Malleable iron, like ductile iron, possesses considerable ductility and toughness because of its combination of nodular graphite and low-carbon metallic matrix. This article discusses melting practices such as batch cold melting and duplexing, and their control mechanisms. It schematically illustrates the microstructure of annealed ferritic malleable iron, which is characterized by microstructures consisting of uniformly dispersed fine particles of free carbon in a matrix of ferrite or tempered martensite. The article describes the digital solidification analysis technology, simulation technologies, and smart engineering for the production of malleable iron. It provides information on the applications of ferritic and pearlitic malleable irons.

This article demonstrates the depth and breadth of commercial and third-party software packages available to simulate metals processes. It provides a representation of the spectrum of applications from simulation of atomic-level effects to manufacturing optimization. The article tabulates the software name, function or process applications, vendor or developer, and website information.

Malleable iron is a cast ferrous metal that is initially produced as white cast iron and is then heat treated to convert the carbon-containing phase from iron carbide to a nodular form of graphite called temper carbon. This article provides a discussion on the melting practices, heat treatment, microstructure, production technologies, mechanical properties, and applications of ferritic, pearlitic, and martensitic malleable irons.

In order to model macrosegregation, one must consider convection and the partitioning of segregating elements at the dendritic length scale. This article describes microsegregation with diffusion in the solid. It presents a continuum model of macrosegregation and illustrates the simulation of macrosegregation and microsegregation.

This article reviews the emerging manufacturing technology that is alternatively called additive manufacturing (AM), direct digital manufacturing, free-form fabrication, three-dimensional (3-D) printing, and so on. It provides a broad contextual overview of metallic AM. The article focuses on the mechanical properties of AM-processed Ti-6Al-4V, IN-625, and IN-718. The development of closed-loop, real-time, sensing, and control systems is essential to the qualification and advancement of AM. This involves the development of coupled process-microstructural models, sensor technology, and control methods and algorithms. AM has the potential to revolutionize the global parts manufacturing and logistics landscape. It enables distributed manufacturing and the productions of parts on demand while offering the potential to reduce cost, energy consumption, and carbon footprint. The article explores the materials science, processes, and business considerations associated with achieving these performance gains. It concludes that a paradigm shift is required to fully exploit AM potential.

This article discusses the visual and microscopic characteristics of fractures of cast alloys. These fractures include ductile rupture, transgranular brittle fracture, intergranular fracture, fatigue, and environmentally induced fracture. The article also describes the factors that affect fracture appearance.

This article describes a method to predict mechanical properties of cast iron materials and illustrates how to use the predictions in computer-aided tools for the analysis of castings subjected to load. It outlines some ways to predict the hardness and elastic modulus of cast iron without going into dislocation theory. The article discusses modeling of hardness in cast iron based on a regular solution equation in which the properties of each phase depend on chemical composition and coarseness. It describes the evaluation of material parameters from the tensile stress-strain curve. The article concludes with an illustration of a finite-element method (FEM) model containing heterogeneous mechanical properties using local material definitions.

This article presents a detailed account of directed-energy deposition (DED) processes that are used for additive manufacturing (AM) of metallic materials. It begins with a process overview and a description of the components of DED systems followed by sections providing information on the process involved in DED and the materials used for DED. The postprocessing applied to the material after deposition is then covered. The article discusses the properties of metallic materials produced by using DED and ends with a discussion on applications for DED processes in various industries.

Additive manufacturing (AM) provides exceptional design flexibility, enabling the manufacture of parts with shapes and functions not viable with traditional manufacturing processes. The two paradigms aiming to leverage computational methods to design AM parts imbuing the design-for-additive-manufacturing (DFAM) principles are design optimization (DO) and simulation-driven design (SDD). In line with the adoption of AM processes by industry and extensive research efforts in the research community, this article focuses on powder-bed fusion for metal AM and material extrusion for polymer AM. It includes detailed sections on SDD and DO as well as three case studies on the adoption of SDD, DO, and artificial-intelligence-based DFAM in real-life engineering applications, highlighting the benefits of these methods for the wider adoption of AM in the manufacturing industry.

The raw materials used in thermal spray processes are a critical parameter in the finished coating because the variations in their size, morphology, chemistry, and phase composition can significantly impact coating properties. Therefore, it is important to test and characterize the raw materials. This article discusses various characterization methods for powders. Topics discussed include: methods for determining particle size and/or size distribution; powder and coating stoichiometry; particle chemistry; and phase analysis by x-ray diffraction. This article discusses the characterization of thermal spray powders which involves the determination of particle size and/or size distribution and phase analysis by x-ray diffraction. It provides information on preferential volatilization and rapid solidification that influence compositional differences. Wet chemical methods, spectographic analysis, and atomic absorption spectrometry are also discussed.

