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Polycarbonate, a polymer having extremely useful properties, was incorporated in linseed and DCO alkyds of various oil lengths. Compatibility of polycarbonate and alkyds has been investigated. It was found that though polycarbonate was compatible with glyceryl phthalate, it was not compatible with alkyds (oil modified) in general. However, small amounts (4 to 10%) of the polycarbonate could be successfully blended with alkyds particularly with the short oil alkyds. Film properties of these blends were examined and compared with plain alkyds and epoxy modified alkyds in order to determine the usefulness of the polycarbonate‐alkyd blends. It was found that polycarbonate modified alkyds, even with such a small amount of polycarbonate, were superior in film characteristics to both the plain as well as epoxy modified alkyds.

The purpose of this paper is to investigate the effect of layer orientation on the tensile, flexural and fracture behavior of additively manufactured (AM) polycarbonate (PC) produced using fused deposition modeling (FDM).

An experimental approach is undertaken and a total number of 48 tests are conducted. Two types of tensile specimens are used and their mechanical behavior and fracture surfaces are studied. Also, circular parts with different layer orientations are printed and two semi-circular bending (SCB) samples are extracted from each part. Finally, the results of samples with different build directions are compared to one another to better understand the mechanical behavior of additively manufactured PC.

The results demonstrate anisotropy in the tensile, flexural and fracture behavior of the additively manufactured PC parts with the latter being less anisotropic compared to the first two. It is also demonstrated that the anisotropy of the elastic modulus is small and can be neglected. Tensile strength ranges from 40 MPa to 53 MPa. At the end, mode I fracture toughness prediction curves are provided for different directions of the FDM samples. Fracture toughness ranges from 1.93 to 2.37 MPa.mm^1/2.

The SCB specimen, a very suitable geometry for characterizing anisotropic materials, was used to characterize FDM parts for the first time. Also, the fracture properties of the AM PC have not been studied by the researchers in the past. Therefore, fracture toughness prediction curves are presented for this anisotropic material. These curves can be very suitable for designing parts that are going to be produced by 3D printing. Moreover, the effect of the area to perimeter ratio on the tensile properties of the printed parts is investigated.

Pressing problems in optical‐disc manufacture need to be quickly and precisely identified.

Limitations in space and city planning constraints have led to the search for alternative shock mitigation devices that are architecturally appealing. The purpose of this paper is to consider a compromise solution which consists of partially open, thick, bending-resistant shapes made of acrylic material that may be Kevlar- or steel-reinforced. Seven different configurations were analyzed numerically.

For the flow solver, the FEM-FCT scheme as implemented in FEFLO is used. The flowfields are initialized from the output of highly detailed 1-D (spherically symmetric) runs. Peak pressure and impulse are stored and compared. In total, seven different configurations were analyzed numerically.

It is found that for some of these, the maximum pressure is comparable to usual, closed walls, and the maximum impulse approximately 50 percent higher. This would indicate that such designs offer a blast mitigation device eminently suitable for built-up city environments.

Future work will consider fully coupled fluid-structure runs for the more appealing designs, in order to assess whether such devices can be manufactured from commonly available materials such as acrylics or other poly-carbonates.

This would indicate that such designs offer a blast mitigation device eminently suitable for built-up city environments.

This is the first time such a semi-open blastwall approach has been tried and analyzed.

POLYCARBONATE can now be considered among the select group of aircraft transparent plastics and it has several key properties that make it attractive to the aircraft designer particularly because of its impact resistance and good strength at elevated temperatures, raw material suppliers and other manufacturers have struggled to overcome the chemical and physical shortcomings of this material. Optics have been improved both in a ‘cleaning‐up’ of raw resin and the extrusion proces‐sing, and also through optical flattening by pressure polishing of the surfaces. By this latter means, thicknesses greater than the normal sheet extrusion capacity can be built up from thinner gauges by simply welding them together without the use of adhesives or solvents. To summarise: Major Advantages:

A low cost single‐turn conductive plastic trimming and precision potentiometer 138 is available in 1 5/16 in. diameter and covers a resistance range from 1K ohm to 100K ohms. Elements are screened on but can be co‐moulded. It has a centre tap facility and continuous rotation and mechanical stops as standard. Power rating at 40°C ambient is 2W.

Polycarbonate was incorporated in castor oil and nigerseed oil alkyds of various oil lengths. Compatibility of polycarbonate with these alkyds was investigated. It was found that only a small amount (4 to 10%) of polycarbonate could successfully be blended with these alkyds. Film properties of these blends were examined and compared with those of amino alkyd blends, in order to determine the usefulness of the polycarbonate alkyd blends. It was observed that polycarbonate modified alkyds, even with a small amount of polycarbonate were superior in film properties as compared to amino modified alkyds, especially with respect to chemicals and physical properties.

An American company has achieved what is claimed to be a breakthrough of great significance to polymer science.

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.

Carrs Paints of Birmingham have been associated with paints for automobiles for 60 years. They are situated on the door step of the giant Austin Rover plant at Longbridge and they therefore consider themselves to be an integral part of the automotive industry.