Rapid fabrication of metal-coated composite stereolithography parts

2007 ◽  
Vol 221 (9) ◽  
pp. 1431-1440 ◽  
Author(s):  
Z Zhou ◽  
D Li ◽  
J Zeng ◽  
Z Zhang
Keyword(s):  
Surface Roughness ◽  
Adhesive Strength ◽  
Nickel Coating ◽  
Mechanical Test ◽  
Flexural Modulus ◽  
Test Results ◽  
Fabrication Method ◽  
Rapid Fabrication ◽  
Electrodeposited Nickel ◽  
Strength And Stiffness

In this paper, the rapid fabrication method based on stereolithography (SL) and electrochemical deposition is described in detail and mechanical test results of composite nickel-coated SL parts are presented. Coatings of electrodeposited nickel on SL prototypes result in increases in Young's modulus, UTS, flexural modulus, and strength. Electrodeposited nickel coating has dramatically improved the overall strength and stiffness of SL parts. The adhesive strength of the roughened SL resin-nickel interface is higher than the original. In particular, the influence of the surface roughness on adhesive strength between SL and metal is investigated. Moreover, this paper has presented an application of a structural electrodeposited nickel coating over SL parts to make a functional airfoil model with a complex internal structure and sufficient mechanical strength and stiffness.

Star-shaped arylacetylene resins derived from silicon

2020 ◽  
Vol 40 (8) ◽  
pp. 676-684
Author(s):  
Niping Dai ◽  
Junkun Tang ◽  
Manping Ma ◽  
Xiaotian Liu ◽  
Chuan Li ◽  
...  
Keyword(s):  
High Performance ◽  
Room Temperature ◽  
Mechanical Test ◽  
Flexural Modulus ◽  
Mechanical Analysis ◽  
Reinforced Composites ◽  
Scanning Calorimetry ◽  
Chemical Structures ◽  
Structures And Properties ◽  
High Performance Resin

AbstractStar-shaped arylacetylene resins, tris(3-ethynyl-phenylethynyl)methylsilane, tris(3-ethynyl-phenylethynyl) phenylsilane, and tris (3-ethynyl-phenylethynyl) silane (TEPHS), were synthesized through Grignard reaction between 1,3-diethynylbenzene and three types of trichlorinated silanes. The chemical structures and properties of the resins were characterized by means of nuclear magnetic resonance, fourier-transform infrared spectroscopy, Haake torque rheomoter, differential scanning calorimetry, dynamic mechanical analysis, mechanical test, and thermogravimetric analysis. The results show that the melt viscosity at 120 °C is lower than 150 mPa⋅s, and the processing windows are as wide as 60 °C for the resins. The resins cure at the temperature as low as 150 °C. The good processabilities make the resins to be suitable for resin transfer molding. The cured resins exhibit high flexural modulus and excellent heat-resistance. The flexural modulus of the cured TEPHS at room temperature arrives at as high as 10.9 GPa. Its temperature of 5% weight loss (Td5) is up to 697 °C in nitrogen. The resins show the potential for application in fiber-reinforced composites as high-performance resin in the field of aviation and aerospace.

scholarly journals Performance Study of Grass-Derived Nano-Cellulose and Polycaprolactone Composites for 3D Printing

2021 ◽  
Vol 11 (3) ◽  
pp. 1273
Author(s):  
Chen Feng ◽  
Jiping Zhou ◽  
Xiaodong Xu ◽  
Yani Jiang ◽  
Hongcan Shi ◽  
...  
Keyword(s):  
3D Printing ◽  
Mechanical Test ◽  
Chemical Properties ◽  
Test Results ◽  
Performance Study ◽  
Compression Process ◽  
Ansys Fluent ◽  
Nano Cellulose ◽  
Physical And Chemical ◽  
And Chemical Properties

