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This study aims to report the preparation, selective laser sintering (SLS) processing and properties of a new nylon elastomer powder. The effects of solvent, dissolution temperature and time and cooling method and speed on the particle size and morphologies of the prepared nylon elastomer powder are investigated.

The prepared nylon elastomer power possesses the particle size of around 50 mm and is spherical in shape, indicating that this study provides the feasible dissolution-precipitation process, a distillation cooling method and a suitable solvent to prepare nylon elastomer powders.

Compared to pure nylon 12, the nylon elastomer has a lower part bed temperature and a wider sintering window for the SLS process. The wider sintering window indicates the better SLS processibility. The lower part bed temperature is beneficial to the recycling of material and the decrease in the requirement of SLS equipment.

The nylon elastomer in this study has a lower part bed temperature and a wider sintering window for the SLS process. The wider sintering window indicates better SLS processibility. The lower part bed temperature is beneficial to the recycling of material and the decrease in the requirement of SLS equipment.

The purpose of the paper is to present a novel cross-modal sensor whose tactile is computed by the visual information. The proposed sensor can measure the forces of robotic grasping.

The proposed cross-modal tactile sensor consists of a transparent elastomer with markers, a camera, an LED circuit board and supporting structures. The model and performance of the elastomer are analyzed. Then marker recognition method is proposed to determine the movements of the marker on the surface, and the force calculation algorithm is presented to compute the three-dimension force.

Experimental results demonstrate that the proposed tactile sensor can accurately measure robotic grasping forces.

The proposed cross-modal tactile sensor determines the robotic grasping forces by the images of markers. It can give more information of the force than traditional tactile sensors. Meanwhile, the proposed algorithms for forces calculation determine the superior results.

This paper aims to seek to fill a gap in the literature by characterizing the fatigue life and microstructure of a printed elastomer material, the TangoBlackPlus material.

Because the TangoBlackPlus material is marketed as “rubber-like”, the printed elastomer specimens were tested according to the ASTM D4482-11 “Test Method for Rubber Property Extension Cycling Fatigue”. The microstructure of the printed material and multi-material interface was examined by slicing specimens and examining them under an optical microscope.

Findings are developed to show the relationship between elongation and expected fatigue life. Findings also indicate that the smoother, non-support encased “glossy” surface finish option for PolyJet parts improve the fatigue life of components and that there are a number of microscopic voids in the TangoBlackPlus material that seem to be concentrated at layer and print head boundaries.

This paper provides a glimpse into the fatigue properties and microstructure of printed elastomeric parts, a previously unstudied area. This work is limited in that it only looks at specimens created in a single orientation, on a single machine, with a single material. More work is needed to understand the general fatigue properties of printed elastomers and the factors that influence fatigue life in these materials.

The authors provide several design guidelines based on the findings and previous work that can be used to increase the fatigue life of printed elastomer components.

As additive manufacturing (AM) technology moves from a prototyping tool to a tool used to create end use products, it is important to examine the expected lifespan of AM components. This work adds to the understanding of the expected product lifecycle of printed elastomer components that will likely be expected to withstand large repeated loading conditions.

A new extensive and detailed study on the advanced elastomers market in Europe has been published by IAL Consultants Ltd., of 14 Buckingham Palace Road, London SW1W OQP (telephone 01 828 5036).

2. Elastomers A wide variety of elastomers, generally synthetic, are used in modern valves of the butterfly and diaphragm types with the dual function of lining/protecting internal metal surfaces in contact with the duty and providing the necessary interference for sealing. Without resorting to exotic and expensive metals of construction, even most aggressive services can be successfully handled by variation of elastomer type, while the particular compound is designed to still retain the physical characteristics necessary for optimum sealing. The number of permutations is thus large and indeed one manufacturer offers as many as 18 different resilient liner options. The main elastomer types are summarised:

Soft robotics is currently a rapidly growing new field of robotics whereby the robots are fundamentally soft and elastically deformable. Fabrication of soft robots is currently challenging and highly time- and labor-intensive. Recent advancements in three-dimensional (3D) printing of soft materials and multi-materials have become the key to enable direct manufacturing of soft robots with sophisticated designs and functions. Hence, this paper aims to review the current 3D printing processes and materials for soft robotics applications, as well as the potentials of 3D printing technologies on 3D printed soft robotics.

