bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analytical and Numerical Study of Hard Rock Cutting With Roller Disc Cutters
Authors: Serati Mehdi , Alehossein Habib , Williams David J. 
Published: October 2013

Steel roller discs are an efficient mechanical tool for cutting soft to medium strength rocks in both civil and mining projects. However, their application for hard rock cutting has been hindered since steel discs wear quickly and fail prematurely due to high concentrated stresses generated at the sharp corners and thin elements of the disc. To overcome this problem, the current generation roller discs comprises a steel shaft connected to a tungsten carbide (WC) disc. In other words, while the material of the disc itself is replaced by a stronger WC material, steel continues to be used for the shaft body.
In this paper, to comprehend the influence of material parameters on the induced stresses inside different parts of a roller cutter, an analytical closed-form solution and a series of finite element (FEM) numerical studies are performed. By considering the problem as a traction boundary-value problem in an elastic domain, the analytical solution is based on the Airy stress formulation in Cartesian coordinates with a Fourier series representing the boundary conditions. The analytical result is developed for both plane stress and plane strain conditions, encompassing all possible loading configurations and shaft geometries. To verify the numerical models, these results are also compared with laboratory experimental data obtained from cutting granite using mini discs for the penetration range 1 to 3 mm.
Hydrothermal Ageing Mechanism of Natural Fiber Reinforced Composite in Hot Water
Authors: Liao Mengyuan , Yang Yuqiu , Yu Ying , Hamada Hiroyuki 
Published: October 2013

As well known, sustainability issues represented by the environment and resource protection have been paid close attention nowadays. Natural fiber has been an increasing interest and promising as reinforcing fiber in polymeric composites due to its low density, cost, acceptable specific strength and biodegradation. Even though, the principle challenge for natural fibers used as reinforcement is their internal strong water-absorption ability when the exposed in wet and water environment.
Long-term hydrothermal degradation behavior of Glass reinforced composite (GFRP) and jute reinforced composite (JFRP) have been discussed in previous study on the basis of the great amount of physical and mechanical testing results. As former working reported, gained water content increases linearly against the square root of aging time followed by gradual increase trend in longer duration both in JFRP and GFRP. In particularly, JFRP’s weight loss performance occurred earlier with higher value compared to GFRP. However, water absorption and weight loss mechanism, relationship between weight change and retention of mechanical property for JFRP didn’t report and illustrate clearly and extensively. Therefore, in order to figure it out comprehensively, the current study was focus on hydrothermal ageing mechanism and corresponding degraded mechanical behavior.
Firstly, 2 layers of deeply dried and natural dried jute woven fabric reinforced unsaturated polyester were fabricated by hand-layup method. The cut samples were immersed into 80°C hot water bath for predetermined durations and inspected by ultrasonic wave. Afterwards, 3-point bending test with acoustic emission (AE) measurement was carried out for aged samples. The weight change mechanism, evolution of internal deterioration and mechanical property along with ageing time was investigated. The result indicated that JFRP can absorb water easily and quickly compared with GFRP owing to jute fiber’s hydroscopic nature. Weight loss was caused as a result of resin particle loss and pectin dissolution from the developed micro-crack owing to hydrothermal water environment. What’s more, internal serious deterioration occurred after 24 hours immersion leading to larger reduction of mechanical property.
A KBE Design Methodology to Support Li-Ion Battery Cooling for Hybrid and Electric Vehicles
Authors: Landi Daniele , Cicconi Paolo , Germani Michele 
Published: October 2013

In a scenario of a small and customized production of Electric Vehicles, it is important to have methodologies and tools able to guarantee high flexibility, good quality, and reduced time to market. The optimisation of electric motors and battery design stages is a key factor to achieve the expected results. Specific activities such as design automation, virtual prototyping and simulation are fundamental to obtain high-performance customised solutions. In this context the study of cooling systems for Li-Ion battery packs is one of the most important problems regarding EV and PHEV powertrain design.
The proposed research presents a Knowledge Based methodology to support the cooling design of a battery pack and an analytical tool to evaluate the temperature and heat generation due to electrochemical reactions. All the research project is finalized to a definition of a Knowledge Based System to define a battery layout including engineering knowledge. The current strategies of battery pack design depend on the market size. In particular, the research activity is focalized on customized production of a SME (Small Medium Enterprise).
The main question concerns the estimation of heat generated from electrochemical reactions in a single battery cell. In order to achieve these objectives, a preliminary phase for knowledge acquisition is necessary and a process of formalization has been carried out using the Knowledge Management methods. A first prototype of the Knowledge Based Engineering tool has been developed to determine the optimal cooling condition of a battery pack. The main module is based on an analytical approach which has been formulated to evaluate the average thermal flow generated by a standard LiFePO4 polymeric cell at different values of current and state of charge (SOC). This method can be used for different types of geometry and different chemical compositions. Finally, the proposed approach has been validated by experimental measures and numerical simulations in collaboration with a medium enterprise of electric energy storage systems and light ecological vehicles.
Microdrilling of Biocompatible Materials
Authors: Mohanty Sankalp , Wells Stephen , Hung Wayne 
Published: October 2013