In recent years, 3D printing has received increasing attention from researchers. This technology overcomes the limitations of traditional technologies by printing precise and personalized scaffold with arbitrary shapes, pore structures, and porosities for the applications in various tissues. The cellulose nanocrystal (CNC) is extracted from Humulus Japonicus (HJS) and mixed with poly(ε-caprolactone) (PCL) to prepare a series of CNC/PCL composites for printing. Based on the analysis of the physical and chemical properties of the series of the CNC/PCL composites, an optimal mass ratio of CNC to PCL was obtained. The Solidworks was used to simulate the stretching and compression process of the scaffolds with three different patterns under an external force. The flow of nutrient solution in the scaffolds with different patterns was simulated by ANSYS FLUENT, and then a new optimization scaffold pattern with a concave hexagon shape was advised based on the simulation results. Collectively, the mechanical test results of the material and scaffold confirmed that the optimal filling amount of the CNC was 5%, and the scaffold pattern with concave hexagon shape exhibited better mechanical properties and suitable for the transport of cells and nutrients, which is expected to be more widely used in 3D printing.

Transient liquid phase bonding of Cu and Al using metallic particles interlayers

2021 ◽  
pp. 095440542098823
Author(s):  
Alireza Zaheri ◽  
Mohammadreza Farahani ◽  
Alireza Sadeghi ◽  
Naser Souri
Keyword(s):  
Liquid Phase ◽  
Mechanical Test ◽  
Transient Liquid Phase ◽  
Transient Liquid Phase Bonding ◽  
Joint Interface ◽  
Test Results ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metallic Particles ◽  
Powder Interlayer

The bonding strength, and microstructures of Cu and Al couples using metallic powders as interlayer during transient liquid phase bonding (TLP bonding) were investigated. The interfacial morphologies and microstructures were studied by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy, and X-ray diffraction. First, to explore the optimum bonding time and temperature, nine samples were bonded without interlayers in a vacuum condition. Mechanical test results indicated that bonding at 560°C in 20 min returns the highest bond strength (84% of Al). This bonding condition was used to join ten samples with powder interlayers. Powders were prepared by mixing different combinations of Cu, Al (+Fe nanoparticles) and Zn. In the bonding zone, different Cu9Al4, CuAl, and CuAl2 intermetallic co-precipitate. The strongest bonding is formed in the sample with the 70Al (+Fe)-30Cu powder interlayer. Powder interlayers present thinner and more uniform intermetallic layers at the joint interface.

scholarly journals A Proposed Fabrication Method of Novel PCL-GEL-HAp Nanocomposite Scaffolds for Bone Tissue Engineering Applications

2010 ◽  
Vol 19 (4) ◽  
pp. 096369351001900 ◽  
Author(s):  
A. Hamlekhan ◽  
M. Mozafari ◽  
N. Nezafati ◽  
M. Azami ◽  
H. Hadipour
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Mechanical Test ◽  
Fibroblast Cell ◽  
Mouse Fibroblast ◽  
Fabrication Method ◽  
Engineering Applications ◽  
Poly Caprolactone

In this study, poly(∊-caprolactone) (PCL), gelatin (GEL) and nanocrystalline hydroxyapatite (HAp) was applied to fabricate novel PCL-GEL-HAp nanaocomposite scaffolds through a new fabrication method. With the aim of finding the best fabrication method, after testing different methods and solvents, the best method and solvents were found, and the nanocomposites were prepared through layer solvent casting combined with freeze-drying. Acetone and distillated water were used as the PCL and GEL solvents, respectively. The mechanical test showed that the increasing of the PCL weight through the scaffolds caused the improvement of the final nanocomposite mechanical behavior due to the increasing of the ultimate stress, stiffness and elastic modulus (8 MPa for 0% wt PCL to 23.5 MPa for 50% wt PCL). The biomineralization investigation of the scaffolds revealed the formation of bone-like apatite layers after immersion in simulated body fluid (SBF). In addition, the in vitro cytotoxity of the scaffolds using L929 mouse fibroblast cell line (ATCC) indicated no sign of toxicity. These results indicated that the fabricated scaffold possesses the prerequisites for bone tissue engineering applications.

