Surface treatments are applied to magnesium parts primarily to improve their appearance and corrosion resistance. Mechanical and chemical cleaning methods are used singly or in combination, depending on the specific application and product involved to ensure repetitive reliability. This article focuses on mechanical finishing methods, namely, barrel tumbling, polishing, buffing, vibratory finishing, fiber brushing, and shot blasting. It provides useful information on process control and difficulties with chemical and anodic treatments of magnesium alloys. The use and applications of plating and organic finishing of magnesium alloys are also reviewed. The article concludes with a description of health and safety precautions to be followed during the surface treatment process.

Mass finishing normally involves loading components to be finished into a container together with abrasive media, water, and compound. This article focuses on basic mass finishing processes, including barrel finishing, vibratory finishing, centrifugal disc and barrel finishing, spindle finishing, and drag finishing. It describes the various factors considered in selecting the most suitable mass finishing process. The article also provides information on consumable materials, process considerations, safety precautions, and waste disposal of mass finishing processes.

Mechanical plating is a method for coating ferrous metals, copper alloys, lead, stainless steel, and certain types of castings by tumbling the parts in a mixture of glass beads, metallic dust or powder, promoter or accelerator chemicals, and water. It offers a straightforward alternative method for achieving desired mechanical and galvanic properties with an extremely low risk of hydrogen embrittlement. This article provides a detailed description of the equipment, process steps, process capabilities, applicable parts, specific characteristics, advantages, limitations, post treatments, and waste treatment of mechanical plating.

Mechanical cleaning systems are used to remove contaminants of work surface by propelling abrasive materials through any of these three principal methods: airless centrifugal blast blade- or vane-type wheels; compressed air, direct-pressure dry blast nozzle systems; or compressed-air, indirect-suction (induction) wet or dry blast nozzle systems. This article focuses on the abrasive media, equipment, applications, and limitations of dry and wet blast cleaning. It discusses the health and safety precautions to be taken during mechanical cleaning.

Finishing refers to a wide variety of processes that generally involve material removal in one form or another to generate surfaces with specific geometries, tolerances, and functional or decorative characteristics. This article discusses four major finishing methods, namely, abrasive machining, electropolishing, mass finishing, and shot peening. In each case, it describes subtypes, process variations, and the associated equipment.

Zinc and zinc alloys require surface engineering prior to coating or use to improve adhesion and corrosion resistance. Die-cast zinc parts, in addition, must be trimmed and finished to remove flash and parting lines. This article covers zinc cleaning procedures as well as coating and finishing processes. It explains how to remove parting lines and presents several mechanical finishing methods, including surface polishing, brushing, controlled shot peening, and buffing. It also provides information on solvent cleaning, emulsion cleaning, aqueous detergent or alkaline cleaning), electrocleaning, acid dipping, and zinc conversion coating treatments.

This article describes the steps, bath composition and characteristics, equipment, plating rate, deposit thickness, and applications for different types of nonelectrolytic deposition processes, including electroless nickel plating, electroless copper plating and mechanical plating.

Mechanical finishes usually can be applied to aluminum using the same equipment used for other metals. This article describes the two types of grinding used in mechanical finishing: abrasive belt grinding and abrasive wheel grinding. It reviews the binders and fluid carriers used in buffing, and discusses satin finishing and barrel finishing. It also describes lapping and honing techniques that are of special interest in treating aluminum parts that have received hard anodic coatings. Honing recommendations for aluminum alloys are presented in a table.

The necessary precursor to a proper and durable finish is the preparation of the active aluminum surface to receive the desired protective finish that will allow it to have a long and attractive service life. This article helps those who work with aluminum in the many varieties of applications of such products. It describes the two main categories of cleaning that can be used with most any metal, namely, mechanical cleaning and chemical cleaning. The article provides a discussion on the laboratory evaluation of cleaners, field testing of cleaners, and cleaner types and procedures. It also describes the special cleaning procedures for aluminum alloys, such as steam cleaning and rotary wire-brush cleaning. The article reviews the use of temporary coatings and the use of maintenance coatings on aluminum. It provides information on the handling and storage procedures of aluminum alloys and the cleaning of specific applications of aluminum.