Product miniaturization trend is inevitable. The needs for minimum invasive surgery, smaller sensors for smart machinery, packing more features on a product… require mass production of smaller components from engineering materials. Fabrication of microcomponents requires knowledge of micromachining to avoid costly tool failure and part damage. This research investigates microdrilling of commercially pure titanium, nickel titanium (Nitinol), and 316L stainless steel.
A surface was polished and drilled in rows of ten holes. Through hole drilling at 6:1 aspect ratio was performed on NiTi sheets while blind holes were drilled at 10:1 aspect ratio on Ti or 316L blocks. Microdrills with 100–150 μm diameter and 1.5–3.5 mm flute length were utilized up to 50,000 rpm in minimum quantity lubrication. Finite element models were developed to find upper limits of drilling parameters. Flank wear of 15μm on fine grained WC-Co uncoated tools and peeling of coating layer were used as tool life criteria. Scanning electron microscopy was used to observed tool failure mechanism. Tool life modeling and hole quality were performed to evaluate and compare tool performance.
Although successfully drilling all materials at 10:1 aspect ratio, excessive built-up-edge (BUE) was found on microdrills at all drilling parameters. Such BUE effectively blunted the drill tips and caused drill wandering, degraded hole quality due to rubbing against the drilled wall, work-hardened the drilled surface and accelerated drill wear, and formed burrs at both entrance and exit ends. Wear of a microdrill at the outer corner was more pronounced when drilling CP titanium, but attrition wear at chisel edge was more significant for 316L stainless steel. The classical Taylor equation for macromachining was applicable in microdrilling to rank tool performance and machinability of tested materials. For the same cutting speed of 20 m/min and comparable drilling distance of about 35 mm, CP titanium can be microdrilled 400% faster than 316L stainless steel when applying 0.1 μm/flute chip load for the former and 0.02 μm/flute for the latter. The AlTiN coated drills improved tool life by at least 120%. This coating reduced BUE, drastically improved hole position accuracy by 115%, and decreased hole diameter variation from 0.110% to 0.003% for each mm of drilling distance.
Optimization of Failure Rate of Centrifugal Pumps Using Genetic Algorithm
Authors: Makarachi Peymaan , Pourgol-Mohammad Mohammad 
Published: October 2013

Centrifugal pumps are the most common type of kinetic pumps, and are used most often in applications with moderate to high flow and low head. In order to increase the reliability of the pumps, researches have been conducted on pump design and maintenance approaches in recent years in order to reduce their failure rates. In this article, Genetic Algorithm (GA) is used to find the optimum value for the total failure rate of a centrifugal pump. The total failure rate of the pump is modeled here as a combination of the failure rates of its individual components such as pump seals, shaft, bearings, casing and fluid driver ( by a weakest link model).
Considering that all failure modes are statistically independent and any component failure breaks down the pump, the pump total failure rate is the sum of the components’ failure rates. The failure rate function of seals, shaft, bearings, casing, and fluid driver components which are given in [1], are used as objective functions in the optimization problem. Finally, the optimized parameters and failure rate value of the pump’s specific components are obtained.
Study on the Degradation Mechanism of the Urushi Products
Authors: Shimode Yutaro , Endo Atsushi , Narita Chieko , Higashi Seiji , Murakami Masuo , Takai Yuka , Yasunaga Hidekazu , Goto Akihiko , Hamada Hiroyuki 
Published: October 2013

Japanese lacquer is called “Urushi” in Japanese. Urushi have meanings such as Urushi tree, its resin and also Urushi crafts. Urushi has been used 9000 years ago in Japan. In this long history, Urushi crafts techniques have been developed, refined and inherited by many Urushi craftspeople. As a result, Urushi affect Japanese culture and aesthetic feeling greatly.
Urushi has various characteristics. For example, Urushi coating surface is very smooth and glossy. And more, Urushi is strong to acid and alkali. However it is very weak to ultraviolet rays. As a result, Urushi coating is degraded very quickly in sunlight.
In this study, 6 specimens were prepared by painting 6 kinds of Urushi resins on PMMA (polymethylmethacrylate) boards. Weathering tests of these 6 specimens were done to clarify the degradation of Urushi coating. Additionally, L* value (Brightness), C* value (Chroma) were also measured by spectrophotometric colorimeter to investigate the influence of the degradation on the optical characteristics. Both L* value and C* value were increased after weathering test in most specimens. Glossiness values of specimens were measured by gloss checker. As a result, glossiness values were decreased after weathering test in most specimens.
There was a difference in advance of degradation according to the kind of Urushi. Then when Urushi is used, there are necessities of proper use and change of refining method for Urushi.
Post-Fire Mechanical Properties and Hardness of 5083 and 6082 Aluminum Alloys
Authors: Summers P. T. , Matulich R. D. , Case Scott W. , Lattimer Brian 
Published: October 2013

