There are many reasons why plastic materials should not be considered for an application. It is the responsibility of the design/materials engineer to recognize when the expected demands are outside of what the plastic can provide during the expected life-time of the product. This article reviews the numerous considerations that are equally important to help ensure that part failure does not occur. It provides a quick review of thermoplastic and thermoset plastics. The article focuses primarily on thermoset materials that at room temperature are below their glass transition temperature. It describes the motivation for material selection and the goal of the material selection process. The use of material datasheets for material selection as well as the processes involved in plastic material selection and post material selection is also covered.

The selection of engineered materials is an integrated process that requires an understanding of the interaction between materials properties, manufacturing characteristics, design considerations, and the total life cycle of the product. This article classifies various engineered materials, including ferrous alloys, nonferrous alloys, ceramics, cermets and cemented carbides, engineering plastics, polymer-matrix composites, metal-matrix composites, ceramic-matrix and carbon-carbon composites, and reviews their general property characteristics and applications. It describes the synergy between the elements of the materials selection process and presents a general comparison of material properties. Finally, the article provides a short note on computer aided materials selection systems, which help in proper archiving of materials selection decisions for future reference.

This article discusses the key factors that influence the selection of engineered materials for a particular application. Materials properties such as ultimate tensile strength, yield strength, hardness, and ductility, which chiefly define the performance or functional characteristics, are covered. This is followed by manufacturing process considerations such as material factors, shape factors, process factors, and the characteristics of fabricability, namely formability, workability, castability, machinability, and weldability.

Materials selection is an important engineering function in both the design and failure analysis of components. This article briefly reviews the general aspects of materials selection as a concern in proactive failure prevention during design and as a possible root cause of failed parts. It discusses the overall concept of design and describes the role of the materials engineer in the design and materials selection process. The article highlights the significance of materials selection in both the prevention and analysis of failures.

This article outlines the processes by which materials are selected to prevent or control localized corrosion, galvanic corrosion, and intergranular corrosion. It reviews the operating conditions and the design of candidate materials for material selection. The article discusses various corrosion-resistant materials, including ferrous and nonferrous metals and alloys, thermoplastics, reinforced thermosetting plastics, nonmetallic linings, glass, carbon and graphite, and catalyzed resin coatings. It examines an unusual form of intergranular corrosion known as exfoliation, which occurs in aluminum-copper alloys. The article also describes three types of erosion-corrosion: liquid erosion-corrosion, cavitation, and fretting. It concludes with information on the various factors to be considered for material selection, including minimum cost or economic design, minimum corrosion, minimum investment, and minimum maintenance.

Materials selection is closely related to the objectives of failure analysis and prevention. This article briefly reviews the general aspects of materials selection as a concern in both proactive failure prevention during design and as a possible root cause of failed parts. Coverage is more conceptual, with general discussions on the following topics: design and failure prevention, materials selection in design, materials selection for failure prevention, and materials selection and failure analysis. Because materials selection is just one part of the design process, the overall concept of design is discussed. The article also describes the role of the materials engineer in the design and materials selection process. It provides information on the significance of materials selection in both the prevention and analysis of failures.

In materials selection, a decision matrix method refers to any formalized procedure by which materials are ranked prior to a selection decision. This article describes the advantages and limitations of decision matrix methods, as well as the steps involved, with examples. The methods include the Pugh method, the Dominic method, and the Pahl and Beitz method. The article discusses the three important concepts in decision making: alternatives (candidate materials), criteria (objectives), and weighting factors.

This article provides a description of various systems for computer-aided materials selection that deals primarily with promising prototypes that have emerged for various applications. These include expert systems, quantitative selection systems, qualitative and experiential selection systems, and object-oriented systems.

This article describes the process of materials selection in relation to the design process, such as materials selection for a new design and materials substitution for an existing design. It reviews the performance characteristics of materials using prototype tests or field tests to determine their performance under actual service conditions. The article describes the selection of a material in relation to the manufacturing process and presents the factors that influence materials selection based on costs and related aspects. These factors include metallurgical requirements, dimensions, processing, quantity, packing, marking, and loading. The article discusses how the needs for materials data evolve as a design proceeds from conceptual to detail design. It describes the methods of materials selection, namely, cost per unit property method, weighted property index method, and limits on properties method.

This article describes the relationship between failure analysis and materials selection and a basic procedure for performing a failure analysis. It discusses the methods for analyzing failures to improve materials selection and presents examples that illustrate the use of failure analysis in materials selection and materials development/refinement.

This article provides an overview of cost analysis in materials selection. It discusses the several categories of alternatives for cost analysis. These include rules of thumb, accounting methods, and analytical methods. The article describes the methods for evaluating materials alternatives on the basis of both direct economic costs and indirect social costs. It considers the life cycle costs of alternative body-in-white designs and life cycle analysis. The various elements of cost are introduced with a case study concerned with the manufacture, use, and disposal of the automobile body-in-white.

The selection of the best material for a particular design is intimately associated with the decisions of how to process the material or manufacture a part. This article describes the basic characteristics of manufacturing processes such as material factors, shape factors, and process factors. The influence of materials on the manufacturing cost is described with a specific example. The article discusses the design for manufacturability to minimize the total number of parts, use readily processed materials, and eliminate machining and finishing operations. It reviews the factors influencing the selection of a material for production, including material composition, heat-treated condition, surface finish, and cost of material. The article describes the material characteristics, such as terms formability, workability, castability, machinability, and weldability, that aid or hinder the production of a part without defects.

Value analysis (VA) is a team problem-solving process to improve the value of a product from the viewpoint of a user. This article presents a comparison between VA and total quality management in materials selection and design. It discusses the key attributes, concepts, and activities of the VA. The application of value engineering in U.S. government contracts and the construction industry is reviewed. The article describes the eight phases of the VA process: preparation, information, analysis, creation, synthesis, development, presentation and report, and implementation and follow-up. It presents case studies that illustrate the materials-related aspects of the VA process.

This article is a compilation of definition of terms related to materials selection and its integration with engineering design processes.