Studies on mechanical properties of polymer composites by X-ray diffraction. I. Residual stress in epoxy resin by X-ray diffraction

ABSTRACTPt-IrO2 films, approximately 200 nm thick, were fabricated by co-sputter deposition of Pt and Ir in an Ar-O2 mixture followed by annealing at 700°C in O2 for 4 hours. X-ray photoelectron spectroscopy and x-ray diffraction measurements indicate the presence of IrO2 throughout the thickness of the films. After a thermal cycle in vacuum to 700°C, the room temperature residual stress is significantly lower in the internally oxidized films than in pure Pt films of similar thickness subjected to identical cycling. Initial analysis of the behavior of the films during thermal cycling indicates that the primary cause for the difference in residual stress level is a decrease in the thermoelastic slope associated with the introduction of IrO2.

Download Full-text

Investigating The Effect of Magnetite (Fe3O4) Nanoparticles on Mechanical Properties of Epoxy Resin

Engineering and Technology Journal ◽

10.30684/etj.v39i6.2063 ◽

2021 ◽

Vol 39 (6) ◽

pp. 986-995

Author(s):

Ehab Q. Kaadhm ◽

Khansaa D. Salman ◽

Ahmed H. Reja

Keyword(s):

Mechanical Properties ◽

Epoxy Resin ◽

Fe3o4 Nanoparticles ◽

Matrix Material ◽

X Ray Diffraction ◽

Casting Method ◽

X Ray ◽

Magnetite Fe3o4 ◽

Reinforcing Material ◽

Flexural Tests

In this paper, study the effects of magnetite nanomaterial Fe3O4 on the mechanical properties of epoxy. Dispersion of Fe3O4 nanoparticles in the epoxy resin was performed by ultrasonication. The samples of the nanocomposites were prepared using the casting method. The nanocomposites contain epoxy resins as a matrix material incorporated by different weight percentages of magnetite Fe3O4 that varies from 0wt.% to 15wt.% as a reinforcing material. The epoxy with the additive reinforcement materials Fe3O4 was slowly mixed in a sonication bath for 15 minutes, then the mixture poured into silicon molds. Field Emission Scanning Electron Microscopy FESEM and X-ray diffraction spectra XRD were used to characterize the morphological and structural properties of preparing samples and the distribution of Fe3O4 nanoparticles to the epoxy resin. Mechanical testing consists of tensile, hardness shore, and three-point flexural tests were performed on the samples at room temperature according to ASTM standards. The results showed that reinforcement by 15wt.% of Fe3O4 nanoparticles maximizes these mechanical properties of nanocomposites compared with pure epoxy except for the young modulus's preferred weight at 9 wt.%, this is due to aggregation of the additives nanomaterials in epoxy resin above 9 wt.%.

Download Full-text

Spatial Residual Stress Distribution in Multi-Phase Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.885.135 ◽

2017 ◽

Vol 885 ◽

pp. 135-140

Author(s):

Adám Filep ◽

Márton Benke ◽

Valéria Mertinger

Keyword(s):

Mechanical Properties ◽

Residual Stress ◽

Stress Distribution ◽

Stress Gradient ◽

Residual Stress Distribution ◽

X Ray Diffraction ◽

X Ray ◽

Stress Measurements ◽

Duplex Steel ◽

Multi Phase

Residual stress measurements were carried out on duplex steel samples using X-ray diffraction technique. Directional residual stress was investigated on the surface of the heat effected zone of joints. Spatial residual stress distribution were examined in the ferrite and austenite phases separately, using different radiation-ray source. The different mechanical properties of each phases were taken into account during the stress calculations. Noticeable stress gradient was observed between ferrite and austenite phases.

Download Full-text

Mechanical properties of FeAlSi powders prepared by mechanical alloying from different initial feedstock materials

Matériaux & Techniques ◽

10.1051/mattech/2018063 ◽

2019 ◽

Vol 107 (2) ◽

pp. 207 ◽

Cited By ~ 2

Author(s):

Jaroslav Čech ◽

Petr Haušild ◽

Miroslav Karlík ◽

Veronika Kadlecová ◽

Jiří Čapek ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Alloying ◽

Young’S Modulus ◽

Milling Time ◽

Young's Modulus ◽

Element Model ◽

X Ray Diffraction ◽

X Ray ◽

Powder Particles ◽

Complete Homogenization

FeAl20Si20 (wt.%) powders prepared by mechanical alloying from different initial feedstock materials (Fe, Al, Si, FeAl27) were investigated in this study. Scanning electron microscopy, X-ray diffraction and nanoindentation techniques were used to analyze microstructure, phase composition and mechanical properties (hardness and Young’s modulus). Finite element model was developed to account for the decrease in measured values of mechanical properties of powder particles with increasing penetration depth caused by surrounding soft resin used for embedding powder particles. Progressive homogenization of the powders’ microstructure and an increase of hardness and Young’s modulus with milling time were observed and the time for complete homogenization was estimated.