This article focuses on the mineral and organic acid cleaning of iron and steel. It begins with a discussion on the application methods, process selection criteria, solution composition, equipment used, and control of process variables in mineral acid cleaning. The article then describes the advantages and disadvantages of organic acid cleaning. Applications, including boiler cleaning, stainless steel cleaning, and removal of iron- and copper-bearing deposits, are discussed. The article concludes with an overview of acid cleaning of nonferrous alloys.

The selection of surface treatments for copper and copper alloys is generally based on application requirements for appearance and corrosion resistance. This article describes cleaning, finishing, and coating processes for copper and copper alloys. These processes include pickling and bright dipping, abrasive blast cleaning, chemical and electrochemical cleaning, mass finishing, polishing and buffing, electroless plating, immersion plating, electroplating, passivation, coloring, and organic coatings.

Commercial zinc plating is accomplished by a number of distinctively different systems: cyanide baths, alkaline noncyanide baths, and acid chloride baths. This article focuses on the composition, advantages, disadvantages, operating parameters, and applications of each of the baths. It provides information on the control of thicknesses of zinc specified for service in various indoor and outdoor atmospheres and on the similarities between cadmium and zinc plating.

Electrodeposits of cadmium are used to protect steel and cast iron against corrosion. This article provides an overview of the surface preparation of, and brighteners used in, cyanide baths. It focuses on the anode system, current density, deposition rates, and bath temperature of cadmium plating with attention to the materials of construction and equipment used. The article provides a description of the selection of plating method with examples, applications, and several postplating processes of cadmium plating.

Specialty steels encompass a broad range of ferrous alloys noted for their special processing characteristics (powder metallurgy alloys), corrosion resistance (stainless steels), wear resistance and toughness (tool steels), high strength (maraging steels), or magnetic properties (electrical steels). This article provides a detailed discussion on the various surface treatments, including cleaning, nitriding, carburizing, coating, and plating, performed on specialty steels.

Copper alloys are widely used as electroplated coatings. They can also be used with practically any substrate material that is suitable for electroplating. This article focuses on the solution composition and operating conditions for brass and bronze plating solutions. It describes the decorative and engineering applications of brass and bronze plating. The article also provides information on the treatment of waste water from brass and bronze plating operations.

This article describes the basic attributes of the most widely used metal surface cleaning processes to remove pigmented drawing compounds, unpigmented oil and grease, chips, cutting fluids, polishing and buffing compounds, rust and scale from steel parts, and residues and lapping compounds from magnetic particle and fluorescent penetrant inspection. The cleaning processes include emulsion cleaning, electrolytic alkaline cleaning, acid cleaning, solvent cleaning, vapor degreasing, alkaline cleaning, ultrasonic cleaning, and glass bead cleaning. The article provides guidelines for choosing an appropriate process for particular applications and discusses eight well-known methods for determining the degree of cleanliness of the work surface.

Metal surfaces must often be cleaned before subsequent operations to remove unwanted substances such as pigmented drawing compounds, unpigmented oil and grease, chips and cutting fluids, polishing and buffing compounds, rust and scale, and miscellaneous contaminants. The article describes common cleaning processes, including alkaline, electrolytic, solvent, emulsion, molten salt bath, ultrasonic and acid cleaning as well as pickling and abrasive blasting. It also explains how to select the appropriate process for a given soil type and surface composition.

This article describes the methods for removing metallic contaminants, tarnish, and scale resulting from hot-working or heat-treating operations on nickel-, cobalt-, and iron-base heat-resistant alloys. It provides a brief description of applicable finishing and coating processes, including polishing, electroplating, ceramic coatings, diffusion coatings, and shot-peening. The article presents numerous examples that identify cleaning and finishing problems and the procedures used to solve them.

Aluminum or aluminum alloy products have various types of finishes applied to their surfaces to enhance appearance or improve functional properties. This article discusses the procedures, considerations, and applications of various methods employed in the cleaning, finishing, and coating of aluminum. These include abrasive blast cleaning, barrel finishing, polishing, buffing, satin finishing, chemical cleaning, chemical brightening, electrolytic brightening, chemical etching, alkaline etching, acid etching, chemical conversion coating, electroplating, immersion plating, electroless plating, porcelain enameling, and shot peening.

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.