Aluminum alloys are being increasingly used in lightweight transportation applications such as naval vessels and passenger rail. The primary aluminum alloys considered are Al-Mg (5xxx) and Al-Mg-Si (6xxx) due to their mechanical strength, corrosion resistance, and weldability. A major concern in the use of aluminum alloys for lightweight structural applications is fire exposure. Aluminum mechanical properties begin to significantly degrade at temperatures above 300°C. After fire exposure, structural integrity will be governed by the residual, post-fire strength of the aluminum. However, scarce data is available regarding the post-fire mechanical response.
The post-fire mechanical properties were characterized for several aluminum alloys: 5083-H116, 6082-T651 plate, and 6082-T6 extrusion. The alloys were exposed to elevated temperatures in a furnace to simulate a fire environment. Tension tests were performed to determine the mechanical response of the alloys. Vickers hardness measurements were also performed on specimens exposed for varying durations and temperatures to quantify the time and temperature-dependent behavior. The observed behaviors were explained in relation to the microstructural strengthening mechanisms for each alloy. Correlations were developed between the mechanical properties and Vickers hardness indentations.
Skill Level Differences of Urushi Craftspeople in Urushi Products
Authors: Shimode Yutaro , Endo Atsushi , Narita Chieko , Takai Yuka , Goto Akihiko , Hamada Hiroyuki 
Published: October 2013

There are various traditional crafts in Japan. Japanese modern manufacturing industries have stemmed from the traditional crafts. And there is craftspeople’s wisdom in the traditional crafts technique inherited for years, which is well known as “tacit knowledge”. Especially in Kyoto which has 1200 years history, many traditional crafts have been inherited. In this study, Urushi crafts was focused.
Japanese lacquer is called “Urushi” in Japanese. Urushi have meanings such as Urushi tree, its resin and also Urushi crafts. Urushi has been used 9000 years ago in Japan. In this long history, Urushi crafts techniques have been developed, refined and inherited by many Urushi craftspeople. As a result, Urushi affect Japanese culture and aesthetic feeling greatly. Urushi has been viewed as special, and admired as black with the highest grade. Therefore, the Japanese word “Shikkoku” has been generated, inhere, “Shi” means Urushi, and “Kkoku” means black color.
Urushi has various characteristics. For example, Urushi coating surface is very smooth and glossy. It is considered that these characteristics are influenced by skill level of craftspeople. Then this study aims to analyze a difference between expert craftspeople and non-expert craftspeople in the painting process of Urushi. Body and eye motion between expert and non-expert craftspeople were analyzed and compared. As a result, there were differences in the time of painting with brush. And more there were differences in eye movement. It is considered that these differences were due to the difference of skill level, and in turn, the quality of Urushi products has been influenced.
Design and Rapid Fabrication of Customised Ear Prosthesis: A Case Study in Biomedical Engineering
Authors: Medellín Castillo Hugo I. , Méndez Ruiz Verónica 
Published: October 2013

There are different methods to fabricate a facial prosthesis; the most common is the craftsmanship technique, which depends on the time, experience and skill of the surgeon. Although effective, it is an expensive method in terms of time and cost, and the precision of the prosthesis is limited to the manual sculpting skill of the surgeon. However, modern design and manufacturing technologies in engineering are increasingly being used in biomedical engineering applications such as prosthesis and implant design, surgical planning and tissue engineering. These modern engineering technologies have led to the enhancement of traditional medical methods in terms of accuracy, time, cost, resources and safety.
In order to enhance the conventional craftsmanship technique used in the fabrication of facial prosthesis, this paper presents a new approach to design and manufacture customized ear prosthesis based on Reverse Engineering (RE) and Rapid Prototyping (RP) technologies. A case study is introduced and developed along paper. The ear prosthesis is designed using RE and Computer Aided Design (CAD). Fabrication of the prosthesis is carried out by RP and lost-wax casting. The results are presented and compared with the traditional craftsmanship technique. Advantages and disadvantages of using modern design and manufacture engineering techniques are identified and discussed.
Comparison of Closed Chain Mechanisms for Positional Deviations
Authors: Jawale H. P. , Thorat H. T. 
Published: October 2013

