Optimization of fiber prediction model coefficients in injection molding simulation based on micro computed tomography

Metal injection molding (MIM) is a combination of metal powder and injection molding technology. The main advantage of this technology for material parts with small and complex shape is to manufacture cost-effective and high-volume products. The main processing steps include mixing, injection molding, debinding , sintering, and hot isostatic pressing (HIP) in order to reduce internal porosity of metals, then to improve mechanical properties. This study is based on non-destructive testing method to determine the possible defect inside the internal structure of the MIM parts. Three types of parts with and without HIP were evaluated investigated in this study. The micro computed tomography (Micro-CT) is used to scan these parts. Based the reconstructed section images from CT, the defects can be identified. It showed that with HIP the much of detects could be reduced. To conclude, Micro CT could be used to detect, in a non-destructive way, the internal detect within MIM parts can be found out in the micro-CT images, so that the manufacturing process could be modified to improve the quality of MIM parts.

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Comparison between Middle-Face Model and 3D Model and Experiment of Gas-Assisted Injection Molding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.403-408.3656 ◽

2011 ◽

Vol 403-408 ◽

pp. 3656-3660

Author(s):

Tie Geng ◽

Qing Hai Ren ◽

Yan Yun Zhang ◽

Wei Qing Tu ◽

Dan Dan Liu

Keyword(s):

Injection Molding ◽

3D Model ◽

Physical Experiment ◽

Experimental Results ◽

Molding Process ◽

Face Model ◽

Simulation Based ◽

Injection Molding Simulation ◽

Simulation Results ◽

D Model

Based on the research about the injection molding simulation technology such as 2.5-d model and 3D model, Numerical analysis on a same gas-assisted product was implemented using Moldflow software’s middle-face model and 3D model technology, and the physical experiment was also implemented. Through comparing the simulation results and experimental results, it shown that the time of the gas-assisted injection molding simulation based on 3D model is long, but the simulation results are more in line with experimental results than middle-face model. The numerical simulation using 3D model can truly and reliably predict the product’s molding process, and meet the demand to guide production.

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Identification of Fibrotic Thickening as Early Marker of Aortic Valve Stenosis Using X-Ray Micro Computed Tomography and Optical Coherence Tomography

The Thoracic and Cardiovascular Surgeon ◽

10.1055/s-0036-1571661 ◽

2016 ◽

Vol 64 (S 01) ◽

Author(s):

A. Jannasch ◽

C. Schnabel ◽

M. Santini ◽

S. Fest-Santini ◽

M. Lorenzi ◽

...

Keyword(s):

Computed Tomography ◽

Optical Coherence Tomography ◽

Aortic Valve ◽

Aortic Valve Stenosis ◽

Optical Coherence ◽

Micro Computed Tomography ◽

X Ray ◽

Early Marker

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Cortical and trabecular bone parameters from HR-Pqct images at the Tibia: a local comparison with synchrotron radiation micro-computed tomography

Bone Abstracts ◽

10.1530/boneabs.1.pp316 ◽

2013 ◽

Author(s):

Agnes Ostertag ◽

Francoise Peyrin ◽

Sylvie Fernandez ◽

Jean-Denis Laredo ◽

Vernejoul Marie-Christine De ◽

...

Keyword(s):

Computed Tomography ◽

Synchrotron Radiation ◽

Trabecular Bone ◽

Micro Computed Tomography ◽

Bone Parameters ◽

Local Comparison

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Morphology and Affinities of Ampelocissites Seeds (Vitaceae: Ampelopsis clade) from the Paleogene of Texas, USA

Systematic Botany ◽

10.1600/036364420x15935294613400 ◽

2020 ◽

Vol 45 (3) ◽

pp. 478-482

Author(s):

Steven R. Manchester

Keyword(s):