Effect of Laser Shock Peening on the Structure and Prosperity of K403 Alloy

2014 ◽  
Vol 670-671 ◽  
pp. 52-55
Author(s):  
Yan Chai ◽  
Wei Feng He ◽  
Guang Yu He ◽  
Yu Qin Li
Keyword(s):  
Surface Roughness ◽  
Grain Boundary ◽  
Compressive Stress ◽  
Residual Compressive Stress ◽  
Laser Shock Peening ◽  
Test Results ◽  
Laser Shock ◽  
Surface Microhardness ◽  
Shock Region ◽  
Shock Peening

To solve the crack and fracture problem in blade made of K403 alloy, the samples of K403 are laser shock processed and then the microstructure, microhardness, residual compressive stress and surface roughness of the samples are tested. The test results show that some grains are observed refined in the grain boundary of shock region, the microhardness improves in a depth of 0.8mm from the surface and the surface microhardness improves 16%, a residual compressive stress which is more than 450MPa is developed in a depth of 1mm from the surface, and obvious changes of the surface roughness are not tested.

Research on Prediction Model of Surface Roughness in Ultrasonic Polishing Nano-ZrO2 Ceramics

2009 ◽  
Vol 69-70 ◽  
pp. 128-132
Author(s):  
Ming Li Zhao ◽  
Bo Zhao ◽  
Yu Qing Wang ◽  
Guo Fu Gao
Keyword(s):  
Surface Roughness ◽  
Orthogonal Test ◽  
Depth Of Cut ◽  
Feed Speed ◽  
Machining Parameters ◽  
Test Results ◽  
Work Situation ◽  
Table Speed ◽  
Abrasive Size ◽  
Regressive Analysis

The orthogonal test of surface roughness in ultrasonic polishing nano-ZrO2 ceramics was carried out in the present paper. Through the test, the influence of machining parameters on the surface roughness was investigated. The test results showed that the influence of abrasive size on surface roughness is the most remarkable, and the other important factors are the depth of cut, on/off work situation of ultrasonic generator, axial feed speed, and working table speed in turns. Furthermore, through the regressive analysis of test data, an empirical formula of surface roughness was established to select reasonable polishing parameters.

Electrodeposited Nickel Coating Reinforced with Chlorophyll‐Reduced Graphene Oxide

2021 ◽  
Author(s):  
Saptarshi Das ◽  
Swastika Banthia ◽  
Jhimli Sarkar Manna ◽  
Debajyoti Palai ◽  
Srijan Sengupta
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Nickel Coating ◽  
Reduced Graphene ◽  
Electrodeposited Nickel

Effects of cross-linking by MgCl2 as an initiator on the properties of EVOH

2020 ◽  
pp. 089270572091331
Author(s):  
Bin Wang ◽  
Chong Lu ◽  
Jing Hu ◽  
Weixin Lu
Keyword(s):  
Mechanical Test ◽  
Barrier Properties ◽  
Thermomechanical Properties ◽  
Cross Linking ◽  
Resonance Spectroscopy ◽  
Test Results ◽  
Ethylene Vinyl Alcohol ◽  
Ftir Spectrometry ◽  
Stretching Vibration ◽  
C Nmr

Ethylene vinyl alcohol (EVOH) with excellent barrier properties has insufficient thermomechanical properties. The introduction of magnesium chloride (MgCl2) as an initiator in EVOH blends improved its properties by cross-linking. Torque behavior and gel experiment analysis indicated that a cross-linking in EVOH was formed. The cross-linking mechanism was confirmed through 13C nuclear magnetic resonance spectroscopy (13C NMR) and Fourier-transform infrared (FTIR) spectrometry. In 13C NMR spectra, the splitting peaks of CH carbon and CH2 carbon tended to disappear, and the stretching vibration peak of –C=C– was observed in the FTIR spectra. The formation of hydrogen bond between MgCl2 and EVOH destroyed the intramolecular and intermolecular hydrogen bonds of EVOH, which contributed to the dehydration of –OH to form –C=C–, and –C=C– was the basis for a cross-linking reaction. The thermal analysis of blends demonstrated that the melting temperature and crystallization temperature decreased, and the crystallinity gradually disappeared when the MgCl2 content increased. Glass transition temperature significantly increased as the intermolecular force enhanced. Thermogravimetric analysis showed that a cross-linked structure could improve the thermostability of EVOH with an increase in the MgCl2 content. Mechanical test results revealed a remarkable increase in the tensile strength of EVOH as the MgCl2 content increased.

