Engineering plastics, as a general class of materials, are prone to the development of internal stresses which arise during processing or during servicing when parts are exposed to environments that impose deformation and/or temperature extremes. Thermal stresses are largely a consequence of high coefficients of thermal expansion and low thermal diffusivities. Although time-consuming techniques can be used to analyze thermal stresses, several useful qualitative tests are described in this article. The classification of internal stresses in plastic parts is covered. The article describes the effects of low thermal diffusivity and high thermal expansion properties, and the variation of mechanical properties with temperature. It discusses the combined effects of thermal stresses and orientation that result from processing conditions. The article also describes the effect of aging on properties of plastics. It explains the use of high-modulus graphite fibers in amorphous polymers.

Failure of structural polymeric materials under cyclic application of stress or strain is a subject of industrial importance. The understanding of fatigue mechanisms (damage) and the development of constitutive equations for damage evolution, leading to crack initiation and propagation as a function of loading or displacement history, represent a fundamental problem for scientists and engineers. This article describes the approaches to predict fatigue life and discusses the difference between thermal and mechanical fatigue failure of polymers.

Wrought 4xxx alloys (extrusions and forgings) exhibit high surface hardness, wear resistance, and a low coefficient of thermal expansion. This article provides a summary of brazing filler metals used to join brazeable aluminum-base metals. It contains tables that list the nominal composition and filler-metal alloys of 4xxx series used in structural forms.

The aluminum alloy 336.0 is a high-silicon alloy suitable for applications where good high-temperature strength, low coefficient of thermal expansion, and good resistance to wear are required. This datasheet provides information on key alloy metallurgy, processing effects on physical and mechanical properties, fabrication characteristics, and application characteristics of this 3xxx series alloy.

This article discusses the influence of microstructure and chemical composition on the physical properties of cast iron. The physical properties include density, thermal expansion, thermal conductivity, specific heat, electrical conductivity, magnetic properties, and acoustic properties. The article describes the properties of liquid iron in terms of surface energy, contact angles, and viscosity. The conductive properties such as thermal and electrical conductivity, of the main metallographic phases present in cast iron are presented in a table. The article discusses the magnetic properties of cast iron in terms of magnetic intensity, magnetic induction, magnetic permeability, remanent magnetism, coercive force, and hysteresis loss. It concludes with a discussion on the acoustic properties of cast iron.

This article describes the physical properties of powder metallurgy (PM) stainless steels. These include thermal diffusivity, conductivity, thermal expansion coefficient, Poisson's ratio, and elastic modulus. The article contains a table that lists the characteristics of various grades of PM stainless steels. It discusses the applications of various PM stainless steels such as rearview mirror brackets, anti-lock brake system sensor rings, and automotive exhaust flanges and sensor bosses.

This article is a comprehensive collection of tables that present information on the various thermal properties, namely, the coefficient of linear thermal expansion, thermal conductivity, and specific heat, of carbon and low-alloy steels.

In an induction heating system, thermal and electromagnetic properties of heated materials make the greatest impact on the heat transfer and performance of induction heating process. This article focuses on major thermal properties, namely, thermal conductivity, heat capacity, and specific heat. It describes the two important electromagnetic properties, electrical resistivity (electrical conductivity) and magnetic permeability, which posses the most pronounced effect on the performance of the induction heating system, its efficiency, and selection of main design parameters. The article also discusses the magnetic properties of diamagnetic, paramagnetic, ferromagnetic, ferrimagnetic, antiferromagnetic, and metamagnetic materials.

This article describes the two commonly used standardized tests for determining the mechanical properties of thermal spray coatings: hardness testing and tensile adhesion testing. It discusses the destructive and non-destructive methods of residual-stress measurement. Electrochemical testing methodologies include two distinctly different methods: direct and alternating current impedance techniques for assessing the corrosion resistance of coating attributes. The article also reviews the testing methods for determining thermomechanical and environmental stability of thermal barrier coatings. It discusses the wear testing methodologies that are standardized by ASTM, including the pin-on-disk, block-on-ring, dry sand/rubber wheel, erosion, metallographic apparatus abrasion, fretting wear, cavitation, reciprocating ball-on-flat, impact, and rolling contact fatigue test. The article concludes with a discussion on the methods of testing abradability and erosion resistance in abradable coatings.

This article presents a table that lists the linear thermal expansion of selected metals and alloys. These include aluminum, copper, iron, lead, magnesium, nickel, tin, titanium, and zinc and their alloys. Thermal expansion is presented for specific temperature ranges.

