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The purpose of this paper is to identify if the implementation of ultrasonic vibration in laser engineered net shaping (LENS) process can help to reduce internal weaknesses such as porosity, coarse primary TiB whisker and heterogeneous distribution of TiB reinforcement in the LENS-fabricated TiB reinforced Ti matrix composites (TiB-TMC) parts.

An experimental investigation is performed to achieve the results for comparative studies under different fabrication conditions through quantitative data analysis. An approach of microstructural characterization and mechanical testing is conducted to obtain the output attributes. In addition, the theoretical analysis of the physics of ultrasonic vibration in the melting materials is presented to explain the influences of ultrasonic vibration on the microstructural evolution occurred in the part fabrication.

Because of the nonlinear effects of acoustic streaming and cavitation induced by ultrasonic vibration, porosity is significantly reduced and a relatively small variation of pore sizes is achieved. Ultrasonic vibration also causes the formation of smaller TiB whiskers that distribute along grain boundaries with a homogeneous dispersion. Additionally, a quasi-continuous network (QCN) microstructure is considerably finer than that produced by LENS process without ultrasonic vibration. The refinements of both reinforcing TiB whiskers and QCN microstructural grains further improve the microhardness of TiB-TMC parts.

The novel ultrasonic vibration-assisted (UV-A) LENS process of TiB-TMC is conducted in this work for the first time to improve the process performance and part quality.

Ultrasonic additive manufacturing (UAM) is a fabrication technology based on ultrasonic metal welding. As a solid-state process, temperatures during UAM fabrication reach a fraction of the melting temperatures of the participating metals. UAM parts can become mechanically compliant during fabrication, which negatively influences the ability of the welder to produce consistent welds. This study aims to evaluate the effect of weld power on weld quality throughout a UAM build, and develop a new power-compensation approach to achieve homogeneous weld quality.

The study utilizes mechanical push-pin testing as a metric of delamination resistance, as well as focused ion beam and scanning electron microscopy to analyze the interface microstructure of UAM parts.

Weld power was found to negatively affect mechanical properties and microstructure. By keeping weld power constant, the delamination energy of UAM coupons was increased 22 per cent along with a consistent grain structure. As a result, to ensure constant properties throughout UAM component construction, maintaining weld power is preferable over the conventional strategy based on amplitude control.

Further characterization could be conducted to evaluate the power control strategy on other material combinations, though this study strongly suggests that the proposed approach should work regardless of the metals being welded.

The proposed power control strategy can be implemented by monitoring and controlling the electrical power supplied to the welder. As such, no additional hardware is required, making the approach both useful and straightforward to implement.

This research paper is the first to recognize and address the negative effect of build compliance on weld power input in UAM. This is also the first paper to correlate measured weld power with the microstructure and mechanical properties of UAM parts.

The effects of ultrasonication on the epoxy resin and its emulsion were investigated to find out the changes in the M_η and molecular structure of epoxy, as well as its room temperature storage stability, centrifugal stability, particle size and its distribution and particle morphology more importantly with the influence of different ultrasonic irradiation time, power and temperature.

The emulsion was prepared using an emulsifier with epoxy resin and by using phase inversion after subjecting to ultrasound irradiation with a power of 200 W at 50°C for 60 min. The changes in the epoxy resin and its emulsion induced by ultrasound were characterized by Ubbelohde viscometer, FT-IR, ¹³C-NMR, high-speed desktop centrifuge, laser particle size analyzer and transmission electron microscope.

The molecular weight of the epoxy resin was initially decreased and then stabilized by the increasing of ultrasonic irradiation time. The mole rate of the epoxy groups in epoxy molecular were decreased by about 14 per cent, resulting from ultrasonic irradiation. The particle size of the emulsion was decreased, while the particle size distribution became uniform in a certain time. The narrow distribution, stable and uniform of waterborne epoxy resin emulsion with more than 60 days room temperature storage period, 80 per cent of the supernatant volume, about 220 nm average particle size was gained with a power of 200 W at 50°C for 60 min.

To overcome the problems commonly encountered with an epoxy emulsion, for example, short storage period and wider particle size, which limit its practical application, the effects of ultrasonic irradiation on the epoxy resin and its emulsion, were investigated. As the stability of emulsion was improved with the introduction of ultrasonic irradiation, the application of epoxy emulsion was improved.

The room temperature storage stability and centrifugal stability of the emulsion were decreased by the mechanical method, and thus, the benefit of an in-depth understanding of the influence of ultrasonic treatment on epoxy resin and its emulsion could further promote the development of water-based coatings.

This review paper reveals the literature on ultrasonic, chemical-assisted ultrasonic and rotary ultrasonic machining (USM) of glass material. The purpose of this review paper is to understand and describe the working principle, mechanism of material removal, experimental investigation, applications and influence of input parameters on machining characteristics. The literature reveals that the ultrasonic machines have been generally preferred for the glass and brittle work materials. Some other non-traditional machining processes may thermally damage the work surface. Through these USM, neither thermal effects nor residual stresses have been generated on the machined surface.

Various input parameters have the significant role in machine performance characteristics. For the optimization of output response, several input parameters have been critically investigated by the various researcher.

Some advance types of glasses such as polycarbonate bulletproof glass, acrylic heat-resistant glass and glass-clad polycarbonate bulletproof glass still need some further investigation because these materials have vast applications in automobile, aerospace and space industries.

Review paper will be beneficial for industrial application and the various young researcher. Paper reveals the detail literature review on traditional ultrasonic, chemical assisted ultrasonic and rotary USM of glass and glass composite materials.