scholarly journals Characterization of lightweight concrete made of palm oil clinker aggregates

2018 ◽  
Vol 250 ◽  
pp. 03002 ◽  
Author(s):  
Muhammad Sazlly Nazreen ◽  
Roslli Noor Mohamed ◽  
Mariyana Aida Ab Kadir ◽  
Nazry Azillah ◽  
Nazirah Ahmad Shukri ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Palm Oil ◽  
Lightweight Concrete ◽  
Flexural Modulus ◽  
Pulse Velocity ◽  
Normal Weight ◽  
Lightweight Aggregate Concrete ◽  
Fine Aggregate ◽  
Test Results ◽  
Aggregate Concrete

Lightweight concrete (LWC) has been identified as an innovative technique for construction purposes. Lightweight concrete can be categorized into three different types which are no-fine aggregate concrete, lightweight aggregate concrete and aerated concrete. This paper studied the characteristic of the lightweight concrete in term of mechanical properties utilizing the palm oil clinker (POC) as lightweight aggregates. Two mixes of lightweight concrete were developed, namely as POCC100 and POCC50 where each mix utilized 100% and 50% of total replacement to fine and coarse aggregates, respectively. The fresh and hardened POC concrete was tested and compared to the normal concrete (NC). The hardened state of the concrete was investigated through density test, ultrasonic pulse velocity, cube compressive, splitting tensile, flexural, modulus of elasticity and Poisson's ratio. From density test results, POC falls into the category of lightweight concrete with a density of 1990.33 kg/m3, which are below than normal weight concrete density. The mechanical properties test results on POCC100 and POCC50 showed that the concrete compressive strength was comparable about 85.70% and 96% compared to NC specimen, respectively. For the flexural strength, POCC50 and POCC100 were comparable about 98% and 97% to NC specimen, respectively. While splitting tensile strength of POCC50 and POCC100 was only 0.6% and 4% lower than NC specimen, respectively. In terms of sustainability of solid waste management, the application of the POC in construction will reduce the redundant of by-products resulted from the palm oil industries. After undergoing various testing of concrete mechanical properties, it can be concluded that POC aggregates was compatible to be used in ligtweight concrete mix proportion.

scholarly journals Natural Mordenite from Spain as Pozzolana

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1220
Author(s):  
Leticia Presa ◽  
Jorge L. Costafreda ◽  
Domingo A. Martín ◽  
Isabel Díaz
Keyword(s):  
Mechanical Test ◽  
Low Cost ◽  
Principal Component ◽  
Test Results ◽  
Mechanical Compression ◽  
San Jose ◽  
X Ray Diffraction ◽  
Pozzolanic Cement ◽  
Natural Clinoptilolite ◽  
Potential Use

This work deals with anomalous concentrations of natural mordenite in the southeast of Spain. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies evidenced that the samples contain mainly monomineral zeolitic phase of mordenite (70% to 74%), usually accompanied by smectite (montmorillonite), the principal component of bentonite. A study of the applicability of these zeolites is presented to establish the potential use as pozzolanic cements. For comparative purposes, synthetic commercial mordenite is also characterized and tested. The initial mixtures were prepared using cement and mordenite at a 75:25 ratio. Chemical analysis and a pozzolanicity test showed the high pozzolanic character. These mixtures were further added to sand and water, yielding the cement specimens to be used as concrete. Mechanical test results showed that the mechanical compression at 7 and 28 days fall into the range of 19.23 to 43.05 MegaPascals (MPa) for the cement specimens built with natural mordenites. The obtained results fall in the same range of cement specimens prepared with natural clinoptilolite, using mixtures within the European requirement for commercial concretes. Thus, these results and the low cost of natural mordenite of San José de los Escullos deposit supports the potential use of natural mordenite as pozzolanic cement.

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