphology sawn ́s type is evidence. Through EDS and x-ray diffraction are used to show the chemical elements formed.

Mechanical characterization of brittle materials using instrumented indentation with Knoop indenter

2017 ◽  
Vol 108 ◽  
pp. 58-67 ◽  
Author(s):  
Ghailen BEN Ghorbal ◽  
Arnaud Tricoteaux ◽  
Anthony Thuault ◽  
Ghislain Louis ◽  
Didier Chicot
Keyword(s):  
Mechanical Characterization ◽  
Brittle Materials ◽  
Instrumented Indentation ◽  
Knoop Indenter

scholarly journals Preparation, Thermal, and Mechanical Characterization of UV-Cured Polymer Biocomposites with Lignin

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1159
Author(s):  
Marta Goliszek ◽  
Beata Podkościelna ◽  
Tomasz Klepka ◽  
Olena Sevastyanova
Keyword(s):  
Mechanical Characteristics ◽  
Mechanical Characterization ◽  
Polymer Network ◽  
Positive Influence ◽  
Hydroxyl Groups ◽  
Reactive Diluent ◽  
Carbonyl Groups ◽  
Waste Generation ◽  
Acrylate Monomers

The preparation and the thermal and mechanical characteristics of lignin-containing polymer biocomposites were studied. Bisphenol A glycerolate (1 glycerol/phenol) diacrylate (BPA.GDA) was used as the main monomer, and butyl acrylate (BA), 2-ethylhexyl acrylate (EHA) or styrene (St) was used as the reactive diluent. Unmodified lignin (L) or lignin modified with methacryloyl chloride (L-M) was applied as an ecofriendly component. The influences of the lignin, its modification, and of the type of reactive diluent on the properties of the composites were investigated. In the biocomposites with unmodified lignin, the lignin mainly acted as a filler, and it seemed that interactions occurred between the hydroxyl groups of the lignin and the carbonyl groups of the acrylates. When methacrylated lignin was applied, it seemed to take part in the creation of a polymer network. When styrene was added as a reactive diluent, the biocomposites had a more homogeneous structure, and their thermal resistance was higher than those with acrylate monomers. The use of lignin and its methacrylic derivative as a component in polymer composites promotes sustainability in the plastics industry and can have a positive influence on environmental problems related to waste generation.

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