Materials selection is closely related to the objectives of failure analysis and prevention. This article briefly reviews the general aspects of materials selection as a concern in both proactive failure prevention during design and as a possible root cause of failed parts. Coverage is more conceptual, with general discussions on the following topics: design and failure prevention, materials selection in design, materials selection for failure prevention, and materials selection and failure analysis. Because materials selection is just one part of the design process, the overall concept of design is discussed. The article also describes the role of the materials engineer in the design and materials selection process. It provides information on the significance of materials selection in both the prevention and analysis of failures.

The intent of this article is to assist the failure analyst in understanding the underlying engineering design process embodied in a failed component or system. It begins with a description of the mode of failure. This is followed by a section providing information on the root cause of failure. Next, the article discusses the steps involved in the engineering design process and explains the importance of considering the engineering design process. Information on failure modes and effects analysis is also provided. The article ends with a discussion on the consequence of management actions on failures.

The purpose of this article is to assist the reader in understanding the role that an engineering expert witness plays in evaluating incidents related to product liability, so that he or she may become better acquainted with the role that an engineer plays in such litigation. The topics covered are admissibility of expert opinions, how to evaluate data, factual evidence, mandatory and voluntary standards, physical evidence, medical records, scientific literature, design decisions evaluation, environment of use, user's contribution, reports of opposing experts, report of findings, and deposition and trial testimonies.

This article introduces the design and manufacturing implications of additive manufacturing (AM) on part characteristics as well as on design opportunities and on manufacturing practices, supply chains, and even business models. In addition, it describes how they relate to the fundamental nature of AM processes and discusses the characteristics and purposes of AM processes and the parts they fabricate.

Understanding the mechanical properties of aluminum alloys is useful for the designer for choosing the best alloy and establishing appropriate allowable stress values, and for the aluminum producer to control the fabrication processes. This article discusses the nature and significance of mechanical property data and of stress-strain curves detailing the effects of mechanical properties on the design and selection of aluminum alloys. The properties include tensile, compressive, shear, bearing, creep and creep-rupture, fatigue, and fracture resistance properties.

This article aims to comprehensively review and summarize the material properties and engineering data for aluminum alloy castings and their many applications. The discussion focuses on conventional sand, permanent mold, and die castings as well as the premium engineered versions of some alloys. The article provides a summary of aluminum casting alloy designations of The Aluminum Association, the Unified Numbering System, and specific alloys considered premium strength by definition and by ASTM International and Aerospace Material Specifications. A distillation of data from published industry sources is given for a wide range of the properties and performance characteristics for topics such as: physical and thermophysical properties, typical and minimum mechanical properties, fatigue resistance, fracture resistance, and subcritical crack growth.

Understanding the mechanical properties of aluminum alloys is useful for the designer for choosing the best alloy and establishing appropriate allowable stress values, and for the aluminum producer to control the fabrication processes. This article discusses the nature and significance of mechanical property data and of stress-strain curves detailing the effects of mechanical properties on the design and selection of aluminum alloys. The properties include tensile, compressive, shear, bearing, creep and creep-rupture, fatigue, and fracture resistance properties.

This article provides a comprehensive matrix for selecting an aluminum filler alloy for the gas tungsten arc and gas metal arc welding processes, based on the various requirements or service conditions. A table lists the nominal strengths of aluminum filler metals.

Aluminum wrought products, castings, welds, and fasteners are used in many structural applications where they are required to safely support a load. It is useful to design aluminum structural components with its structural properties in mind from conceptualization rather than attempting to mimic components of other materials. This article discusses design specifications, design requirements and methods, and material properties used in aluminum structural design. These properties include tensile yield strength and tensile ultimate strength, welding, and ductility. The article describes various factors that affect the strength of two categories of aluminum structural components, namely members and connections. Design requirements for aluminum bolts, rivets, screws, and pins are provided. The article concludes with a discussion on the considerations for serviceability, namely deflections and vibrations.

