Bulk molding compounds can be molded into a variety of complex shapes by methods that can be readily automated for high volume production. This article describes the formulation and processing (compound formation, and molding methods) of bulk molding compounds. It discusses the effects of fiber type, fiber length, and matrix type on thermoset bulk molding compounds. The markets for long-fiber-reinforced bulk molding compounds are electrical, ordnance, aerospace, industrial, sporting goods, and automotive applications.

Molding compounds are plastic materials in varying stages of pellets or granulation that consist of resin, filler, pigments, reinforcement, plasticizers, and other ingredients ready for use in a molding operation. This article describes the material components and physical properties of sheet molding compounds (SMC). The three types of resin paste mixing techniques, such as batch, batch/continuous, and continuous, for an SMC operation are reviewed. The article discusses the design features and functional operations of the two types of SMC machines, namely, continuous-belt and beltless machines. It explains the formulation and processing of bulk molding compounds and reviews molding methods for bulk molding compounds, including compression, transfer, and injection molding. The effects of the fiber type and length and the matrix type on thermoset bulk molding compounds are discussed. It describes the four injection molding processes of injection molding compounds such as feeding, transporting, injecting, and flowing.

Manufacturing process selection is a critical step in plastic product design. The article provides an overview of the functional requirements that a part must fulfil before process selection is attempted. A brief discussion on the effects of individual thermoplastic and thermosetting processes on plastic parts and the material properties is presented. The article presents process effects on molecular orientation. It also illustrates the thinking that goes into the selection of processes for size, shape, and design factors. Finally, the article describes how various processes handle reinforcement.

This article is a compilation of abbreviations of terms, techniques, standards, compounds, and properties of materials that are relevant to the characterization and failure analysis of plastics.

The goal of design is to improve the overall performance of the metal or ceramic matrix rather than to create a material with different response than the base matrix. This article focuses on the design for manufacturing polymeric composites. Specially developed methods including contact molding, compression-type molding, resin-injection molding, and pultrusion are described. The article also discusses the various factors to be considered in designing for composite manufacturing.

Additives for plastics and elastomers are used to increase the ease of processing and to improve the properties of the final product. Additives improve processing characteristics by increasing lubricity and by stabilizing the polymer. Additives that improve properties include those that decrease static charge development and microbial activity and those that improve flame retardation characteristics, color, light stability, impact resistance, density and mechanical properties. This article focuses on the additives for polymers and elastomers that are used for improving processing--blowing agents, mold-release agents, lubricants, plasticizers, and heat stabilizers--and for improving properties antimicrobials, antioxidants, antistatic agents, colorants, fillers and fiber reinforcements, flame retardants, impact modifiers, light stabilizers, plasticizers, and heat stabilizers. Furthermore, it discusses the method for addition of these additives and the problems faced during compounding.

Designing composites for structural performance initially involves meeting a set of desired performance specifications at a minimum cost. This article discusses the factors that are considered in designing the manufacturing of polymeric composites. It describes the various aspects of manufacturing, forming process, and post-processing and fabrication for designing the composites.

Elastomeric tooling uses rubber details to generate required molding pressure or to serve as a pressure intensifier during composite part curing cycles. This article discusses the various aspects of the forms of commercially available bag-side elastomeric caul systems. It describes the two basic methods, such as the trapped or fixed-volume rubber method and the variable-volume rubber method, of elastomeric tooling, which use the principles of thermal expansion molding. The significant properties and controlling equations that are required to characterize elastomeric tooling material are also discussed.

This article is a comprehensive collection of engineering tables providing information on the mechanical properties of and the techniques for processing and characterizing polymeric materials, such as thermosets, thermoset-matrix unidirectional advanced composites, and unreinforced and carbon-and glass-reinforced engineering thermoplastics. Values are also provided for chemical resistance ratings for selected plastics and metals, and hardness of selected elastomers.

This article begins with a discussion on the driving forces for recycling composites. It reviews the recycling process of thermoset-matrix composites and thermoplastic-matrix composites. The recycling of thermoset-matrix composites includes regrind, chemical, energy recovery, and thermal processes. Thermoplastic-matrix composites are recycled by regrinding, compounding/blending and reprocessing. The article concludes with discussion on the properties of recycled composite fibers.

Injection molding is a process of forcing or injecting a fluid plastic material into a closed mold. The process generally has the advantages of being more readily automated and of permitting finer part details. Injection-molding compounds are thermoplastic or thermosetting materials and their composites that are specifically formulated for the injection-molding process. This article discusses the injection molding process, which includes the two basic categories of thermoplastic and thermoset injection molding, and lists the common thermoplastic and thermoset molding compounds and applications. It also describes the operation of the different types of injection molding machines as well as mold design and process controls. The article also describes the selection of injection-moldable thermosets, and provides an overview of part performance, properties, blowing agents, and aesthetic concerns related to thermoplastic structural-foam injection molding.

This article is a compilation of abbreviations, symbols, and tradenames for terms related to the properties, selection, processing, and applications of the most widely used nonmetallic engineering materials.

This article explains the key features of the manufacturing techniques for polymer composites. It describes the selection of a technically and economically feasible manufacturing technique for a composite design. The article discusses widely accepted and emerging techniques to manufacture polymer composites such as open-mold techniques.

This article presents a comprehensive collection of the definition of terms related to metallurgy.

A thermosetting resin, or thermoset, is a synthetic organic polymer that cures to a solid, infusible mass by forming a three-dimensional network of covalent chemical bonds. Significant applications include construction and thermoset engineering plastics. This article discusses the general and family characteristics of thermosetting resin families, including allyls, aminos (urea formaldehyde and melamine formaldehyde), cyanates, epoxies, polybenzimidazoles, unsaturated polyesters, thermoset polyimides, phenolics, and vinyl esters. It also explains processing methods, including curing and curing agents. The article provides descriptions of commercial product forms and the wide array of applications of thermosetting resins. It also tabulates the performance properties (mechanical, thermal, electrical and chemical resistance) of some families of unfilled or unreinforced thermosetting resins and reinforced or filled grades.

The design and analysis of aerospace and industrial composite components and assemblies requires a detailed knowledge of materials properties, which, in turn, depend on the manufacturing, machining, and assembly methods used. This article, through several tables and graphs, provides the mechanical properties, physical properties, and service characteristics of representative composite fiber-resin combinations, including thermoplastic matrix composites such as thermoplastic polyester resins, thermoplastic polyamide resins, and thermoplastic polysulfone resins, and thermoset matrix composites such as thermoset polyester resins, thermoset phenolic resins, thermoset epoxy resins, thermoset polyimide resins, and thermoset bismaleimide resins.

This article discusses the advantages of polymer matrix composite for automotive application in terms of design drivers, noise, vibration, harshness efficiency, process materials property constraints, safety and reliability, design optimization, structural and appearance requirements, recyclability, and processability. It describes the properties of high-volume composites used in automotive industries. The article provides a discussion on state-of-the-art and developing technologies in automotive field.

This article discusses the family characteristics, commercial forms, applications, resin grades, and mechanical and physical properties of traditional engineering thermoplastics in their neat (unmodified) form and as compounds and composites, namely, acrylonitrile-butadiene-styrenes, acrylics, high-density polyethylenes, reinforced polypropylenes, high-impact polystyrenes, polyvinyl chloride, styrene-acrylonitriles, and styrene-maleic anhydrides.