The paper reviews the polymer 3D printing techniques and materials that have been used for the development of soft robotics. Current challenges to adopting 3D printing for soft robotics are also discussed. Next, the potentials of 3D printing technologies and the future outlooks of 3D printed soft robotics are presented.

This paper reviews five different 3D printing techniques and commonly used materials. The advantages and disadvantages of each technique for the soft robotic application are evaluated. The typical designs and geometries used by each technique are also summarized. There is an increasing trend of printing shape memory polymers, as well as multiple materials simultaneously using direct ink writing and material jetting techniques to produce robotics with varying stiffness values that range from intrinsically soft and highly compliant to rigid polymers. Although the recent work is done is still limited to experimentation and prototyping of 3D printed soft robotics, additive manufacturing could ultimately be used for the end-use and production of soft robotics.

The paper provides the current trend of how 3D printing techniques and materials are used particularly in the soft robotics application. The potentials of 3D printing technology on the soft robotic applications and the future outlooks of 3D printed soft robotics are also presented.

Elastomer seals are used in many applications. They are exposed to lubricants and additives at elevated temperatures, as well as mechanical stresses. They can only provide good sealing function when they have resistance to those factors. There are many elastomer-lubricant compatibility tests based on DIN ISO 1817 in industry. However, they are insufficient and costly. Correlations between the tests and the applications are inadequate. The purpose of this study is investigating lubricant compatibility of fluoroelastomers (FKM) seals in polyethylene-glycol (PG)- and polyalphaolefin (PAO)- based synthetic oils and developing a methodology to predict seal service life.

A new compatibility test which is more sufficient in terms of time and cost was developed and compared with a standard test, currently used in industry. Compatibility of FKM radial lip seals with PG- and PAO-based synthetic oils with different additives was investigated chemically and dynamically. Failure mechanisms were examined.

The new method and the Freudenberg Flender Test FB 73 11 008 showed similar results concerning damages and similar tendencies regarding wear. The additive imidazole derivative was the most critical. Static tests give indications of possible chemically active additives, but alone they are insufficient to simulate the dynamic applications.

The paper describes a new method to investigate elastomer-lubricant compatibility and gives first results with a variety of lubricants.

HIGH performance and speciality elastomer applications are increasing in number as small, efficient engines are designed for the newer small cars. Engine rear crankshaft seals are one of the most demanding uses for fluoroelastomers today. They were first introduced in Europe during the 1960s for small, high rev/min engines. These seals have been refined and are today considered as standard in Europe. Fluoroelastomer rear crankshaft seals are being used on newly designed engines in the US and are presently being considered for older US rear crankshaft applications displacing rope packing, nitrile, polyacrylate and silicone. Engineers are finding that transverse engines and the confined or even “encapsulated” engine compartments have increased under‐the‐bonnet temperatures. Therefore, front crankshaft and, in some cases, camshaft (ohc) seals are being upgraded to the more thermal‐oxidatively stable fluoroelastomers.

AEROSPACE innovation, research and development, has about it an imperative factor. First is the constant striving for optimum safety, performance, comfort and the need, where appropriate, to compete effectively in the military segment. Further, when we refer to innovation within the aerospace concept, we mean true innovation rather than something tacked on to a component as an appendage, to satisfy fad or fashion. Sharper turns, longer range, higher ceilings and enhanced fire‐power result from authentic innovations; on a less dramatic plane, so does the prolongation of the life of the component — an imperative factor in relation to cost effectiveness. In an earlier article we outlined the contribution made by coatings to the protection of aerospace components and now we intend to similarly cover sister elements under the general head‐ing of ‘elastomers.’

Introduction in 1932 of neoprene, the first commercial synthetic elastomer, made it possible to attack many corrosion problems which had plagued engineers for years. Today, neoprene, and its newer companion Hypalon, synthetic rubbers are being put to use in virtually every industry to help solve an array of these persistent and costly problems. Some of the practical ways in which these two elastomers are helping in U.S. shipping and industrial concerns are dealt with in this article.