Special Issue on Rapid Prototyping

2012 ◽  
Vol 6 (5) ◽  
pp. 569-569 ◽  
Author(s):  
Koichi Morishige ◽  
Masahiro Anzai ◽  
Hiroyuki Narahara
Keyword(s):  
Rapid Prototyping ◽  
High Strength ◽  
Production Equipment ◽  
Processing Method ◽  
Layered Manufacturing ◽  
Special Issue ◽  
Cross Sectional ◽  
3D Cad ◽  
Material Development ◽  
Cad Cam

Layered manufacturing is the generic name for a processing method used to obtain an actual model by calculating cross-sectional shapes from 3D CAD data and stacking these shapes. Because it can realize any shape without needing skills for devising a processing method and fabricating fixtures, layered machining is expected to realize 3D printing that enables even inexperienced or amateur operators to obtain actual 3D shapes. Since the model such as injection molding can be fabricated without using dies and molds, layered manufacturing is now called rapid prototyping (RP). Since ever manufacturing of high-strength materials has become available, RP applications have been deployed in areas from models for more confirmation of shape to functional models attached to prototypes such as engines and used for test runs. In addition, the new concepts called rapid manufacturing (RM) and rapid tooling (RT), which are used in the manufacture of low-volume products and production equipment, have been proposed and implemented. This special issue focuses on RP technology. Among its many interesting papers are those that focus on new fabrication techniques, material development for RP, CAD/CAM systems for RP, new RP systems, and applications for RP. We are certain that you will find this issue both interesting and informative. We thank the authors for their generous cooperation and the editing staff for its many contributions.

3D CAD, CAM and Rapid Prototyping Applied for Cam Fabrication

2014 ◽  
Vol 658 ◽  
pp. 553-556
Author(s):  
Daniel Besnea ◽  
Georgeta Ionascu ◽  
Mihai Avram ◽  
Lucian Bogatu ◽  
Alina Spanu
Keyword(s):  
Rapid Prototyping ◽  
Fused Deposition Modeling ◽  
Product Configuration ◽  
Layer By Layer ◽  
3D Cad ◽  
Fused Deposition ◽  
Modeling Process ◽  
Cad Cam ◽  
Deposition Modeling ◽  
Development Area

In this paper, a comparison between CNC manufacturing and Rapid Prototyping technology (FDM – Fused Deposition Modeling process), applied for a cam fabrication, is presented. In the products development area, a substantial support is offered by models, as intermediate between product configuration and technology design. The CAD/CAM/CNC technology is a widely used technique for creating prototypes, as well as production parts, using a subtractive type material-removal procedure from a semi-manufactured article. The rapid prototyping (RP) technologies are additive processes, where the part is built up layer by layer until done, directly from the 3D CAD model, within the precision limits of the chosen process. Similarities and differences between these two coexisting computer driven prototyping processes, the subtractive CNC 3 – axes milled part production and the additive RP/ FDM technique, are pointed out for a disk cam manufacturing as sample part.

The stabilization of B.C.C. Cu in Cu/Nb nanolayered composites

1996 ◽  
Vol 54 ◽  
pp. 228-229
Author(s):  
H. Kung ◽  
A.J. Griffin ◽  
Y.C. Lu ◽  
K.E. Sickafus ◽  
T.E. Mitchell ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Layer Thickness ◽  
Volume Fraction ◽  
Ion Beam ◽  
High Strength ◽  
Cross Sectional ◽  
Metastable Structure ◽  
High Resolution Tem ◽  
Potential Improvement ◽  
Two Phases

Materials with compositionally modulated structures have gained much attention recently due to potential improvement in electrical, magnetic and mechanical properties. Specifically, Cu-Nb laminate systems have been extensively studied mainly due to the combination of high strength, and superior thermal and electrical conductivity that can be obtained and optimized for the different applications. The effect of layer thickness on the hardness, residual stress and electrical resistivity has been investigated. In general, increases in hardness and electrical resistivity have been observed with decreasing layer thickness. In addition, reduction in structural scale has caused the formation of a metastable structure which exhibits uniquely different properties. In this study, we report the formation of b.c.c. Cu in highly textured Cu/Nb nanolayers. A series of Cu/Nb nanolayered films, with alternating Cu and Nb layers, were prepared by dc magnetron sputtering onto Si {100} wafers. The nominal total thickness of each layered film was 1 μm. The layer thickness was varied between 1 nm and 500 nm with the volume fraction of the two phases kept constant at 50%. The deposition rates and film densities were determined through a combination of profilometry and ion beam analysis techniques. Cross-sectional transmission electron microscopy (XTEM) was used to examine the structure, phase and grain size distribution of the as-sputtered films. A JEOL 3000F high resolution TEM was used to characterize the microstructure.

