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Publisher Summary Plastics used in medical device applications must meet stringent performance requirements through production, packaging, shipping, end use, and disposal. Many devices and device kits are sterilized before they are shipped for use. During manufacturing and during end use they also come in contact with various chemicals, solvents, bodily fluids, skin, organs, and tissues. The materials used in such devices must be resistant to the sterilization methods, chemicals, and fluids that they encounter, be compatible with bodily fluids, skin, and tissues, and still maintain their safety, effectiveness, and functionality. Requirements for plastics used in medical devices include the following: 1. Material characterization, 2. Sterilization resistance, 3. Chemical and lipid resistance, 4. Extractables and leachables characterization, 5. Biocompatibility and hemocompatiblity, and 6. Shelf life and stability. Many devices need to be packaged and sterilized either before distribution or before use. Examples of such devices are exam and surgical gloves, clean room garments, specimen cups, wound care products, sutures, needles, syringes, catheters, drain bags, IV bags, fluid delivery systems, dialysis equipment, implants, surgical instruments, dental instruments, surgery supplies, and combination products. All materials used in such medical devices, including the plastics used in them, must be capable of being sterilized without loss of performance.

Bone defects are a major threat to human health, and heterotopic bone provides advantages that other materials do not provide in the treatment of bone defects. MPEG-PCL microspheres loaded with bone morphogenetic protein-2 (BMP-2/MPEG-PCL-MS) are an emerging means of culturing heterotopic bone. However, the effect of such microspheres on the quality of heterotopic bone osteogenesis has rarely been studied. The performance of heterotopic bone as a bone repair material has also rarely been reported. To explore the effect of microspheres on heterotopic bone osteogenesis and to explore the performance of heterotopic bone in bone repair, we designed compression tests, nanoindentation tests, and a finite element (FE) simulation. The effects of microspheres on the quality of heterotopic bone osteogenesis and performance of heterotopic bone as a bone repair material were evaluated from the mechanical properties, material properties, and FE simulation. The results demonstrate that eight-week heterotopic bone using microspheres has suitable mechanical and material properties, performs well in bone repair FE simulation, and can meet the material requirements of bone repair. Hence, this heterotopic bone as bone repair material has promising potential for clinical applications, and provides a good strategy for combination between tissue engineering and pharmaceutical science.

Maximum Material Condition (MMC) exists when a part or feature contains the maximum amount of material everywhere, e.g. minimum size hole, or maximum size shaft. In certain cases, its use allows an increase in the specified tolerance (often termed a bonus tolerance) if it is indicated that the tolerance applies to the feature at its maximum material condition. The maximum material requirement takes into account the mutual dependence of tolerances of size, form, orientation and/or location and permits additional geometrical tolerance as the part or feature departs from its maximum material condition. Least Material Condition (LMC) is that condition of a part or feature which contains the minimum amount of material, e.g. maximum size hole or a minimum size shaft. Circumstances do arise where, for example, a designer would want to limit the minimum wall thickness between a hole and the side of a component. This chapter identifies the geometrical tolerances for which MMC can be applied with illustrated examples and those that it cannot.

The supercritical water-cooled reactor (SCWR) is one of the six reactor concepts included under the umbrella of the Generation IV International Forum. Research on materials and chemistry for SCWRs dates back to the 1960s. A number of reactor concepts using water at supercritical temperature but subcritical pressures (nuclear steam) were studied. Significant experience was also obtained from the operation of supercritical fossil-fired power plants. In this chapter, the material requirements of the various SCWR concepts are introduced, with a focus on the European Union’s pressure vessel concept and the Canadian’s pressure tube concept. Furthermore, the key material degradation mechanisms relevant for SCWRs are summarized, state-of-the-art understanding of the key materials degradation issues is reviewed, and knowledge gaps are identified.

Some basic concepts in construction of biocomposites are discussed, such as the different types of biocomposites, the composing material classes, and the general families of production techniques. The conventional, solution-based, and additive manufacturing processing technologies for biocomposites are described and their applicability and base material requirements, i.e. whether they employ solutions or the undiluted composites/compounds are explored. The technologies discussed include extrusion/injection, filament winding, compression, autoclaving, infusion, solvent casting, phase separation, electrospinning, and solid freeform fabrication. Every section elaborates on the named production process itself and the resulting biocomposite construct, offering an indication of which technique is most appropriate for given product demands. The influence of the processing parameters on the composite material is evaluated, and some relevant design examples are presented. In conclusion, a comprehensive overview of the different techniques and their applicability is presented in tabular form.

