No-bake sand molds are based on the curing of inorganic or organic binders with either gaseous catalysts or liquid catalysts. This article reviews the major aspects of no-bake sand bonding in terms of coremaking, molding methods, and sand processing. It discusses the points to be noted in handling sand-resin mixtures for no-bake molds or cones and lists some advantages of no-bake air-set cores and molds. The article describes the process procedures, advantages, and disadvantages of gas curing and air-setting hardening of sodium silicates. It examines the members of the air-setting organic binders, namely, furan no-bake resins, phenolic no-bake resins, and urethanes. The article provides an overview of gas-cured organic binders. It also illustrates the three commercial systems for sand reclamation: wet reclamation systems, dry reclamation systems, and thermal reclamation.

This article describes the characteristics of zinc-rich coatings that can be subcategorized according to the type of binder material used. It discusses the formulations of zinc-rich coatings with organic binders. The three major groups of inorganic zinc-rich coatings categorized by the Society for Protective Coatings are also discussed. These include postcured water-based alkali metal silicates, self-cured water-based alkali metal silicates, and self-cured solvent-based alkyl silicates. The article concludes with information on comparisons of inorganic with organic zinc-rich coatings.

The use of zinc in corrosion-protective coatings is due to its higher galvanic activity relative to that of steel. Pure zinc dust provides the best sacrificial protection to steel in a galvanic couple. Zinc-rich coatings can be subcategorized according to the type of binder material used, namely, inorganic and organic zinc-rich coatings. Common inorganic binders such as post-cured water-based alkali metal silicates, self-cured water-based alkali metal silicates, and self-cured solvent-based alkyl silicates, are reviewed. The article also compares inorganic and organic zinc-rich coatings, and discusses the concerns regarding zinc-rich coatings.

This article discusses two major sintering methods: pressureless and pressure-assisted sintering. Pressureless sintering techniques include vacuum and partial-pressure, hydrogen, and microwave sintering. Pressure-assisted consolidation techniques include overpressure sintering, sintering followed by postsinter hot isostatic pressing, hot pressing, and several rapid hot consolidation techniques. The article describes nitrogen sintering and the sintering of cermets. It reviews the furnaces used for sintering and presents the lubrication removal techniques. The article also outlines the need to control carbon and oxygen to obtain optimal properties and explains microstructure development and grain size control.

This article describes part selection, feedstock (powders and binders) characteristics and properties, tool design, and material and tooling for fabrication of metal powder injection molding (MIM) machines. It discusses the process parameters, operation sequence, molding machines, debinding techniques, consolidation (sintering) techniques, advantages, and limitations of MIM.

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.

Quality control of cemented carbides includes the evaluation of physical and chemical properties of constituent raw material powders, powder blends/formulations, green compacts, and fully dense finished product. This article provides a summary of the underlying principles and size ranges for the American Society for Testing and Materials (ASTM) standard methods of particle sizing and distribution. It presents the methods used to analyze the chemical composition of cemented carbide materials in a tabular form. The article also presents information on microstructural evaluation and physical and mechanical property evaluation of cemented carbides.

Consolidation and shaping of grade powders is carried out using several methods, depending on the size, complexity, shape, and quantity of parts required. This article details the powder consolidation methods of carbide powders: uniaxial pressing, cold isostatic pressing, extrusion, green machining, and injection molding.

Ceramic-forming processes usually start with a powder which is then compacted into a porous shape, achieving maximum particle packing density with a high degree of uniformity. This article compares and contrasts several forming processes, including mechanical consolidation, dry pressing, cold isostatic pressing, slip casting, tape casting, roll compaction, extrusion, and injection molding. It describes the advantages, equipment and tooling, and material requirements of green machining, the machining of ceramics in an unfired state with the intent of producing parts as close to as possible to their final shape. The article also provides useful information on drying methods, shrinkage, and defects as well as the removal of organic processing aids such as dispersants, binders, plasticizers, and lubricants.