APPLYING THE ISF TECHNOLOGY TO PRODUCE THE CAR PART MODELS

2010 ◽  
Vol 13 (4) ◽  
pp. 91-98
Author(s):  
Tuan Dinh Phan ◽  
Binh Thien Nguyen ◽  
Dien Khanh Le ◽  
Phuong Hoang Pham
Keyword(s):  
Rapid Prototyping ◽  
Incremental Sheet Forming ◽  
Cad Model ◽  
Post Processing ◽  
Technological Parameters ◽  
Batch Production ◽  
Complex Products ◽  
3D Cad ◽  
Real Size ◽  
Single Batch

The paper presents an application the research results previously done by group on the influence of technological parameters to the deformation angle and finish surface quality in order to choose technology parameters for the incremental sheet forming (ISF) process to produce products for the purpose of rapid prototyping or single-batch production, including all steps from design and process 3D CAD model, calculate and select the technological parameters, setting up manufacturing and the stage of post-processing. The samples formed successfully showed high applicability of this technology to practical work, the complex products with the real size can be produced in industries: automotive, motorcycle, civil...

scholarly journals Editorial for Special Issue “Leaching of Rare Earth Elements from Various Sources”

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 164
Author(s):  
Kenneth N. Han
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
High Strength ◽  
Green Energy ◽  
High Tech ◽  
Special Issue ◽  
Important Group ◽  
Military Applications

Rare earth elements (REEs) have become an important group of metals used in many high-tech industries, including high-strength magnets, plasma TVs, various military applications, and clean and efficient green energy industries [...]

scholarly journals Tempforming as an Advanced Processing Method for Carbon Steels

Metals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1566
Author(s):  
Anastasiya Dolzhenko ◽  
Rustam Kaibyshev ◽  
Andrey Belyakov
Keyword(s):  
Impact Toughness ◽  
Crack Propagation ◽  
Large Strain ◽  
High Strength ◽  
Close Relation ◽  
Carbon Steels ◽  
Processing Method ◽  
Propagation Mode ◽  
Displacement Curve ◽  
The Impact

The microstructural mechanisms providing delamination toughness in high-strength low-alloyed steels are briefly reviewed. Thermo-mechanical processing methods improving both the strength and impact toughness are described, with a close relation to the microstructures and textures developed. The effect of processing conditions on the microstructure evolution in steels with different carbon content is discussed. Particular attention is paid to tempforming treatment, which has been recently introduced as a promising processing method for high-strength low-alloyed steel semi-products with beneficial combination of strength and impact toughness. Tempforming consists of large strain warm rolling following tempering. In contrast to ausforming, the steels subjected to tempforming may exhibit an unusual increase in the impact toughness with a decrease in test temperature below room temperature. This phenomenon is attributed to the notch blunting owing to easy splitting (delamination) crosswise to the principle crack propagation. The relationships between the crack propagation mode, the delamination fracture, and the load-displacement curve are presented and discussed. Further perspectives of tempforming applications and promising research directions are outlined.

scholarly journals Experimental Investigation into Corrosion Effect on Mechanical Properties of High Strength Steel Bars under Dynamic Loadings

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Hui Chen ◽  
Jinjin Zhang ◽  
Jin Yang ◽  
Feilong Ye
Keyword(s):  
Mechanical Properties ◽  
Strain Rate ◽  
Dynamic Loading ◽  
High Strength Steel ◽  
High Strength ◽  
Tensile Tests ◽  
Reinforcing Steel ◽  
Test Results ◽  
Cross Sectional ◽  
Steel Bars

The tensile behaviors of corroded steel bars are important in the capacity evaluation of corroded reinforced concrete structures. The present paper studies the mechanical behavior of the corroded high strength reinforcing steel bars under static and dynamic loading. High strength reinforcing steel bars were corroded by using accelerated corrosion methods and the tensile tests were carried out under different strain rates. The results showed that the mechanical properties of corroded high strength steel bars were strain rate dependent, and the strain rate effect decreased with the increase of corrosion degree. The decreased nominal yield and ultimate strengths were mainly caused by the reduction of cross-sectional areas, and the decreased ultimate deformation and the shortened yield plateau resulted from the intensified stress concentration at the nonuniform reduction. Based on the test results, reduction factors were proposed to relate the tensile behaviors with the corrosion degree and strain rate for corroded bars. A modified Johnson-Cook strength model of corroded high strength steel bars under dynamic loading was proposed by taking into account the influence of corrosion degree. Comparison between the model and test results showed that proposed model properly describes the dynamic response of the corroded high strength rebars.

Strain-Rate Effect on the Tensile Behaviour of High Strength Alloys

2011 ◽  
Vol 82 ◽  
pp. 124-129 ◽  
Author(s):  
Ezio Cadoni ◽  
Matteo Dotta ◽  
Daniele Forni ◽  
Stefano Bianchi
Keyword(s):  
Strain Rate ◽  
Rate Sensitivity ◽  
High Strength ◽  
Constitutive Law ◽  
Tensile Behaviour ◽  
Strain Rates ◽  
Cross Sectional ◽  
Split Hopkinson Tensile Bar ◽  
Wide Range ◽  
First Results

In this paper the first results of the mechanical characterization in tension of two high strength alloys in a wide range of strain rates are presented. Different experimental techniques were used for different strain rates: a universal machine, a Hydro-Pneumatic Machine and a JRC-Split Hopkinson Tensile Bar. The experimental research was developed in the DynaMat laboratory of the University of Applied Sciences of Southern Switzerland. An increase of the stress at a given strain increasing the strain-rate from 10-3 to 103 s-1, a moderate strain-rate sensitivity of the uniform and fracture strain, a poor reduction of the cross-sectional area at fracture with increasing the strain-rate were shown. Based on these experimental results the parameters required by the Johnson-Cook constitutive law were determined.