Computed Tomography ◽

Cross Sections ◽

Seed Coat ◽

Ct Scanning ◽

Seed Morphology ◽

Early Eocene ◽

Micro Computed Tomography ◽

X Ray ◽

Fossil Seeds ◽

Fossil Genus

Abstract—The type material on which the fossil genus name Ampelocissites was established in 1929 has been reexamined with the aid of X-ray micro-computed tomography (μ-CT) scanning and compared with seeds of extant taxa to assess the relationships of these fossils within the grape family, Vitaceae. The specimens were collected from a sandstone of late Paleocene or early Eocene age. Although originally inferred by Berry to be intermediate in morphology between Ampelocissus and Vitis, the newly revealed details of seed morphology indicate that these seeds represent instead the Ampelopsis clade. Digital cross sections show that the seed coat maintains its thickness over the external surfaces, but diminishes quickly in the ventral infolds. This feature, along with the elliptical chalaza and lack of an apical groove, indicate that Ampelocissites lytlensis Berry probably represents Ampelopsis or Nekemias (rather than Ampelocissus or Vitis) and that the generic name Ampelocissites may be useful for fossil seeds with morphology consistent with the Ampelopsis clade that lack sufficient characters to specify placement within one of these extant genera.

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Faculty Opinions recommendation of A detailed comparative study of high-resolution ultrasound and micro-computed tomography for detection of arthritic bone erosions.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.10849956.11772056 ◽

2011 ◽

Author(s):

Thomas Link ◽

Janina Patsch

Keyword(s):

Computed Tomography ◽

High Resolution ◽

Comparative Study ◽

Micro Computed Tomography ◽

Bone Erosions

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INVESTIGATION OF AUBRITES THROUGH INTEGRATION OF 3D MODAL MINERALOGY WITH X-RAY MICRO-COMPUTED TOMOGRAPHY AND GEOCHEMISTRY

10.1130/abs/2018am-317290 ◽

2018 ◽

Author(s):

Zoë E. Wilbur ◽

◽

Arya Udry ◽

Daniel M. Coleff ◽

...

Keyword(s):

Computed Tomography ◽

Micro Computed Tomography ◽

X Ray

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Micro-Computed Tomography Analysis of Subchondral Bone Regeneration Using Osteochondral Scaffolds in an Ovine Condyle Model

Applied Sciences ◽

10.3390/app11030891 ◽

2021 ◽

Vol 11 (3) ◽

pp. 891

Author(s):

Taylor Flaherty ◽

Maryam Tamaddon ◽

Chaozong Liu

Keyword(s):

Computed Tomography ◽

Bone Regeneration ◽

Subchondral Bone ◽

Volume Ratio ◽

Bone Volume ◽

Osteochondral Defects ◽

Micro Ct ◽

Micro Computed Tomography ◽

Trabecular Thickness ◽

Osteochondral Scaffold

Osteochondral scaffold technology has emerged as a promising therapy for repairing osteochondral defects. Recent research suggests that seeding osteochondral scaffolds with bone marrow concentrate (BMC) may enhance tissue regeneration. To examine this hypothesis, this study examined subchondral bone regeneration in scaffolds with and without BMC. Ovine stifle condyle models were used for the in vivo study. Two scaffold systems (8 mm diameter and 10 mm thick) with and without BMC were implanted into the femoral condyle, and the tissues were retrieved after six months. The retrieved femoral condyles (with scaffold in) were examined using micro-computed tomography scans (micro-CT), and the micro-CT data were further analysed by ImageJ with respect to trabecular thickness, bone volume to total volume ratio (BV/TV) ratio, and degree of anisotropy of bone. Statistical analysis compared bone regeneration between scaffold groups and sub-set regions. These results were mostly insignificant (p < 0.05), with the exception of bone volume to total volume ratio when comparing scaffold composition and sub-set region. Additional trends in the data were observed. These results suggest that the scaffold composition and addition of BMC did not significantly affect bone regeneration in osteochondral defects after six months. However, this research provides data which may guide the development of future treatments.

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