Sand casting processes are typically classified according to the type of binder present in the molding sand mixture. This article discusses common sand casting processes and design considerations related to shape, gating, feeding, and pattern making methods. It describes the composition of sand and binder normally used, and provides information on the aluminum casting alloys produced. The article discusses precision sand casting and sand reclamation, and includes information on health and safety considerations.

This article discusses the methods and procedures used to extract, purify, and synthesize tungsten carbide powder, metal, and other refractory carbide/nitride powders used in hard metal production. Selection of powders, additives, equipment, and processes for making ready-to-press hard metal powders is also discussed. The article also provides information on the emerging technologies for tungsten carbide synthesis and binders in hard metal production, such as cobalt, iron, and nickel.

Casting can be done with either expendable molds for one-time use or permanent molds for reuse many times. This article lists the various methods used to fabricate expendable molds from permanent patterns. The methods include molding of sand with clay, inorganic binders, or organic resins; shell molding of sand with a thin resin-bonded shell; no-bond vacuum molding of sand; plaster-mold casting; ceramic-mold casting; rammed graphite molding; and magnetic (no-bond) molding of ferrous shot. The article tabulates a general comparison of casting methods and discusses the basic requirements of foundry molds.

Aggregate molding, or sand casting, is the gravity pouring of liquid metal into a mold that is made of a mixture molded against a permanent pattern. This article summarizes the most important materials in the process of sand casting of cast iron, including different types of molding aggregates, clays, water, and additives in green sand, chemically bonded organic resins, and inorganic binders in self-setting, thermosetting, and gas-triggered systems. It discusses three main types of reclamation systems: wet, dry, and thermal. The article concludes with a description of both nonpermanent and permanent mold processes.

According to International Organization for Standardization (ISO)/ASTM International 52900, additive manufacturing (AM) can be classified into material extrusion, material jetting, vat photo polymerization, binder jetting, sheet lamination, powder-bed fusion (PBF), and directed-energy deposition. This article discusses the processes involved in polymer powder 3D printing using laser fusion/ sintering and fusing agents and energy, as well as the thermally fused PBF. It provides information on polymer powder parameters and modeling, the powder-handling system, powder characterization, the flowability of powder feedstock, and polymer part characteristics. The article describes the types of polymers in PBF, the processes involved in powder recycling, and the prospects of PBF in AM. In addition, the biomedical application of polyether ether ketone (PEEK) is also covered.

This article reviews the basic types of mold aggregates and bonding methods for expendable molds and coremaking. It provides an overview of mold media and the basic types of sands and their properties. The most significant clays used in green sand operations, such as bentonites, are discussed. The article describes the methods of sand bonding with inorganic compounds. It provides a description of resin-bonded sand systems: no-bake binder systems, heat-cured binder systems, and cold box binder systems. The article concludes with a discussion on the media used for expendable molds, namely, ceramic shells and rammed graphite, for casting reactive metals such as titanium or zirconium.

This article discusses classification of foundry processes based on the molding medium, such as sand molds, ceramic molds, and metallic molds. Sand molds can be briefly classified into two types: bonded sand molds, and unbonded sand molds. Bonded sand molds include green sand molds, dry sand molds, resin-bonded sand molds, and sodium silicate bonded sand. The article describes the casting processes that use these molds, including the no-bake process, cold box process, hot box process, the CO2 process, lost foam casting process and vacuum molding process. The casting processes that use ceramic molds include investment casting, and plaster casting. Metallic molds are used in permanent mold casting, die casting, semisolid casting, and centrifugal casting.

This article discusses the process details of metal powder injection molding of microcomponents and the powder particle characteristics of feedstock and property requirements of binders. It reviews important characteristics to be considered in the processing steps: venting, channel diameters, binder segregation, binder degradation, feedstock supply, temperature control, demolding, debinding, and sintering. Finally, the article provides information on powder injection molding mold-filling simulation and two-component powder injection molding, offering a method for high-volume production of microcomponents made of multifunctional materials.