This article provides an overview of metal additive manufacturing (AM) processes and describes sources of failures in metal AM parts. It focuses on metal AM product failures and potential solutions related to design considerations, metallurgical characteristics, production considerations, and quality assurance. The emphasis is on the design and metallurgical aspects for the two main types of metal AM processes: powder-bed fusion (PBF) and directed-energy deposition (DED). The article also describes the processes involved in binder jet sintering, provides information on the design and fabrication sources of failure, addresses the key factors in production and quality control, and explains failure analysis of AM parts.

This article illustrates the simulation procedure of casting process. It describes important elements and points of the simulations. These include the setting of clear simulation objectives, selection of proper simulation code, hints in modeling of shape and phenomena, initial and boundary conditions, physical properties, enmeshing, and evaluation of simulation results. The article also provides some insights into the application of models to real world problem for foundry process engineers.

Computational fluid dynamics (CFD) is one of the tools available for understanding and predicting the performance of thermal-fluids systems. This article qualitatively describes the basic principles of CFD. The numerical methods, such as geometry description and discretization, used to solve the CFD equations are discussed. The article also demonstrates the application of CFD to a few casting problems.

Aluminum alloys, particularly the heat-treatable alloys, are sensitive to weld cracking. Anticipation of these characteristics and general knowledge of these materials assist in selection of suitable method for welding heat-treatable aluminum alloys. This article provides a general description of the metallurgy, characteristics, and applications of heat-treatable aluminum alloys and a detailed discussion on the characteristics of heat-treatable aluminum alloys, their resulting impact on the weld quality and property, along with the methods of avoiding or reducing the impacts. The impact created in the weld quality includes crack sensitivity, liquation cracking, porosity, and heat-affected zone degradation. The article provides an overview of filler alloy selection for reducing weld crack sensitivity and increasing weld strength, ductility, and corrosion resistance in the welds of heat-treatable aluminum alloys.

Titanium alloys are known for their high-temperature strength, good fracture resistance, low specific gravity, and excellent resistance to corrosion. Ti-6Al-4V is the most commonly used titanium alloy in the aerospace, aircraft, automotive, and biomedical industries. This article discusses various additive manufacturing (AM) technologies for processing titanium and its alloys. These include directed-energy deposition (DED), powder-bed fusion (PBF), and sheet lamination. The discussion covers the effect of AM on the microstructures of the materials deposited, static and mechanical properties, and fatigue strength and fracture toughness of Ti-6Al-4V.

High-pressure die casting is a fast method for the net shape manufacturing of parts from nonferrous alloys. This article reviews the automation technologies for the different stages or steps of the process. These steps include liquid metal pouring, injection, solidification, die open, part extraction, die lubrication, insert loading, and die close. Some manual aspects of the operations, together with automation options, are discussed. The article describes finishing steps, such as finish trimming, detailed deflashing, shot blast cleaning, and quality checks. Automation of the postcasting process is also discussed.

This article provides a general overview of additively manufactured steels and focuses on specific challenges and opportunities associated with additive manufacturing (AM) stainless steels. It briefly reviews the classification of the different types of steels, the most common AM processes used for steel, and available powder feedstock characteristics. The article emphasizes the characteristics of the as-built microstructure, including porosity, inclusions, and residual stresses. It also reviews the material properties of AM steel parts, including hardness, tensile strength, and fatigue strength, as well as environmental properties with respect to corrosion resistance, highlighting the importance of postbuild thermal processing.

This article describes the modification and inoculation of cast iron, and schematically illustrates the major effects of inoculation in gray cast irons. Inoculation could be considered as a common liquid-state treatment for all commercial cast irons (gray/compacted/ductile irons), while modification is essential to produce compacted graphite iron (intermediate level) and ductile iron. The article discusses the most important aspects of a gray cast iron inoculation treatment and the factors influencing its inoculation efficiency. It describes the modification and inoculation of ductile cast iron and compacted graphite cast iron.

This article discusses the requirements that are typically considered in designing a steel casting. It describes the materials selection that forms a part of process of meeting the design criteria. The article provides information on the material selection guide for five major design applications. It examines the attributes that are specific to the manufacturing of steel castings. The article concludes with information on the various nondestructive examination methods available for ensuring manufacturing quality and part performance in steel castings.

High-volume additive manufacturing (AM) for structural automotive applications, along the lines of economically viable technologies such as powder metallurgy, castings, and stampings, remains a lofty goal that must be realized to obtain the well-known advantages of AM. This article presents two key opportunities for AM related to automotive applications, specifically within the realm of metal laser powder-bed fusion: alloys and product designs capable of high throughput. The article also presents the general methodology of alloy development for automotive AM. It provides examples of unique designs for reciprocating components in elevated-temperature applications that are also exposed to demanding tribological conditions. The article also discusses the future of AM for automotive applications.