This article aims to propose a new measurement method for ultrasonic power based on self-reciprocity theorem which turns the estimation of ultrasonic power to the measurement of first echo current and open-circuit voltage of the driving source.

The formula for ultrasonic power is derived which has corrected the position of pressure reflection coefficient on the interface of water and steel. The diffraction correction for focusing transducers is evaluated using numerical computation of the Rayleigh integral. One way to estimate the reflection coefficient of focusing beams on heterogeneous interface is also depicted.

Comparison experiment with radiation force balance method demonstrates that ultrasonic power measurement using self-reciprocity is sound in theory and feasible in practice.

It has a better capability of anti-environmental interference and, thus, can be extended to low-level and high-frequency power measurements.

The purpose of this paper is to develop an optimised sonochemical surface modification process which could be operated at low temperature and which uses non‐hazardous chemistry with short treatment times. A range of sonochemical parameters such as ultrasonic intensity/power and process temperature were investigated.

A 20 kHz ultrasonic probe was used as the ultrasonic source. Ultrasound was applied through deionised water (DI) to sonochemically surface modify a high Tg epoxy laminate material (Isola 370 HR). The efficiency of the sonochemical surface modification process was determined by weight loss, roughness, adhesion and scanning electron microscopy (SEM).

This study has confirmed that ultrasound has the ability to surface modify a high Tg epoxy substrate material (Isola 370 HR). Weight loss and roughness values were increased by using an optimised ultrasonic process compared to control samples which were processed under “silent” conditions. Adhesion testing showed an improvement in the adhesion level between the surface and the subsequently electroless plated copper.

Surface modification of high Tg materials generally utilizes wet chemical methods. These processes involve using hazardous chemicals, high temperatures, require high volumes of water for rinsing and need relatively long immersion times. This research has shown that by optimising ultrasonic parameters, surface modification can be brought about in deionised water (DI) at low temperature.

Although wire‐bonding is an established and well‐known technique for micro‐joining on leadframes, direct die‐attach without housing on printed circuit boards has some new requirements for the surface of the bond pads and the PCB itself. The best choice of material for the bond pads is a pure gold metallisation. The quality of the surface can be tested during wire‐bonding using the ultrasonic‐power process window. It will be shown that the surface and the PCB itself have a considerable influence on the ultrasonic and thermosonic bonding process.

This paper aims to comprehensively review ultrasonic additive manufacturing (UAM) process history, technology advancements, application areas and research areas. UAM, a hybrid 3D metal printing technology, uses ultrasonic energy to produce metallurgical bonds between layers of metal foils near room temperature. No melting occurs in the process – it is a solid-state 3D metal printing technology.

The paper is formatted chronologically to help readers better distinguish advancements and changes in the UAM process through the years. Contributions and advancements are summarized by academic or research institution following this chronological format.

This paper summarizes key physics of the process, characterization methods, mechanical properties, past and active research areas, process limitations and application areas.

This paper reviews the UAM process for the first time.

The purpose of this paper is to investigate how to make powered‐wheelchair driving easier using simple expert systems to interpret joystick and ultrasonic sensor data. The expert systems interpret shaky joystick movement and identify potentially hazardous situations and then recommend safe courses of action.

The way that a human user interacts with a powered‐wheelchair is investigated. Some simple expert systems are presented that interpret hand tremor and provide joystick position signals for an ultrasonic sensor system. Results are presented from a series of timed tasks completed by users using a joystick to control a powered‐wheelchair. Effect on the efficiency of driving a powered‐wheelchair is measured using the times to drive through progressively more complicated courses. Drivers completed tests both with and without sensors and the most recently published systems are used to compare results.

The new expert systems consistently out‐performed the most recently published systems. A minor secondary result was that in simple environments, wheelchair drivers tended to perform better without any sensor system to assist them but in more complicated environments then they performed better with the sensor systems.

The time taken for a powered‐wheelchair to move from one place to another partly depends on how a human user interacts with the powered‐wheelchair. Wheelchair driving relies heavily on visual feedback and the experience of the drivers. Although attempts were made to remove variation in skill levels by using sets of data associated with each driver and then using paired statistical tests on those sets, some variation must still be present.

The paper presents new systems that could allow more people to use powered‐wheelchairs and also suggests that the amount of sensor support should be varied depending on circumstances.

The new systems described in the paper consistently performed driving tasks more quickly than the most recently published systems.

The purpose of this paper is to prepare waterborne UV-curable pigment pastes for cotton fabric printing.

O/W (oligomer-in-water) emulsions of polyurethane acrylate (PUA) oligomer in sodium dodecyl benzene sulphonate (SDBS) aqueous solution were prepared by ultrasonic emulsification method.

The present work studies various factors affecting the stability and droplet size of the O/W emulsion stabilised by SDBS. The optimal emulsifier concentration was 2.5 per cent, under which condition the stability of the emulsion increased as the emulsifier content increased, with a subsequent decrease in the droplet size of the emulsion, while above which emulsion agglomeration occurred. Increasing the power and duration of ultrasonic dispersion resulted in increased emulsion stability and decreased droplet size, while increases in the oligomer content reduced the emulsion stability. Darocure 1173 mixed with PUA and then emulsified in the SDBS aqueous solution guaranteed uniform dispersion of the photoinitiator, resulting in faster curing speed.

This paper presents a new method for making waterborne externally emulsified oligomers for UV curing, and finds that it is easy to convert the existing oligomers into waterborne equivalents by this method. Cotton fabrics printed with the oligomer emulsion based pastes were found to have good colour strength and crockfastness.