Search Results for semisolid feedstocks

This chapter covers the practices and procedures used for shape casting metals and alloys. It begins with a review of the factors that influence solidification and contribute to the formation of casting defects. It then describes basic melting methods, including induction, cupola, crucible, and vacuum melting, and common casting techniques such as sand casting, plaster and shell casting, evaporative pattern casting, investment casting, permanent mold casting, cold and hot chamber die casting, squeeze casting, semisolid metal processing, and centrifugal casting.

This chapter describes the processes involved in alloy production, including melting, casting, solidification, and fabrication. It discusses the effects of alloying on solidification, the formation of solidification structures, supercooling, nucleation, and grain growth. It describes the design and operation of melting furnaces as well as melting practices and the role of fluxing. It also discusses casting methods, nonferrous casting alloys, and atomization processes used to make metal powders.

Generally, binders consist of at least three ingredients: a backbone to provide strength (compounds such as polyethylene, polypropylene, ethylene vinyl acetate, and polystyrene); a filler, such as polyacetal and paraffin wax, to occupy space between particles; and additives, such as stearates, stearic acid, or magnesium stearate, as well as phosphates and sulfonates, to adjust viscosity, lubricate tooling, disperse particles, or induce binder wetting of the powder. In the case of binders deposited via ink jet printing, the binder contains solvents to lower the viscosity for easier jetting. The chapter provides a detailed description of these constituents. The requirements of a binder as well as the factors determining the physical and thermal properties of polymers are discussed. Then, two factors associated with solvation of polymers, namely solubility parameter and wetting, are covered. The chapter ends with information on the specification of polymers used in binders.

This chapter reviews some of the differences between powder metallurgy and additive manufacturing and explains how they influence the microstructure and properties of various alloys and the formation of defects in manufactured parts.

This chapter gives a brief review of the development of additive manufacturing (AM) and the appeal of different of different AM methods.

This chapter discusses the advantages and disadvantages of metal matrix composites and the methods used to produce them. It begins with a review of the composition and properties of aluminum matrix composites. It then describes discontinuous composite processing methods, including stir and slurry casting, liquid metal infiltration, spray deposition, powder metallurgy, extrusion, hot rolling, and forging. The chapter also provides information on continuous-fiber aluminum and titanium composites as well as particle-reinforced titanium and fiber metal (glass aluminum) laminates.

This chapter provides basic engineering information on aluminum alloys with an emphasis on their use in applications where weight is a significant design factor. It discusses the advantages and limitations of various types of aluminum along with their compositions, designations, and achievable strengths. It explains how some alloys are hardened through solution strengthening and cold working, while others are strengthened by precipitation hardening. It also describes production and fabrication processes such as melting, casting, rolling, forging, forming, extruding, heat treating, and joining, and includes a section on the causes and effects of corrosion and how they are typically controlled.