Mechanical properties analysis

R.J. Ding and P.A. Olgetz, Mechanical Property Analysis in the Retracted Pin-... 

COMPUTER AUTOMATION OF THE DYNAMIC MECHANICAL ANALYZER AND ITS APPLICATION TO CURE KINETICS STUDIES AND DYNAMIC MECHANICAL PROPERTY ANALYSIS OF ORGANIC COATINGS... 

M. E. Koehler, A. F. Kah, C. M. Neag, T. F. Niemann, F. B. Malihi, and T. Provder, "Computer Automation Of The Dynamic Mechanical Analyzer And Its Application To Cure Kinetics Studies And Dynamic Mechanical Property Analysis Of Organic Coatings", this volume. 

CNT-polymer composites are commonly produced in the form of films for mechanical property analysis. The thicknesses of these films range from a few millimeters to... 

Thongruang, W., Spontak, R.J., and Balik, C.M. (2002) Correlated electrical conductivity and mechanical property analysis of high-density polyethylene filled with graphite and carbon fiber. Polymer 43, 2279-2286. 

Siegel R W 1996 Gas phase synthesis and mechanical properties of nanomaterials Analysis 24 M10... 

The modeling of solids as a continuum with a given shear strength, and the like is often used for predicting mechanical properties. These are modeled using hnite element or hnite difference techniques. This type of modeling is usually employed by engineers for structural analysis. It will not be discussed further here. 

Polypropylene molecules repeatedly fold upon themselves to form lamellae, the sizes of which ate a function of the crystallisa tion conditions. Higher degrees of order are obtained upon formation of crystalline aggregates, or spheruHtes. The presence of a central crystallisation nucleus from which the lamellae radiate is clearly evident in these stmctures. Observations using cross-polarized light illustrates the characteristic Maltese cross model (Fig. 2b). The optical and mechanical properties ate a function of the size and number of spheruHtes and can be modified by nucleating agents. Crystallinity can also be inferred from thermal analysis (28) and density measurements (29). 

Dynamic mechanical analysis provides a useful technique to study the cure kinetics and high temperature mechanical properties of phenoHc resins. The volatile components of the resin do not affect the scan or limit the temperature range of the experiment. However, uncured samples must be... 

The molecular weight and the distribution of multiple molecular weights normally found within a commercial polymer influence both the processibiUty of the material and its mechanical properties. Eor a few well-defined homopolymers, an analysis of composition and molecular weight is sufficient to define the likely mechanical properties of the polymer. 

The dynamic mechanical properties of VDC—VC copolymers have been studied in detail. The incorporation of VC units in the polymer results in a drop in dynamic modulus because of the reduction in crystallinity. However, the glass-transition temperature is raised therefore, the softening effect observed at room temperature is accompanied by increased brittleness at lower temperatures. These copolymers are normally plasticized in order to avoid this. Small amounts of plasticizer (2—10 wt %) depress T significantly without loss of strength at room temperature. At higher levels of VC, the T of the copolymer is above room temperature and the modulus rises again. A minimum in modulus or maximum in softness is usually observed in copolymers in which T is above room temperature. A thermomechanical analysis of VDC—AN (acrylonitrile) and VDC—MMA (methyl methacrylate) copolymer systems shows a minimum in softening point at 79.4 and 68.1 mol % VDC, respectively (86). 

In addition to chemical analysis a number of physical and mechanical properties are employed to determine cemented carbide quaUty. Standard test methods employed by the iadustry for abrasive wear resistance, apparent grain size, apparent porosity, coercive force, compressive strength, density, fracture toughness, hardness, linear thermal expansion, magnetic permeabiUty, microstmcture, Poisson s ratio, transverse mpture strength, and Young s modulus are set forth by ASTM/ANSI and the ISO. 

Dynamic mechanical thermal analysis has become a powerful tool for the assessment of cure and the study of the effect of extent of sure on film properties and performance (133,134). 

R.J. Clifton, On the Analysis of Elastic/Visco-Plastic Waves of Finite Uniaxial Strain, in Shock Waves and the Mechanical Properties of Solids (edited by J.J. Burke and V. Weiss), Syracuse University Press, 1971, pp. 73-119. 

Another example of static SIMS used in a more quantitative role is in the analysis of extmded polymer blends. The morphology of blended polymers processed by extrusion or molding can be affected by the melt temperature, and pressure, etc. The surface morphology can have an effect on the properties of the molded polymer. Adhesion, mechanical properties, and physical appearance are just a few properties affected by processing conditions. 

Strained set of lattice parameters and calculating the stress from the peak shifts, taking into account the angle of the detected sets of planes relative to the surface (see discussion above). If the assumed unstrained lattice parameters are incorrect not all peaks will give the same values. It should be borne in mind that, because of stoichiometry or impurity effects, modified surface films often have unstrained lattice parameters that are different from the same materials in the bulk form. In addition, thin film mechanical properties (Young s modulus and Poisson ratio) can differ from those of bulk materials. Where pronounced texture and stress are present simultaneously analysis can be particularly difficult. 

The procedures of measuring changes in some physical or mechanical property as a sample is heated, or alternatively as it is held at constant temperature, constitute the family of thermoanalytical methods of characterisation. A partial list of these procedures is differential thermal analysis, differential scanning calorimetry, dilatometry, thermogravimetry. A detailed overview of these and several related techniques is by Gallagher (1992). 

A detailed spectral analysis was undertaken and mechanical properties are described, but no information is reported on the cation binding abilities of the various species thus produced . 

The micromechanics approaches presented in this book are an attempt to predict the mechanical properties of a composite material based on the mechanical properties of its constituent materials. In nearly all fiber-reinforced composite materials, there is considerable difference between expectation and reality. Thus, we must ask what is the usefulness of micromechanical analysis beyond gaining a feeling for why composite materials behave as they do Basically, there are two answers one related to designing a material and one related to designing a structure. 

The mechanical properties of polymers are of interest in all applications where they are used as structural materials. The analysis of the mechanical behavior involves the deformation of a material under the influence of applied forces, and the most important and characteristic mechanical property is the modulus. A modulus is the ratio between the applied stress and the corresponding deformation, the nature of the modulus depending on that of the deformation. Polymers are viscoelastic materials and the high frequencies of most adiabatic techniques do not allow equilibrium to be reached in viscoelastic materials. Therefore, values of moduli obtained by different techniques do not always agree in the literature. 

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