Using Simulation to Improve the Quality of the Metallic Industrial Components Made by Rapid Casting

2015 ◽  
Vol 808 ◽  
pp. 187-192
Author(s):  
Alina Popan ◽  
Nicolae Bâlc ◽  
Alexandru Popan ◽  
Nicolae Panc ◽  
Cristina Stefana Borzan
Keyword(s):  
Surface Defects ◽  
Casting Process ◽  
Complex Geometries ◽  
Thin Sections ◽  
Vacuum Casting ◽  
Rapid Casting ◽  
Casting Technology ◽  
Small Series ◽  
Complex Shapes

Industrial parts with complex shapes are characterized by thin sections and complex geometries. Rapid vacuum casting is an ideal technology to manufacture complicated parts in small series production or prototypes. Contributions regarding simulation and analyzing of the parts made by rapid vacuum casting technology are presented in this study. Using dedicated software for simulating the casting process was analyzed and optimized the time of casting, the complete filling with material and also reducing the surface defects.

THE INFLUENCE OF ADDITIVE TECHNOLOGY ON THE QUALITY OF THE SURFACE LAYER AND THE STRENGTH STRUCTURE OF PROSTHETIC CROWNS

Tribologia ◽  
2018 ◽  
Vol 280 (4) ◽  
pp. 13-22
Author(s):  
Łukasz BOJKO ◽  
Wojciech RYNIEWICZ ◽  
Anna M. RYNIEWICZ ◽  
Marcin KOT ◽  
Paweł PAŁKA
Keyword(s):  
Surface Layer ◽  
Layer Structure ◽  
Casting Process ◽  
Additive Technology ◽  
Cocrmo Alloy ◽  
Casting Technology ◽  
Stomatognathic System ◽  
Cad Cam ◽  
Hard Structures

Prosthetic crowns reproduce the damaged hard structures of the patient’s own teeth and take over their natural functions, thus securing the correct reconstruction of the stomatognathic system. The aim is to evaluate the crowns for premolars and molars produced by casting, milling, and Selective Laser Melting technologies, in terms of the accuracy of reproducing the degree against the prosthetic pillar, the analysis of the surface layer structure of the step, and the micromechanical parameters of the alloy. The study material included CoCrMo alloy crowns. The conducted study allowed finding that the tightness of prosthetic crowns made using traditional casting technology as well as in SLM milling and technology is comparable and meets clinical requirements. Structural crown analyses confirmed the very good quality of the surface layer obtained with milling technology and SLM technology using the CAD/CAM method. SLM and digital milling allow the formation of precise and durable structures constituting the foundation of crowns in a time much shorter than the casting process.

scholarly journals Comparison of different additive manufacturing patterns on the performance of rapid vacuum casting for mating parts via the Taguchi method

2020 ◽  
Vol 14 (1) ◽  
pp. 6417-6429 ◽  
Author(s):  
Nur Nabilah Mohd Mustafa ◽  
Aini Zuhra Abdul Kadir ◽  
N. H. Akhmal Ngadiman ◽  
A. Ma'aram ◽  
K. Zakaria
Keyword(s):  
Additive Manufacturing ◽  
Taguchi Method ◽  
Surface Finish ◽  
Fused Deposition Modeling ◽  
Dimensional Accuracy ◽  
Casting Process ◽  
Vacuum Casting ◽  
Fused Deposition ◽  
Small Series ◽  
Master Pattern

Rapid vacuum casting has been proven to be a successful method in producing high-quality parts in small series. However, a challenge lies in the selection of proper Additive Manufacturing (AM) technologies for the development of a master pattern for the vacuum casting process. Each AM technologies differ from one another in terms of dimensional accuracy, surface finish, cost and lead times. The aim of this study is to investigate the performance of casting mating parts based on different additive manufacturing patterns for small batch. Three types of AM-based patterns: Fused Deposition Modeling (FDM), Stereolithography (SLA) and Multi-Jet Fusion (MJF) were compared. The Taguchi method, Signal to Noise ratio (S/N), Analysis of Variance (ANOVA) and T-test were conducted in determining the optimized parameters. From the findings, curing time is shown to be a significant parameter for dimensional accuracy and surface finish. Dimensional deviation varies in different directions of parts. For surface finish, there was only a slight change from the master pattern whereas the surface roughness of casting parts decreased within the range 0.23% to 2.85%. Tolerance grades for the selected dimensions of the parts were in the permissible range, based on ISO286-1:2010. When using distinct kinds of AM patterns to create replacement components, design tolerance is needed. It was suggested to select AM technology similar to that had been used for the original components.  Battery cover was selected as a case study to represent the mating application parts.

