scholarly journals Variations in the Surface Integrity of Ti-6Al-4V by Combinations of Additive and Subtractive Manufacturing Processes

Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1825 ◽  
Author(s):  
Roland Bejjani ◽  
Erik Bamford ◽  
Stefan Cedergren ◽  
Andreas Archenti ◽  
Amir Rashid

Additive manufacturing (AM) has recently been accorded considerable interest by manufacturers. Many manufacturing industries, amongst others in the aerospace sector, are already using AM parts or are investing in such manufacturing methods. Important material properties, such as microstructures, residual stress, and surface topography, can be affected by AM processes. In addition, a subtractive manufacturing (SM) process, such as machining, is required for finishing certain parts when accurate tolerances are required. This finish machining will subsequently affect the surface integrity and topography of the material. In this research work, we focused on the surface integrity of Ti-6Al-4V parts manufactured using three different types of AM and finished using an SM step. The aim of this study was to gain an understanding on how each process affects the resulting surface integrity of the material. It was found that each AM process affects the materials’ properties differently and that clear differences exist compared to a reference material manufactured using conventional methods. The newly generated surface was investigated after the SM step and each combination of AM/SM resulted in differences in surface integrity. It was found that different AM processes result in different microstructures which in turn affect surface integrity after the SM process.

Author(s):  
C. F. Nwaeche ◽  
A. O. Fagunwa ◽  
A. A. Olokoshe ◽  
A. E. Aderowmu ◽  
V. C. T. Uzondu ◽  
...  

All over the world, additive and subtractive manufacturing are the two basic manufacturing methods used for the development of engineering goods and products. In most cases, the method adopted by the manufacturers usually depends on its cost-effectiveness. However, most of the manufacturing industries in Nigeria have little or no information on the relative advantages and disadvantages of the two methods. This had led to many industries adopting one particular method hook, line and sinker without considering the merits that would be offered by the alternative manufacturing method. This paper, therefore, compared the two methods of manufacturing by carrying out reverse engineering of worn-out helical gears (components of a juice extractor) developed using additive and subtractive manufacturing techniques. The parts of the equipment were developed using a lathe, milling and deburring machines to carry out the drilling, turning, grinding, milling and deburring for subtractive manufacturing and 3-D printing machine for additive method. Two gears A and B were developed by both subtractive and additive methods using the dimension of two old gears, which serve as the basis for determining the variation of the nomenclatures of the developed gears from the standard. The time used for product development, cost of production and the energy expended during the production of the two gears using additive and subtractive manufacturing methods were also determined using appropriate methods. The study also showed that it is less expensive to produce both gears A and B using the additive method than the subtractive method. Similarly, in term of energy used, less energy was used during fabrication of the gears using additive method than subtractive method but in general, when you want to print a whole component at once the 3D printer volume could be a major constraint. Hence, the adaptation of additive manufacturing method as a whole or part with the existing subtractive method will help to improve manufacturing industries in Nigeria.


2020 ◽  
Author(s):  
Sandip Dutta ◽  
Sagar Dasgupta ◽  
Geetha Chimata

Additive manufacturing is the buzz word these days and many companies are leaning on this technology to leap forward in un-chartered design space that promises to give better performance at impossible to reach design goals with the current manufacturing methods. This paper addresses recent developments that have occurred in Energy related businesses with the adoption of 3D printing, also known as Additive Manufacturing (AM). It covers what and why of additive manufacturing; what constitutes energy and AM industry; current activities in AM for energy; AM for different energy sectors; AM processes; AM applications; selected patents in additive manufacturing associated with energy applications; and economic and financial aspects of AM in energy related industries. In this review paper it was noted that in-spite of phenomenal growth in AM, it seldom replaces traditional production methods due to associated constraints. Many companies are finding complimentary AM processes along with subtractive manufacturing techniques to meet the market demands. However, AM is particularly advantageous and attractive compared to traditional manufacturing methods for low volume complex geometry parts.


Author(s):  
Alejandro Pereira ◽  
Alberto Tielas ◽  
Teresa Prado ◽  
Maria Inmaculada Fenollera ◽  
José Antonio Pérez

The need to develop novel lightweight materials and their manufacturing processes is sets out to meet the new aerospace, automotive and construction requirements. Within this context, this research work is proposed to develop a novel thermoplastic composite material with high mechanical properties. These composites will be based on thermoplastic matrixes made from polyamide and 35% short glass fiber filled-polyamide reinforced with different types of fabrics. As reinforcement, glass fiber fabrics will be used as the base. They will be treated with different processes, both chemical and physical, to promote adherence to the matrix. Textile overmoulding technology was selected for manufacturing these composites. This technology was primarily developed to manufacture aesthetic lined components and has achieved a great implantation. Once these new composites are manufactured, they will be submitted to different tests to evaluate their behavior regarding adhesion, impact strength and stiffness. It is expected an improvement on stiffness and impact absorption.


Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 799
Author(s):  
Justyna Miedzianowska ◽  
Marcin Masłowski ◽  
Przemysław Rybiński ◽  
Krzysztof Strzelec

Increasingly, raw materials of natural origin are used as fillers in polymer composites. Such biocomposites have satisfactory properties. To ensure above-average functional properties, modifications of biofillers with other materials are also used. The presented research work aimed to produce and characterize elastomeric materials with a straw-based filler and four different types of montmorillonite. The main research goal was to obtain improved functional parameters of vulcanizates based on natural rubber. A series of composites filled with straw and certain types of modified and unmodified nano-clays in various ratios and amounts were prepared. Then, they were subjected to a series of tests to assess the impact of the hybrids used on the final product. It has been shown that the addition of optimal amounts of biofillers can, inter alia, increase the tensile strength of the composite, improve damping properties, extend the burning time of the material and affect the course of vulcanization or cross-linking density.