This chapter discusses which material is the best for a specific piping or pipeline application, based on available data, economics, and prior experience. Materials are broadly grouped into ferrous, nonferrous, and plastic pipe. Each of the materials in each of these groups is discussed in detail. A thorough overview of ASME B31 Code requirements is discussed.

Following a review of requirements for materials employed for the manufacture of critical high temperature steam turbine components, metallurgical characteristics relating to three categories of creep resistant material are briefly reviewed, namely: low alloy ferritic steels, 9–12% Cr martensitic steels, and nickel base alloys. It is acknowledged that creep resistant steam turbine material requirements are largely determined by evolving energy and economic factors which are continuously varying in different parts of the world.

The chapter provides a range of standard principal for specified fire pumps. The chapter also describes the essential engineering and material requirements for all types of fire-fighting trucks, emergency vehicles and fire pumps utilized petroleum industries and gives general concepts for the manufacturing design of vehicles and relevant material, and equipment which have been installed on them. The application of the chapter would make uniformity in the design of equipment, their operation and maintenance, and also will facilitate the training of fire-fighting personnel. The pumps covered are intended to include material, fabrication, design, and engineering features concerned with installation and use in water supply systems and mobile equipment.

This chapter discusses materials selection and the main degradation mechanisms for each major component of the high temperature and low temperature cylinders used in steam turbines. The selection of appropriate materials and manufacturing processes allows efficiency improvements arising from enhanced design of steam turbines to be achieved with low risk of component failure.

Calcium phosphate cement (CPC)-based systems are self-setting bioactive biomaterials which demonstrate unique properties for spinal bone repair applications. The chapter describes a brief overview of the need for spinal repair and the associated minimally invasive surgical techniques that are currently used. Consequently, an overview of the main types of CPC-based systems is presented. The fundamental material requirements for spinal repair using minimally invasive surgical techniques are presented and technological efforts are being channelled to improve the properties of CPC-based systems. Finally, other clinical applications beyond spinal repair and future research initiatives are outlined.

This chapter provides a summary of the operating cycle of an industrial gas turbine and associated plant. The characteristics of the materials and integrated materials systems used in a gas turbine are considered. The conditions under which industrial gas turbines operate, and the impact these operating conditions have on materials behavior, are described. The materials selection criteria for individual components and component sections are discussed. The key material properties for designing critical components and the approach for conducting a life assessment are considered. The major limitations to the performance of current superalloys, coatings and steels and the challenges facing the introduction of new materials are discussed. An overview is given of current trends in materials development and future materials technologies.

Some basic concepts in construction of biocomposites are discussed, such as the different types of biocomposites, the composing material classes and the general families of production techniques. The conventional, solution-based and solid freeform fabrication processing technologies for biocomposites are described and their applicability and base material requirements, i.e. whether they employ solutions or the undiluted composites/compounds are explored. The technologies discussed include extrusion/injection, filament winding, compression, autoclaving, infusion, solvent casting, phase separation, electrospinning and solid freeform fabrication. Every section elaborates on the named production process itself and the resulting biocomposite construct, offering an indication of which technique is most appropriate for given product demands. The influence of the processing parameters on the composite material is evaluated, and some relevant design examples are presented. In conclusion, a comprehensive overview of the different techniques and their applicability is presented in tabular form.

Noise reduction is a big issue involved in the design and production of vehicle interior parts. This chapter focuses on the principles of noise control and engineering approaches for vehicle noise reduction using acoustic textile materials. Noise sources and noise paths in vehicles are first discussed. Mechanisms of textile materials for noise absorption and noise insulation in vehicle interiors are analyzed. Various noise control methods using different types of acoustic textile materials are illustrated by exhibiting some typical application cases. Finally, future trends in the new surface vehicle design and production are addressed, including new material requirements, novelty interior structures, and highly integrated acoustical interior systems.

This review addresses polymer electrolytes that have been demonstrated in direct methanol fuel cells. This work reviews the material requirements of polymer electrolytes and gives an exhaustive overview of the polymer electrolyte membranes (PEMs) investigated specifically for direct methanol fuel cells (DMFCs). This chapter then provides a framework for interpreting the reported performance and potential of PEMs in DMFC applications. Finally, this review presents and compares currently reported performance of DMFCs, particularly those using alternative membranes with some discussion of future research directions.

