Search Results for composition

A coating can be defined as a substance spread over a surface to provide protection or to serve decorative purposes. This article discusses two industrial coating components, namely, nonvolatile components such as the resin or binder, pigments, and any additives that may be incorporated into the formulation; and volatile components such as solvents, or water in emulsions and their composition. It provides general information on volatile organic compounds. The article describes the film-forming mechanisms of various coating types, namely, lacquers, chemically converting coatings, latex coatings, alkyds and other resins, which cure by oxidation, moisture-curing polyurethanes and inorganic zinc primers, and powder coatings. The article concludes with a discussion on the functions of the primer, intermediate coat, and topcoat in coating systems.

This article is a comprehensive collection of tables that list the nominal chemical composition of common powder metallurgy (PM) high-alloy tool steels, namely, PM high-speed, cold working, and corrosion-resistant tool steels.

This article contains a table that lists the values of nominal compositions and composition limits of wrought aluminum alloys.

This article contains a table that lists the values of nominal compositions and composition limits of aluminum alloy castings.

This article provides practical information and data on property development in engineering plastics. It discusses the effects of composition on submolecular and higher-order structure and the influence of plasticizers, additives, and blowing agents. It examines stress-strain curves corresponding to soft-and-weak, soft-and-tough, hard-and-brittle, and hard-and-tough plastics and temperature-modulus plots representative of polymers with different degrees of crystallinity, cross-linking, and polarity. It explains how viscosity varies with shear rate in polymer melts and how processes align with various regions of the viscosity curve. It discusses the concept of shear sensitivity, the nature of viscoelastic properties, and the electrical, chemical, and optical properties of different plastics. It also reviews plastic processing operations, including extrusion, injection molding, and thermoforming, and addresses related considerations such as melt viscosity and melt strength, crystallization, orientation, die swell, melt fracture, shrinkage, molded-in stress, and polymer degradation.

Chemical analysis is a critical part of any failure investigation. With the right planning and proper analytical equipment, a myriad of information can be obtained from a sample. This article presents a high-level introduction to techniques often used for chemical analysis during failure analysis. It describes the general considerations for bulk and microscale chemical analysis in failure analysis, the most effective techniques to use for organic or inorganic materials, and examples of using these techniques. The article discusses the processes involved in the chemical analysis of nonmetallics. Advances in chemical analysis methods for failure analysis are also covered.

Materials are selected and used as a result of a match between their properties and the needs dictated by the intended application. This article provides information on how the composition and structure determine the properties of materials. It describes common structural elements that are most important in materials. The article presents a historical perspective of the use of materials and illustrates the evolution of engineering materials.

This article describes the interaction of composition, manufacturing process, and composite properties of composites. The manufacturing process includes resin-matrix, metal-matrix, and carbon/carbon matrix processing. The article discusses various mechanical properties of composites. It explores how variations in the composition, manufacturing, shop process instructions, and loading/environmental conditions can affect the use of a composite product in a performance/service life operation.

The properties of irons and steels are linked to the chemical composition, processing path, and resulting microstructure of the material. Processing is a means to develop and control microstructure by hot rolling, quenching, and so forth. This article describes the role of these factors in both theoretical and practical terms, with particular focus on the role of microstructure in various irons. These include bainite, pearlite, ferfite, martensite, austenite, ferrite-pearlite, ferrite-cementite, ferrite-martensite, graphite, and cementite. The article discusses the evolution of microstructural change in rail steels, cast iron, and steel sheet. It contains tables that list the mechanical properties and compositions of selected steels. The article also discusses the basis of material selection of irons and steels.

This article focuses on the monolithic form of nonferrous alloys, including aluminum, copper, nickel, cobalt, titanium, zinc, magnesium, and beryllium alloys. Each metal and alloy offers unique combinations of useful physical, chemical, and structural properties that are made available by its particular composition and the proper choice of processing method. The article describes the composition, designation system, properties, and processing method of these metals and alloys. It discusses the effect of alloying elements in these alloys. The article explains microstructure/property relationships that are used to make specific properties available to the designers of structural applications. It provides examples of phase diagrams that illustrate eutectic and peritectic reactions.

This article provides a discussion on various types of glasses: traditional glasses, specialty glasses, and glass ceramics. It provides information on glazes and enamels and reviews the broad classes of ceramic materials. These include whitewares, structural clay products, technical ceramics, refractories, structural ceramics, engineering ceramics, and electronic and magnetic ceramics. General processing variables that can affect structure and compositional homogeneity are discussed. Traditional ceramics that include both oxide and nonoxide ceramics are also reviewed. The article concludes with several examples of engineering ceramics.

This article discusses the most fundamental building-block level, atomic level, molecular considerations, intermolecular structures, and supermolecular issues. It contains a table that shows the structures and lists the properties of selected commodity and engineering plastics. The article describes the effects of structure on thermal and mechanical properties. It reviews the chemical, optical, and electrical properties of engineering plastics and commodity plastics. An explanation of important physical properties, many of which are unique to polymers, is also included. The factors that must be considered when processing engineering thermoplastics are discussed. These include melt viscosity and melt strength; crystallization; orientation, die swell, shrinkage, and molded-in stress; polymer degradation; and polymer blends.