Download Full-text

Microstructure and Physical Properties of Clay-Polymer Composites

MRS Proceedings ◽

10.1557/proc-628-cc11.14 ◽

2000 ◽

Vol 628 ◽

Author(s):

T.N. Blanton ◽

D. Majumdar ◽

S.M. Melpolder

Keyword(s):

Composite Materials ◽

Physical Properties ◽

Polymer Composites ◽

Basal Plane ◽

X Ray Diffraction ◽

X Ray ◽

Layered Clay

ABSTRACTClay-polymer nanoparticulate composite materials are evaluated by the X-ray diffraction technique. The basal plane spacing provided information about the degree of intercalation and exfoliation of the 2: 1 layered clay structure. Both intercalation and exfoliation are controlled by the identity of the polymer and the clay:polymer ratio.

Download Full-text

Enhancement of Chloroprene/Natural/Butadiene Rubber Nanocomposite Properties Using Organoclays and Their Combination with Carbon Black as Fillers

Polymers ◽

10.3390/polym13071085 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1085

Author(s):

Patricia Castaño-Rivera ◽

Isabel Calle-Holguín ◽

Johanna Castaño ◽

Gustavo Cabrera-Barjas ◽

Karen Galvez-Garrido ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Black ◽

High Performance ◽

Rubber Matrix ◽

Butadiene Rubber ◽

X Ray Diffraction ◽

X Ray ◽

Rubber Blends ◽

Ft Ir ◽

Chloroprene Rubber

Organoclay nanoparticles (Cloisite® C10A, Cloisite® C15) and their combination with carbon black (N330) were studied as fillers in chloroprene/natural/butadiene rubber blends to prepare nanocomposites. The effect of filler type and load on the physical mechanical properties of nanocomposites was determined and correlated with its structure, compatibility and cure properties using Fourier Transformed Infrared (FT-IR), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and rheometric analysis. Physical mechanical properties were improved by organoclays at 5–7 phr. Nanocomposites with organoclays exhibited a remarkable increase up to 46% in abrasion resistance. The improvement in properties was attributed to good organoclay dispersion in the rubber matrix and to the compatibility between them and the chloroprene rubber. Carbon black at a 40 phr load was not the optimal concentration to interact with organoclays. The present study confirmed that organoclays can be a reinforcing filler for high performance applications in rubber nanocomposites.

Download Full-text

Statistical analysis of the reproducibility of residual stress measurements in cold extruded parts

Archive of Applied Mechanics ◽

10.1007/s00419-021-01953-x ◽

2021 ◽

Author(s):

Fabian Jaeger ◽

Alessandro Franceschi ◽

Holger Hoche ◽

Peter Groche ◽

Matthias Oechsner

Keyword(s):

Residual Stress ◽

Statistical Analysis ◽

Stress Measurement ◽

Industrial Applications ◽

Cold Extrusion ◽

X Ray Diffraction ◽

Forming Process ◽

X Ray ◽

Stress States ◽

Key Aspects

AbstractCold extruded components are characterized by residual stresses, which originate from the experienced manufacturing process. For industrial applications, reproducibility and homogeneity of the final components are key aspects for an optimized quality control. Although striving to obtain identical deformation and surface conditions, fluctuation in the manufacturing parameters and contact shear conditions during the forming process may lead to variations of the spatial residual stress distribution in the final product. This could lead to a dependency of the residual stress measurement results on the relative axial and circumferential position on the sample. An attempt to examine this problem is made by the employment of design of experiments (DoE) methods. A statistical analysis of the residual stress results generated through X-Ray diffraction is performed. Additionally, the ability of cold extrusion processes to generate uniform stress states is analyzed on specimens of austenitic stainless steel 1.4404 and possible correlations with the pre-deformed condition are statistically examined. Moreover, the influence of the coating, consisting of oxalate and a MoS2 based lubricant, on the X-Ray diffraction measurements of the surface is investigated.

Download Full-text

The Potential for Natural Stones from Northeastern Brazil to Be Used in Civil Construction

Minerals ◽

10.3390/min11050440 ◽

2021 ◽

Vol 11 (5) ◽

pp. 440

Author(s):

Fabiana Pereira da Costa ◽

Jucielle Veras Fernandes ◽

Luiz Ronaldo Lisboa de Melo ◽

Alisson Mendes Rodrigues ◽

Romualdo Rodrigues Menezes ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Chemical Resistance ◽

Mechanical Analysis ◽

Northeastern Brazil ◽

X Ray Diffraction ◽

X Ray ◽

Chemical Agents ◽

Natural Stones

Natural stones (limestones, granites, and marble) from mines located in northeastern Brazil were investigated to discover their potential for use in civil construction. The natural stones were characterized by chemical analysis, X-ray diffraction, differential thermal analysis, and optical microscopy. The physical-mechanical properties (apparent density, porosity, water absorption, compressive and flexural strength, impact, and abrasion) and chemical resistance properties were also evaluated. The results of the physical-mechanical analysis indicated that the natural stones investigated have the potential to be used in different environments (interior, exterior), taking into account factors such as people’s circulation and exposure to chemical agents.

Download Full-text