Optimization of Trapezoidal Runner in Plastic Molding Based on MATLAB

2014 ◽  
Vol 552 ◽  
pp. 66-69
Author(s):  
Gui Jie Fan
Keyword(s):  
Obtuse Angle ◽  
Minimum Length ◽  
Special Effects ◽  
Plastic Molding ◽  
Injection Speed ◽  
3D Cad ◽  
Section Area ◽  
Cad Cam ◽  
Mould Design ◽  
Runner Design

The runner design is an important parts in plastic molding design. Its shape and dimensions have special effects on the molten plastic’s pressure, hot loss, injection speed, etc. At present, trapezoidal runner is used widely for better fluidity and lower assembly precision relatively compared with the circular runner. This paper uses the Fminsearch function of MATLAB and constructs an objective function based on the minimum length of the perimeter of the trapezoidal runner to optimize the trapezoidal runner section. The conclusion of this paper is that the perimeter of the trapezoidal runner is the shortest one when a equals c (shown as Fig.1), as well as the obtuse angle between a and c equals 120o. At this conditions, the volume of the molten plastic that flows through the runner section is maximum when the trapezoidal runner section area is given. The optimization results in the plastic mould design can used as the size or the constraints to drive the runner section in 3D CAD/CAM software, which can help the designer to get the trapezoidal runner section easily and quickly.

Composition and Microstructure of Laser Cladding of 316 Stainless Steel

2011 ◽  
Vol 467-469 ◽  
pp. 2054-2059
Author(s):  
Kai Zhang ◽  
Miao Yan Li ◽  
Xin Min Zhang
Keyword(s):  
Stainless Steel ◽  
Laser Cladding ◽  
Layered Manufacturing ◽  
Rapid Manufacturing ◽  
Cad Model ◽  
Laser Metal Deposition ◽  
Post Processing ◽  
316 Stainless Steel ◽  
3D Cad ◽  
Manufacturing Techniques

Laser Metal Deposition Shaping (LMDS) is a Rapid Manufacturing (RM) process that can be classified under the area of layered manufacturing techniques, where parts are built in layers. Parts of any complexity can be built directly from the 3D CAD model without much human intervention and requires minimum post-processing. In fact, LMDS technique can be recognized as multilayer laser cladding. Accordingly, it is necessary to perform the elementary laser cladding experiments with common metal powder so as to better understand the LMDS process. Then the characteristics of microstructure, composition and phase of as-deposited clads were analyzed through SEM and XRD, as well as relative model. The results prove that the microstructure of 316 stainless steel deposits is composed of the slender dendrites growing epitaxially from the substrate, and the composition is uniform without obvious segregation. Besides, it can be deduced from XRD diagram that the microstructure is composed of mono-phase γ.

Binding Performance of a Zirconia Framework Material and Veneering Porcelain

2010 ◽  
Vol 177 ◽  
pp. 186-189 ◽  
Author(s):  
Long Quan Shao ◽  
Bin Deng ◽  
Yuan Fu Yi ◽  
Qi Liu ◽  
Wei Wei Zhang ◽  
...  
Keyword(s):  
Bond Strength ◽  
Thermal Shock ◽  
Shear Bond Strength ◽  
Chemical Element ◽  
Radial Crack ◽  
Visual Observation ◽  
Thermal Shock Test ◽  
Cross Sectional ◽  
Shock Test ◽  
Cad Cam

In this study, the binding performance of a Cercon-based zirconia framework material and special Cercon Ceram S zirconia veneering porcelain is discussed. Rectangular 30 mm × 20 mm × 2 mm porcelain blocks were made from zirconia using the CAD/CAM system. The 2 mm veneering porcelain was then sintered onto blocks at a temperature of 850-800°C with a loading speed of l mm/min. The shear bond strength of the interface was tested. Sintering was studied by visual observation, scanning electron microscopy, energy dispersive spectroscopy (EDS), thermal shock test and other methods. Excellent sintering results of the zirconia framework material and veneering porcelain can be achieved. The cross-sectional morphology of the samples, observed by SEM, shows a uniform, fine, and smooth texture for the veneering porcelain, whereas that of the zirconia framework material shows a rough surface with a uniform and compact texture. EDS results indicate that a small amount of A12O3 and SiO2 is present in the zirconia area, and no ZrO2 or Y2O3 is detected in the veneering porcelain area. No interlayer radial crack or flaw is found throughout the entire thermal shock test of the samples at 60-240°C. Thus, the cracking temperature of the samples is pegged at T>240°C. The shear bond strength of the interface is 32.62±5.77 MPa. Chemical element infiltration exists between zirconia and the veneering porcelain, indicating the chemical bond between the two. An excellent match between the Cercon-based zirconia framework and the special veneering porcelain can be achieved, which can satisfy clinical requirements.

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