Aluminum casting in steel and iron permanent molds is used widely throughout industry, and the vast majority of permanent mold castings are made of aluminum and its alloys. There are several methods used to cast aluminum in permanent molds. This article focuses on permanent mold casting with molten aluminum fed by gravity, low pressure, vacuum and centrifugal pressure, and squeeze casting. It discusses the major variables that affect the life of permanent molds, including pouring temperature, casting shape, cooling methods, heating cycles, storage, and cleaning. The article reviews the basic components of mold coatings: refractory fillers, binder, and carrier. Casting defects and suggested corrective actions for permanent mold casting are summarized in a table. The article concludes with a discussion on thin-wall permanent-mold castings.

The resistance welding processes commonly employed for joining aluminum are resistance spot welding, resistance seam welding, resistance roll welding, upset and flash welding for butt joining welding, and high-frequency resistance welding. This article discusses the general factors affecting resistance welding: electrical and thermal conductivities, rising temperature, plastic range, shrinkage, and surface oxide. It reviews the weldability of base materials such as Alclad alloys and aluminum metal-matrix composites. The article describes the joint design and welding procedures for resistance spot welding, as well as the joint type, equipment, and welding procedures for seam and roll spot welding. It concludes with information on flash welding, high-frequency welding, and cross-wire welding.

Weldability is a function of three major factors: base material quality, welding process, and design. This article focuses on base-metal weldability of aluminum alloys in terms of mechanical property degradation in both the weld region and heat-affected zone, weld porosity, and susceptibility to solidification cracking and liquation cracking. It provides an overview on welding processes, including gas metal arc welding, gas tungsten arc welding, resistance spot and seam welding, laser beam welding, and various solid-state welding processes. A review on joint design is also included, mainly in the general factors associated with service weldability (fitness). The article also provides a discussion on the selection and weldability of non-heat-treatable aluminum alloys, heat treatable aluminum alloys, aluminum-lithium alloys, and aluminum metal-matrix composites.

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.

The microstructure that develops during the solidification stage of cast iron largely influences the subsequent solid-state transformations and mechanical properties of the cast components. This article provides a brief introduction of methods that can be used for simulating the solidification microstructure of cast iron. Analytical as well as numerical models describing solidification phenomena at both macroscopic and microscopic scales are presented. The article introduces macroscopic transport equations and presents analytical microscopic models for solidification. These models include the dendrite growth models and the cooperative eutectic growth models. The article provides some solutions using numerical models to simulate the kinetics of microstructure formation in cast iron. It concludes with a discussion on cellular automaton (CA) technique that can handle complex topology changes and reproduce most of the solidification microstructure features observed experimentally.

This article discusses some of the factors that are linked directly to the casting design of ductile iron castings. It reviews the choice of molding process, application of draft, and patternmaker's allowance that should be taken into consideration in designing castings. The article describes the solidification shrinkage associated with the volume change that occurs during solidification, as well as strength and stiffness of ductile iron castings. It concludes with a discussion on the thermal deformation and residual stress in ductile iron castings.

Castability of alloys is a measure of their ability to be cast to a given shape with a given process without the formation of cracks/tears, pores/shrinkage, and/or other significant casting defects. This article discusses the factors which affect the fluidity of an iron melt: alloy composition and initial melt condition. Besides the basic alloy properties, the effective castability of high-alloy irons can be significantly improved through casting and casting system design. The article describes the product design and processing factors of high-alloy graphitic irons and high-alloy white irons. It explains the heat treatment of high-silicon irons for high-temperature service and concludes with a discussion on machining and finishing of high-alloy iron castings.

Thin-wall gray cast iron (TWGCI) can be seen as a potential material for the preparation of lightweight castings in automotive engineering applications. This article discusses the most important challenges for TWGCI: cooling rate, solidification, macrostructure, microstructure, and chilling tendency. It reviews the tensile properties and thermophysical properties of gray cast iron. The article describes the variables that influence molten iron preparation: charge materials, melting furnace thermal regime, chemical composition, modification and inoculation treatment, holding time/pouring procedure, mold properties (mold temperature, thermophysical properties of mold and mold coating), and casting design.

The morphology of the graphite particles in compacted graphite iron (CGI) is intermediate to the graphite particles found in gray iron or ductile iron. This article discusses the castability and product design of compacted graphite iron. The introduction of modern measurement and control technologies has made CGI a viable material for high-volume series production. The article describes the production of compacted graphite iron castings and the process control that depends on the production volume of components made from compacted graphite iron. It also discusses the process control for high-volume CGI commonly based on thermal analysis.