Papers by Keyword: 3D Microstructure

Abstract: The material of the tubes has suffered localized overheating and corrosion, probably as a result of local heat flux impingement phenomenon, combined with high temperature corrosion. Boiler tubes that experienced failure indications were tubes material SA 213 T22 with the dominant alloy elements is Cr. Materials with these specifications are which should be resistant to corrosion, so it is necessary to carry out laboratory testing to answer suspected indications of failure. The methodology of analysis and identification carried out is by observing the microstructure in 3 dimensions supported by other mechanical tests, namely visual observation, hardness testing, chemical composition testing using SEM and EDAX and testing the chemical composition of the material using a spectrum analyzer. Observation using an optical microscope shows that the microstructure condition of the tube is ferritic and the results of 3D metallography observations show that the tube has undergone micro crack with a measured depth of 1853,28 μm. After the metallography testing is carried out, the hardness test is carried out with the hardness vickers (HV) unit and the minimum hardness is 149 HV and the maximum hardness is 177 HV. Testing of the chemical composition of the deposit showed that there were chemical elements found in seawater that trigger corrosion such as sodium and chlorine which enter the water vapor system. The results showed that the tube had pitting corrosion, which was indicated by the presence of microcrack at the grain boundaries and an oxide deposit had been formed which would cause an overheating phenomenon and deterioration.

Abstract: Properties of an interpenetrating metal–ceramic composite with freeze-cast preforms are investigated. For the estimation of elastic properties of the composite numerical homogenization approaches for 2D and 3D finite element models are implemented. The FE models are created based on micro-computed tomography (μCT) images. The results of the numerical 2D and 3D modeling coincide and are in good agreement with available experimental measurements of elastic properties.

Abstract: This paper presents a research on 3D part fabrication from composition of photo initiator (Phenylbis (2,4,6-trimethylbenzoyl)), photo absorber (Sudan I) and 1, 6-Hexanediol polymer effect based on curing parameters. A DLP projector was used as energy light source which initiated the photo reactive polymer at three different light source distances with three different exposed time to evaluate photoreactive polymer solidification phenomena. The experiment results obtained shows that Sudan I composition, light intensity value and exposure time of the varied photo absorber give significant effect to layer thicknes, surface roughness and hardness value. These works also prove that photo absorber composition solution gave a different mechanical properties effect for 3D microstructure fabrication.

Abstract: This paper presents a research on composition photo absorber (Sudan I) effect based on curing parameter, the Liquid Crystal Display (LCD) projector as energy light source initiated the photo reactive polymer. The polymer based material with composition of 1, 6-Hexanediol dicrylate, Phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide with varied Sudan I concentration was used to build 3D structures. The structure was fabricated with three different photo absorber concentrations 0.002%, 0.003%. and 0.006%. of Sudan I. In this experiment the photoreactive polymer solidification phenomena was evaluated.The experiment result obtained, that exposed time of the varied photo absorber was most significantly affect the surface roughness values and the solidification layer time regardless the layer thickness. This work represents that photo absorber composition solution gave a different characteristics for 3D microstructure fabrication.

Abstract: This paper presents a research progress on composition photoabsorber effect the solidification time and layer thickness of 3D structures fabrication using Liquid Crystal Display (LCD) projector as energy light source to initiate the photoreactive polymer. The polymer based material with composition of 1,6-Hexanediol dicrylate, Phenylbis(2,4,6-trimethylbenzoyl)- phosphine oxide with varied Sudan I concentrations was used to build 3D structures. The structure was fabricated using a three different photo absorber composition of Sudan I then the photoreactive polymer solidification phe¬nomena was evaluated. Based on the result obtained, higher exposed time of the photo absorber will reduced the surface roughness values and increased the solidification layer time. This work represents that photo absorber composition solution gave a different characteristics for 3D microstructure fabrication.

Abstract: A 3D microstructure, measured by high-energy x-ray diffraction microscopy, is used as an input to a parallelized viscoplastic Fast Fourier Transform code (VPFFT) to simulate a tensile test. Distributions of strain, damage accumulation, neighbor interactions, and Schmid factor mismatch throughout the microstructure are calculated. These results will form the basis of a direct comparison to microstructure maps that track plastic deformation in the real sample.

Abstract: Flower-like LLM-105 three-dimensional microstructures, which consisted of LLM-105 microrods with rectangular cross-sections, were prepared via a smiple template- and surfactant-free recrystallization process using [Bmim]CF₃SO₃ as good solvent and water as poor solvent. A tentative mechanism for the growth of the flower-like LLM-105 three-dimensional microstructures was proposed on the basis of the analysis of X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). Comparing with LLM-105 raw material, the thermal decomposition took place at lower temperature and the weight loss has increased for the flower-like three-dimensional microstructures in the differential scanning calorimetric/thermogravimetric (DSC/TG) measurements.

Abstract: This paper describes some aspects of reconstruction of microstructures in three dimensions. A distinction is drawn between tomographic approaches that seek to characterize specific volumes of material, either with or without diffraction, and statistical approaches that focus on particular aspects of microstructure. A specific example of the application of the statistical approach is given for an aerospace aluminum alloy in which the distributions of coarse constituent particles are modeled. Such distributions are useful for modeling fatigue crack initiation and propagation.