Material selection opportunities

The introduction of heat capacity into the relationships for thermal conductivity and the Prandtl number gives us an opportunity to make a clarification regarding these two quantities. Thermal conductivity is a true heat transport property it describes the ability of a material to transport heat via conduction. Heat capacity, on the other hand, is a thermodynamic quantity and describes the ability of a material to store heat as energy. The latter, while not technically a transport property, will nonetheless be described in this chapter for the various materials types, due in part to its theoretical relationship to thermal conductivity, as given by Eq. (4.35) and (4.36), and, more practically, because it is often used in combination with thermal conductivity as a design parameter in materials selection. 

This research was primarily funded by the Office of Naval Research, Grant No NOOO14-04-1-0703. The authors are also grateful to the National Science Foundation (MRSEC Award DMR 02138830). The authors would like to thank Perstorp Perstorp Specialty Chemicals AB for providing Boltom hyperbranched polyols. The authors thank Dr. Robert Stote for biodegradation measurements at Natick. In addition the authors thank the Polymer Performance, Degradation and Material Selection ACS Symposium Series organizers for the opportunity to present our work and for the preparation of this book. 

It is important to note that LCA is a tool to evaluate all environmental effects of a product or process throughout its entire life cycle. This includes identifying and quantifying energy and materials used and wastes released to the environment, assessing their environmental impact, and evaluating opportunities for improvement. LCA can also be used in various ways to evaluate alternatives including in-process analysis, material selection, product evaluation, product comparison, and policy-... 

This chapter intends to present the PSE tools, techniques, and areas of opportunities for embedding sustainability during material selection, process design, process and product modehng, and supply chain impfications. It also provides a perspective of the challenges to this task and the skill sets that will need to be developed to overcome those challenges successfully. 

Research Opportunity Algorithms to better predict costs of maintenance and protection against corrosion of infrastructure, which could enable effective up-front decisions about, for example, materials selection... 

Some particular requirements and typical selection considerations are presented in Table 8.2. The materials selection process is also influenced by the fact that the materials are either considered for the construction of a new system or for the modification or repairs in an existing facility. For the construction of new equipment, the selection procedure should begin as soon as possible and before the design is finalized. The optimum design for corrosion resistance will often vary with the material used. In a repair application, there is usually less opportunity for redesign, and the principal decision factors will be centered on delivery time and ease of fabrication in the field. It is also advisable to estimate the remaining life of the equipment so that the repair is not overdesigned in terms of the corrosion allowance. 

As a general rule, I try not to get involved in these kinds of questions. It is a sign that the questioner is not experienced with plastic material selection. As a consultant, and someone engaged in new business development, you might ask. How could you pass up a new client opportunity The truth of the matter is, working with clients like this is often more of a bother than it is worth. And sometimes the questions they ask make you shake your head. 

Even with a comprehensive plan for supply chain management there are still many opportunities to reduce material costs. As we stated earlier, material selection affects every single variable in the part cost equation. Since design and material selections are interrelated, design also affects every single variable in the part cost equation. 

Regardless of the actual response, the important thing to remember is that all sensory input results in a response, and that material selection can influence that response. We will discuss some of those influences later in this chapter. Thermoplastic materials offer unique opportunities to affect human response—not just because of their unique behavior, but also because of the capabilities to modify and enhance various properties through the use of additives. We can modify a thermoplastic material to do almost anything, and many of those modifications can also enhance a desired human response. 

Every effort has been made to select the most useful and most reliable information and to record it with accuracy. However, the editor s many years of involvement with handbooks bring a realization of the opportunities for gremlins to exert their inevitable mischief. It is hoped that users of this handbook will offer suggestions of material that might be included in, or even excluded from, future editions and call attention to errors. These communications should be directed to the editor at his home address (or by telephone). 

Environments deviating significantly from that of the laboratory, a selection of which is presented in Table 1, yet in which all the usual engineering functions must be performed, also pose problems and opportunities for material standards. Sensors (qv) must measure the attributes of these environments, constmction materials must withstand the exposure regimes, and performance criteria must be specified. 

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