Author(s):  
R. PANCHAL ◽  
B. VERMA

Early detection of breast abnormalities remains the primary prevention against breast cancer despite the advances in breast cancer diagnosis and treatment. Presence of mass in breast tissues is highly indicative of breast cancer. The research work presented in this paper investigates the significance of different types of features using proposed neural network based classification technique to classify mass type of breast abnormalities in digital mammograms into malignant and benign. 14 gray level based features, four BI-RADS features, patient age feature and subtlety value feature have been explored using the proposed research methodology to attain maximum classification on test dataset. The proposed research technique attained a 91% testing classification rate with a 100% training classification rate on digital mammograms taken from the DDSM benchmark database.


Author(s):  
Rajkeerthi E ◽  
Hariharan P

Abstract Surface integrity of micro components is a major concern particularly in manufacturing industries as most geometry of the products must meet out necessary surface quality requirements. Advanced machining process like electrochemical micro machining possess the capabilities to machine micro parts with best surface properties exempting them from secondary operations. In this research work, different electrolytes have been employed for producing micro holes in A286 super alloy material to achieve the best surface quality and the measurement of surface roughness and surface integrity to evaluate the machined surface is carried out. The machined micro hole provides detailed information on the geometrical features. A study of parametric analysis meant for controlling surface roughness and improvement of surface integrity has been made to find out the suitable parameters for machining. The suitability of various electrolytes with their dissolution mechanism and the influence of various electrolytes have been thoroughly studied. Among the utilized electrolytes, EG + NaNO3 electrolyte provided the best results in terms of overcut and average surface roughness.


2017 ◽  
Vol 69 (4) ◽  
pp. 612-619 ◽  
Author(s):  
Christian Engelhardt ◽  
Jochen Witzig ◽  
Thomas Tobie ◽  
Karsten Stahl

Purpose Water can alter the performance of modern gear lubricants by influencing the flank load carrying capacity of gears significantly. The purpose of this paper is to investigate the influence of water contaminations in different kinds of base oils on the micro-pitting and wear performance of case carburized gears. Design/methodology/approach Concerning micro-pitting and wear, tests, based mostly on the following standardized tests, are performed on a Forschungsstelle fuer zahnraeder und getriebebau (FZG)-back-to-back gear test rig: micro-pitting short test Graufleckenkurztest (GFKT) according to DGMK 575 (screening test), micro-pitting test Graufleckentest (GT) according to FVA 54/7 (load stage test and endurance test) and Slow-speed wear test according to DGMK 377. To investigate the effect of water on the gear load carrying capacity dependent on different types of base oils, two polyglycol oils (PG1 and PG2), a polyalphaolefin oil, a mineral oil and an ester oil E are used. Each of these oils are common wind turbine gear oils with a viscosity ISO VG-220. Additionally, a manual transmission fluid with a viscosity of society of automotive engineers (SAE) 75W-85 is tested. Findings Considering the micro-pitting and wear performance, a significant decrease caused by water contaminations could not be detected. Regarding pitting damages, a generally negative influence was observed. This influence was differently distinctive for different base oil types. Especially non-polar lubricants seem to be affected negatively. The documented damages of the tooth flanks confirm this observation. While typical pitting damages appeared in test runs with polar lubricants, the disruption in test runs with non-polar lubricants was more extensive. Based on the experimental investigations, a general model of the damaging mechanisms of water contaminations in lubricants was derived. It is split into three partitions: interaction lubricant–water (effect of water on the molecular structure of base oils and additives), chemical-material-technological (especially corrosive reactions) and tribological influence (effect of water droplets in the contact zone). It has to be considered that the additive package of lubricants affects the influence of water contaminations on the flank load carrying capacity distinctively. An influence of water on the micro-pitting and wear performance in other than the given lubricants cannot be excluded. Originality/value While former research work was focused more on the effects of water in mineral oils, investigations concerning different types of base oils as well as different types of damages were carried out within this research project.


Author(s):  
Ivan Molnár ◽  
Ladislav Morovič

Abstract The paper discusses the use of 3D digitization and additive manufacturing technologies in the field of medicine. In addition, applications of the use of 3D digitization and additive manufacturing methods are described, focusing on the design and manufacture of individual medical aids. Subsequently, the process of designing and manufacturing of orthopedic aids using these technologies is described and the advantages of introducing the given technologies into the design and manufacturing processes in the medicine sector are presented.


The purpose of this work is to develop a UJSON web technology with C# application to analyze the student data in real-ime. Execute continuous requests on JSON streaming data based on advanced technologies for parallel streaming computing, suitable for solving analytic problems and calculation of metrics in real-time. The developed management information system in this research work designed to filtering event flow, building an event flow as a query result, grouping and aggregation of events, and creating window semantics. For testing the proposed work, several queries were selected that implement aggregation with different types of semantic windows (Steps, Slides). Testing was done locally and on education moodle clusters. It was used 4 types of configurations 2, 4, 8, and 16 computing nodes. Based on the obtained results, scalability is noticeable with an increase in the number of nodes. The updated functions of the proposed UJSON could improve the construction of parallel flow systems and data processing. The developed approach based on modern and advanced parallel flow technologies for output calculations considering the pros and cons of various approaches found in the current era.


Sign in / Sign up

Export Citation Format

Share Document