Search Results for injection-compression molding

Resin transfer molding and structural reaction injection molding belong to a family, sometimes denoted as liquid composite molding. This article provides information on the characteristics and automotive and aerospace applications of liquid composite molding. It reviews techniques that use hard tooling and positive (superatmospheric) pressures to produce structures. The techniques include vacuum-assisted resin injection, vacuum infusion, resin-film infusion, and injection-compression molding. The article provides an overview of the materials that are commonly used together with some of processing characteristics that are important to processing speed and part quality. It concludes with a discussion on design guidelines for the liquid composite molding.

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.

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.

This article describes key processing methods and related design, manufacturing, and application considerations for plastic parts. The methods include injection molding, extrusion, thermoforming, blow molding, rotational molding, compression molding/transfer molding, composites processing, and casting. The article describes principal features incorporated into the design of plastic parts. It concludes with a discussion on the materials selection methodology for plastics.

The compression molding process is most commonly called the sheet molding compound (SMC) process in reference to the precursor sheet molding compound material it uses. This article discusses the types of materials used for sheet manufacture, and describes the manufacturing and processing parameters of SMC components, providing details on tooling and process advantages and limitations. The article provides a general overview of the types of compression molding processes, including structural compression molding and thermoplastic compression molding.

Resin transfer molding (RTM) and structural reaction injection molding (SRIM) are two similar processes that are well suited to the manufacture of large, complex, and high-performance structures. This article discusses the similarities and differences of RTM and SRIM processes and the unique design considerations with respect to the physical properties, geometry, surface quality, process economics, equipment, and tooling of a component that should be considered in choosing RTM or SRIM over other competing processes for fabricating reinforced components.

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 discusses technologies focused on processing plastic materials or producing direct tools used in plastics processing. The article focuses on extrusion and injection molding, covering applications, materials and their properties, equipment, processing details, part design guidelines, and special processes. It also covers the functions of the extruder, webline handling, mixing and compounding operations, and process troubleshooting. Thermoforming and mold design are covered. Various other technologies for polymer processing covered in this article are blow molding, rotational molding, compression molding, transfer molding, hand lay-up process, casting, and additive manufacturing.

Vacuum infusion is a resin injection technique derived from resin transfer molding. This article discusses the characteristics of the technique and its applications. It presents the theory and background of the technique and provides an illustration of how parts are made. The article provides information on the equipment and material used for vacuum infusion. It describes the mechanical properties of components and summarizes the influence of production on the properties. The article concludes with a discussion on design guidelines.

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.

Blow molding has emerged as a commercially viable process for manufacturing parts for nonpackaging/industrial markets. This article discusses the machinery required, processing methods, mold types, process parameters, part designs and material distribution of blow molding. It provides an outline of the parison programming system equipped with blow molders to control the parison thickness. The article describes factors that are usually considered to minimize material distribution problems, namely, design, material selection, process control, part performance, and cost.

This article focuses on the axisymmetric 2.5-dimensional approach used in metal powder injection molding (PIM) simulations. It describes three stages of PIM simulations: filling, packing, and cooling. The article discusses the process features of numerical simulation of PIM, such as filling and packing analysis, cooling analysis, and coupled analysis between filling, packing, and cooling stages. It explains the experimental material properties and verification for filling, packing, and cooling stages in the PIM simulations. The article presents simulation results from some of the 2.5-dimensional examples to demonstrate the usefulness of the computer-aided engineering analysis and optimization capability of the PIM process.

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.

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.

This article describes the characteristics of thermoplastic composites and its material forms. It presents the steps and considerations in manufacturing the thermoplastic composites. The article describes the various techniques of manufacturing, such as consolidation, autoclave molding, diaphragm forming, compression molding, roll forming, bladder molding, liquid molding, filament winding, and pultrusion.