Closed Chain Mechanisms are popular in Automation Technology for transmitting motion under specific objective task. Single-Degree of Freedom (DoF) Four-bar chain is basic mechanisms synthesized for such applications. Joint clearances and drive backlash are inevitable in such mechanisms and introduce error in coupler positions while accomplishing the task.
The present paper considers effect of joint clearances and drive backlash as error source for coupler positions in single-DoF mechanism. The deviations of desired positions and actual positions are estimated for specific objective task. Further, effect of these error sources is modelled with a higher-DoF mechanism which is kinematically better than single-DoF mechanisms. Two-DoF mechanism is modelled for identical objective task. Maximum positional deviations are estimated for two-DoF mechanism. The comparative analysis of deviation is obtained. Relative maximum positional deviation in both mechanisms is expressed in terms of dimensionless number as measure of performance.
Impact Behavior of Liquid Crystalline Polymers
Authors: Saigal Anil , Ward Dan , Zimmerman Michael A. 
Published: October 2013

Liquid crystalline polymers have the advantage of achieving desirable mechanical properties at a competitive cost. They are composed of molecular chains that are highly oriented and tightly packed at temperatures above and below its melting point. This high degree of orientation has the following advantages: ease of processing, high mechanical strength at extreme temperatures, and resistance to mostly all chemicals, weathering, radiation, and burning.
On the other hand, this high degree of orientation causes liquid crystalline polymers to have low impact strength as well as an uneven amount of shrinkage prior to molding. The objective of this study is to determine the effects of injection-molding parameters on the impact behavior of liquid crystalline polymers, in an attempt to improve and understand the processing of the material. The conditions to be tested are as follows: fill speed, initial mold temperature, and packing pressure.
The impact tester used for this research was an Instron Dynatup tester. Based on the data, it is apparent that fill speed is the greatest determining factor for optimizing the impact energy of the injection-molded liquid crystalline polymers followed by high packing pressure. In addition, even though the nature of the impact energy curves for LCPs and materials such as Delrin are similar, the impact load curves as a function of time are significantly different. This can be attributed to the layered structure of LCP samples.
Modification of the Interface in Carbon Nanotube-Grafted T-Glass Fiber
Authors: Kawada H. , Sato S. , Kameya M. 
Published: October 2013

In recent years, carbon nanotubes (CNTs) have attracted a lot of interest as an additional component in fiber reinforced plastics (FRP) to improve the properties of the fiber/matrix interface. An improvement of the apparent interfacial shear strength (ISS) was achieved by grafting CNTs onto reinforcement fibers instead of dispersing CNTs in the matrix. In one study, composites containing CNT-grafted fibers and epoxy resin demonstrated 26% ISS improvement over the baseline composites. However, few studies are focused on glass fibers, due to their low heat resistance.
In this study, the effects of grafting CNTs onto T-glass fibers were evaluated by investigating the mechanical and interfacial properties of the CNT-grafted fiber/epoxy resin model composites. Elastic shear-lag analysis was also used to investigate the effect of CNTs on ISS.
We used the chemical vapor deposition (CVD) method to graft CNTs onto T-glass fibers. As a result, CNTs were grafted relatively uniformly and cylindrically onto the fibers, which indicates that the CNT-grafting process was appropriate.
The CNT-grafted fiber/epoxy resin model composites showed a significant (46∼67%) increase of interfacial shear strength. The formation of an interfacial region containing CNTs was observed around each fiber. Elastic shear-lag analysis showed a 20% increase of ISS. Those results imply that the elastic modulus of the interfacial region around the fibers was higher than that of epoxy resin.
A Hybrid Metal-to-Composite Joint Fabricated Through Additive Manufacturing Processes
Authors: Whitney Thomas J. , Gibson Thao , Lafdi Khalid , Welk Brian 
Published: October 2013

Devices and machines which perform additive manufacturing (adding material in a layer-wise or bead-wise manner to produce complex structure rather than removing material through machining) are maturing and entering the commercial market. While small prototype parts are routinely made using these devices, a number of industries, including biomedical and aerospace, are considering using these techniques for production parts. New materials which take advantage of the unique capability of additive manufacturing are beginning to evolve. Hybridization of materials at smaller scales now becomes possible with the precision of additive manufacturing devices. However, the fundamentals of structural performance of materials that can be produced by these methods are still to be explored and understood..
The current effort focuses on characterizing and describing the fundamental processing of hybrid materials produced using a combination of laser sintering of metals combined with polymer infusion of advanced carbon fabric. Ultimately, the work seeks to develop a fundamental understanding of the structural mechanics of these novel graphite-metal materials produced through hybrid processes. By understanding development and location of weak structural planes, effects of voids and discontinuities, load transfer from nano to macro scale, reinforcement distribution, gradients in properties, and effects of residual stress, a complete materials design process beginning with structural requirements and ending with material and process selection can be developed.
This paper will summarize the first experimental steps taken to process and fabricate a metal-to-composite hybrid joint using a combination of additive manufacturing and conventional composite processes. Experimental conditions are described and morphology of the resulting hybrids is discussed. Future plans for testing are described.