This chapter delves into the preparation involved just before the product is launched. It is a checklist for the new product development and discusses risk analysis for missing elements, accounting for deficits and the danger of an incomplete development program. Agency certifications are an integral part of the development process and explain the importance not launching unless the certifications are in place. The manufacturing pilot run is a verification of the several aspects of the newly developed product and determines the degree of variability allowable, the measures of performance, corrective action requirements, timing and staging, and process improvements. The report card on the entire effort is the beta testing program to make sure that all the elements of the planned process are in place. Literature is a term used to describe the management and dissemination of product (line) information. The process of managing the development of a new product involves repeated checking and the verification of many elements of the program. The chapter focusses on the training of personnel to ensure that the organization is ready to handle the new business. The next step is to set up the response centers, customer support team, and technical assistance. The best marketing program for the best product generally cannot succeed without the field sales organization providing the follow through in the customer's venue. The setting of final pricing is one of the crucial elements of a product launch. The material requirements from development prototypes through initial production are also discussed.

Publisher Summary Freeze-fracture deep-etch methods avoids the use of both chemical fixatives and cryoprotectants and results in the production of a three-dimensional replica of the etched surface of the specimen. Samples are ultra-rapidly frozen and fractured, the ice is sublimed under vacuum from the fracture surface, and the specimen is replicated. Using this technique, great advances have been made in the understanding of the structure and molecular make up of animal cell cytoplasm. The one main advantage of the rapid-freeze deep-etch technique is that little prior preparation of material is needed other than that required by the experiments that are being carried out. Therefore, most of the material requirements are in the instrumentation, and accessability to the necessary freezing and fracturing equipment is often the major limitation in the application of this technique. The procedure can be split into two separate events: freezing, followed by the fracturing, etching, and replication of the frozen material. Specimens can be frozen and stored under liquid nitrogen for any length of time prior to the fracturing procedure.

The general design of the Hermes Spaceplane thermal protection system (TPS) requires light-weight materials that will retain physical and mechanical properties under high temperatures in a re-entry environment. Based on the present configuration, mission specification (launch, orbital mission, re-entry) and overall structure design, material requirements have been identified. Classification of materials can be made according to their major function: • Materials with thermo-mechanical functions. These include advanced ceramic composite materials (like protected carbon-carbon and carbon-silicon carbide) and high temperature superalloys. • Materials with insulating functions. Of interest are advanced insulating material concepts (like the IMI internal multi-screen insulation) and material obtained by making up textiles (e.g. flexible blankets, textile seals). In order to gain confidence in the materials, extensive testing programs are underway, involving specific testing facilities. After a general overview of the type of material test required with respect to their function, some examples of high temperature equipment being implemented are briefly presented. Finally, specifications for new combined facilities, currently under study, are listed.

In recent years ion implantation has become a commonplace of semiconductor manufacture and it has also been applied with increasing success to a widening range of other material requirements. The review considers some of the factors - and, in particular, the successful prevention of space charge defocusing - which underlay this translation of the heavy ion accelerator from the scientific laboratory to the factory floor and it notes their possible impact on certain of the new and more demanding ion-beam implantation opportunities which are now emerging.

The properties, material requirements and manufacturing processes of wood–cement composites are shortly reviewed. The properties of wood as aggregate is discussed in detail. A review of pretreatment methods of woods which are otherwise unsuitable for manufacturing of wood–cement composites is given. A controlled aging and the addition of condensed silica fume enable the utilization of nearly all kinds of wood species. The properties of suitable cements and additives are dealed with. Wood–cement composites are durable and resistent against wood–destroying fungi and insects if the construction methods are adjusted to the properties of this material.

This paper is intended to provide some insight into planning for silver related activities by first examining some major supply, demand, and stock issues which are likely to influence the silver market in the 1980s. Following that are some specific ideas on planning for silver and other material requirements to reduce costs and increase profits.

The spectrum of modern permanent magnet materials is reviewed, with emphasis on those based on rare earth alloys. Characteristic compositions and the material requirements are identified. Properties of important magnet types and the role of different rare earths in achieving them are discussed. Technological uses for magnets are listed. Future prospects and limitations imposed by magnet properties and materials supply are considered.

Publisher Summary This chapter describes the measurements of reactor parameters in subcritical and critical assemblies. There are two types of experimental assemblies namely—exponential and zero-power critical. In practice, the use of these assemblies may be expensive and time consuming. A method that reduces the material requirements of the usual exponential or critical experiment is the substitution or two-region critical experiment used mainly for the measurement of the critical buckling. The values of the disadvantage factors and the thermal utilization obtained in subcritical assemblies seem to agree, and to give values appropriate to a critical assembly. The disadvantage factors, however, depend on averages of flux distributions and cross sections, and are less sensitive to differences in neutron energy distribution than the spatial distribution of the neutron density; the thermal utilization is still less sensitive. An attempt has been made to determine lattice parameters by means of measurements on a single fuel element.