Research on Horizontal Electromagnetic Continuous Casting of Sn-P Bronze Strips

2007 ◽  
Vol 26-28 ◽  
pp. 377-380
Author(s):  
Chun Hua Hui ◽  
Ting Ju Li ◽  
Wen Zhong Jin
Keyword(s):  
Electromagnetic Field ◽  
Continuous Casting ◽  
Casting Process ◽  
Optical Microscope ◽  
Shrinkage Cavity ◽  
Casting Technology ◽  
Graphite Mold ◽  
Electromagnetic Continuous Casting ◽  
A Current

In order to improve the quality of tin-phosphor bronze strips, the horizontal electromagnetic continuous casting technology, i.e. imposing alternating electromagnetic field to the horizontal continuous casting process of tin-phosphor bronze strips was developed. The effect of electromagnetic field on the quality of tin-phosphor bronze strips was studied with electron probe microanalysis (EPMA) and optical microscope. The results showed that when the alternating electromagnetic field with 50 Hz frequency and 18 A current was imposed, the crystal grain of the tin-phosphor bronze strips was obviously refined and the segregation and shrinkage cavity were greatly reduced. The quality of tin-phosphor bronze strips was remarkably improved, so the annealing time was shortened from 7 hours to 5 hours, and the service life of graphite mold was extended from 168 hours to 334 hours.

scholarly journals STUDY OF THE THERMAL EXPANSION COEFFICIENT OF SEVERAL SAND MIXTURES USED IN THE CASTING TECHNOLOGY: دراسة معامل التمدد الحراري لعدة خلائط من الرمال المستخدمة في تقنية الصب

2021 ◽  
Vol 5 (4) ◽  
pp. 127-108
Author(s):  
Abbad Nofal Kassouha, Raeed Solyman Muhammad, Moustafa Hussi Abbad Nofal Kassouha, Raeed Solyman Muhammad, Moustafa Hussi
Keyword(s):  
Thermal Expansion ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Casting Process ◽  
Mold Design ◽  
Sand Mixture ◽  
Casting Technology ◽  
Permissible Range ◽  
Wide Range ◽  
Complex Shapes

The casting technology is one of the most important production processes, because of its special characteristics and features such as the ability to produce complex shapes and a wide range of compositions. This work aims to study several mixtures of sand with different structures in terms of permeability, strength, thermal expansion coefficient, comparing them, study the effect of the elements involved in the composition of these mixtures on those parameters, and create a database that can be used both in modeling processes or mold design, as when designing the sand mold The value of the sand expansion of the mold must be taken into account, otherwise the designer will face the problem of the possibility of exit some dimensions of the final product from the permissible range and thus rejecting the product, Or the product is undergone to deformations resulting from the expansion of mold sands, which must be avoided when designing the mold Knowing the characteristics of those sand mixtures helps the investor in choosing the most appropriate mixture for the required casting process in terms of engineering specifications or quantity, with the aim of less costly production by saving in choosing the most appropriate and least expensive sand mixture that serves the desired purpose.

scholarly journals Possibility for Replicating Mechanoscopic Surface Marks in the Hybrid Vacuum-Pressure Casting Process

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 874
Author(s):  
Mariusz Frankiewicz ◽  
Karol Kobiela ◽  
Tomasz Kurzynowski
Keyword(s):  
Geometrical Structure ◽  
Casting Process ◽  
Polymer Materials ◽  
Vacuum Pressure ◽  
Pressure Casting ◽  
Main Research ◽  
Casting Technology ◽  
The Individual ◽  
Cast Parts

Vacuum-pressure casting technology allows small batches of components to be manufactured from polymer materials, mainly from thermosetting plastics such as polyurethane and epoxy resins. Apart from being very simple, the process is also advantageous in that it offers a very accurately reproduced geometrical structure of the surfaces of master patterns used in mold manufacturing. This article presents the results of analyses performed for the process of replicating mechanoscopic marks with the use of three vacuum casting variants, including a hybrid vacuum-pressure casting process developed in particular for the replication purposes. The main research objective was to analyze and evaluate the influence of the parameters of the individual process variants on the quality of the obtained cast parts and on the replication accuracy without introducing additional artifacts on their surfaces. The article discusses the individual stages of the process and provides an analysis of their parameters. The replicas were evaluated for their porosity and reproduction quality with the use of CT methods and comparative photographs obtained from a light microscope.

Numerical Study of Vacuum Casting DVD Panel Based on Silicon Mould

2010 ◽  
Vol 43 ◽  
pp. 707-711
Author(s):  
J. Yang ◽  
L. Xiao ◽  
Jian Zhong Zhou ◽  
Shu Huang ◽  
J.R. Fan ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Numerical Study ◽  
Polymer Melt ◽  
Casting Process ◽  
Processing Parameters ◽  
Mould Temperature ◽  
Melt Temperature ◽  
Vacuum Casting ◽  
Study Process

As a new fabrication technique based on rapid prototyping, vacuum casting process can be especially used in the stage of products development. In this paper, a self-designed and made silicone mould was used to study process of vacuum casting panel part. ProCAST software was adopted to analyze the melt flowing behavior and effects of processing parameters. The key vacuum casting parameters, such as mould temperature, melt temperature, degree of vacuum and coefficient of heat transfer, on the effects of the filling rate of polymer melt were emphasized to be numerical studied. The results indicate that mould temperature and coefficient of heat transfer have the most important influence on quality of the formed panel.

Optimization of Process Parameters for Vacuum Casting Micro-Gear

2011 ◽  
Vol 464 ◽  
pp. 698-702
Author(s):  
Y.C. Dai ◽  
Jian Zhong Zhou ◽  
Shu Huang ◽  
J. Guo ◽  
L. Xiao
Keyword(s):  
Process Parameters ◽  
Dimensional Accuracy ◽  
Casting Process ◽  
Vacuum Casting ◽  
Optimization Of Process Parameters ◽  
Micro Parts ◽  
Master Pattern ◽  
Micro Features ◽  
Silicone Mould

A silicone mould fabrication technique based on vacuum casting was developed and its reproducibility was demonstrated. Orthogonal DOE method was adopted to analyze the effects of vacuum casting process parameters, and the process parameters that had an influence on the quality of the micro-mould cavities were identified and optimized. Micro-casting experiments were carried out using the optimized process parameters and the replicated micro-gears were obtained, these silicone copies were subjected to thorough analysis for dimensional accuracy against the master pattern. The results showed that the fabricated micro-mould was capable of producing functional micro-parts that were able to replicate micro-features, and micro-gears were successfully transferred from the silicone rubber moulds into PU resin pieces under vacuum conditions.

Characterization of homoepitaxial diamond films by Electron microscopy

1991 ◽  
Vol 49 ◽  
pp. 880-881
Author(s):  
D.P. Malta ◽  
S.A. Willard ◽  
R.A. Rudder ◽  
G.C. Hudson ◽  
J.B. Posthill ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Surface Defects ◽  
Substrate Surface ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Large Degree ◽  
Rf Plasma ◽  
Semiconducting Diamond

Semiconducting diamond films have the potential for use as a material in which to build active electronic devices capable of operating at high temperatures or in high radiation environments. A major goal of current device-related diamond research is to achieve a high quality epitaxial film on an inexpensive, readily available, non-native substrate. One step in the process of achieving this goal is understanding the nucleation and growth processes of diamond films on diamond substrates. Electron microscopy has already proven invaluable for assessing polycrystalline diamond films grown on nonnative surfaces.The quality of the grown diamond film depends on several factors, one of which is the quality of the diamond substrate. Substrates commercially available today have often been found to have scratched surfaces resulting from the polishing process (Fig. 1a). Electron beam-induced current (EBIC) imaging shows that electrically active sub-surface defects can be present to a large degree (Fig. 1c). Growth of homoepitaxial diamond films by rf plasma-enhanced chemical vapor deposition (PECVD) has been found to planarize the scratched substrate surface (Fig. 1b).

OPTIMISATION OF SAND CASTING PROCESS FOR IMPELLER USING TAGUCHI METHODOLOGY

2020 ◽  
Vol XVII (2) ◽  
pp. 23-33
Author(s):  
Faisal Hafeez ◽  
Salman Hussain ◽  
Wasim Ahmad ◽  
Mirza Jahanzaib
Keyword(s):  
Surface Roughness ◽  
Surface Defects ◽  
A356 Alloy ◽  
Casting Process ◽  
Sand Casting ◽  
Gate Length ◽  
Taguchi Methodology ◽  
Confirmatory Tests ◽  
Binder Ratio ◽  
Response Measures

This paper presents the study to investigate the effects of binder ratio, in-gate length and pouring height on hardness, surface roughness and casting defects of sand casting process. Taguchi methodology with L9 orthogonal array was employed to design the experimentation. Sand casting of six blade impeller using A356 alloy was performed and empirical models for all the above response measures were formulated. Confirmatory tests and analysis of variance results confirmed the accuracy of the model. Binder ratio was found to be the most significant parameter affecting casting surface defects and surface roughness. This was followed by pouring height and in-gate length.

DIAGNOSING QUALITY OF FRICTION SYSTEMS OF MECHANISMS OF DEVICES

2019 ◽  
Vol 1 (7) ◽  
pp. 10-13
Author(s):  
D. Yu. Ershov ◽  
I. N. Lukyanenko ◽  
E. E. Aman
Keyword(s):  
Surface Defects ◽  
Diagnostic Methods ◽  
Design Parameters ◽  
Diagnostic Model ◽  
Mechanical Assemblies ◽  
Local Defects ◽  
Relationship Of ◽  
The Relationship ◽  
Production And Operation

The article shows the need to develop diagnostic methods for monitoring the quality of lubrication systems, which makes it possible to study the dynamic processes of contacting elements of the friction systems of instrument mechanisms, taking into account roughness parameters, the presence of local surface defects of elements and the bearing capacity of a lubricant. In the present article, a modern diagnostic model has been developed to control the quality of the processes of production and operation of friction systems of instrument assemblies. With the help of the developed model, it becomes possible to establish the relationship of diagnostic and design parameters of the mechanical system, as well as the appearance of possible local defects and lubricant state, which characterize the quality of friction systems used in many mechanical assemblies of the mechanisms of devices. The research results are shown in the form of nomograms to assess the defects of the elements of friction mechanisms of the mechanisms of the devices.

Sign in / Sign up

Export Citation Format

Share Document