There are several main sources of thermophysical property data that provide the most authoritative and comprehensive compilations of critically and systematically evaluated data that are presently available. This article provides thermophysical property data to assist in the materials properties selection for the simulation of casting processes. The measurements of thermophysical property are difficult due to high temperatures and the reactivity of some alloys. The article discusses the strategies adopted to minimize the effects of high temperatures and reactivity of alloys. It presents the thermophysical properties of pure metals and some commercial alloys and tabulates the enthalpy of fusion and solidus and liquidus temperatures for various alloys of commercial interest. The article also lists the density, thermal conductivity, surface tension, and viscosity for some commercial alloys.

The material data for forging can be divided into two categories, namely, mechanical properties and thermophysical properties. This article describes the flow characteristics of key engineering materials, such as steels, aluminum alloys, copper alloys, titanium alloys, and nickel-base superalloys. It discusses the thermophysical properties for designing or optimizing a metalworking process: specific heat, coefficient of thermal expansion, thermal conductivity/diffusivity, and density.

Thermomechanical are used to gain insight into the causes of problems that arise during a given thermomechanical process. This article provides examples to demonstrate how significant the parameters were selected for specific tests. It examines the types of problems that can occur during a thermomechanical process. The article provides information on the thermophysical properties, which include specific heat, coefficient of thermal expansion, thermal conductivity/diffusivity, and density. It concludes with examples that illustrate how the various considerations in testing are successfully used to solve practical thermomechanical processing problems.

Elastomeric tooling uses rubber details to generate required molding pressure or to serve as a pressure intensifier during composite part curing cycles. This article discusses the various aspects of the forms of commercially available bag-side elastomeric caul systems. It describes the two basic methods, such as the trapped or fixed-volume rubber method and the variable-volume rubber method, of elastomeric tooling, which use the principles of thermal expansion molding. The significant properties and controlling equations that are required to characterize elastomeric tooling material are also discussed.

Characterization of nonmechanical properties is performed in the testing and certification of composite materials. This article focuses on the properties of composites that are commonly investigated. The properties include: per ply thickness; constituent content; density; coefficient of thermal expansion and coefficient of moisture expansion; glass transition temperature; thermal conductivity, diffusivity, and specific heat.

A unidirectional fiber composite (UDC) consists of aligned continuous fibers that are embedded in a matrix. This article describes a variety of analytical methods that are used to determine the various physical properties of the UDC. These properties include elasticity, thermal expansion coefficients, moisture swelling coefficients, static and dynamic viscoelastic properties, conductivity, and moisture diffusivity.

This article describes the factors to be considered while performing electroforming process. The factors include the shape and size of the mold, expected durability of the mold, required delivery time, and manufacture and cost of the necessary mandrel. The article discusses mandrel fabrication by either the use of fiberglass/resins or by the machining of the mandrel directly from computer-aided design data. It provides a comparison of nickel and other tooling materials in terms of coefficients of thermal expansion, thermal cycles for compression molding, and thermal cycles for metal autoclave molds.

The properties of unidirectional composite (UDC) materials are quite different from those of conventional, metallic materials. This article provides information on the treatment of UDC stress-strain relations in the forms appropriate for analysis of thin plies of material. It explains the development of the relations between mid-surface strains and curvatures and membrane stress and moment resultants. The article discusses the properties, such as thermal expansion, moisture expansion, and conductivity, of symmetric laminates and unsymmetric laminates. It describes the distribution of temperature and moisture through the thickness of a laminate. Stresses caused due to mechanical loads, temperature, and moisture on the laminate are analyzed. The article concludes with information on interlaminar cracking, free-edge delamination, and transverse cracks of laminates.

This article contains tables that present engineering data for the following metals and their alloys: aluminum, copper, iron, lead, magnesium, nickel, tin, titanium, zinc, precious metals, permanent magnet materials, pure metals, rare earth metals, and actinide metals. Data presented include density, linear thermal expansion, thermal conductivity, electrical conductivity, resistivity, and approximate melting temperature. The tables also present approximate equivalent hardness numbers for austenitic steels, nonaustenitic steels, austenitic stainless steel sheet, wrought aluminum products, wrought copper, and cartridge brass. The article lists conversion factors classified according to the quantity/property of interest.

Low-expansion alloys are materials with dimensions that do not change appreciably with temperature. Alloys included in this category are various binary iron-nickel alloys and several ternary alloys of iron combined with nickel-chromium, nickel-cobalt, or cobalt-chromium alloying. Low-expansion alloys are used in various applications such as rods and tapes for geodetic surveying, moving parts that require control of expansion (such as pistons for some internal-combustion engines), bimetal strip, components for electronic devices etc. This article discusses the properties, composition, and applications of iron-nickel low-expansion alloys (Invar), as well as other special alloys, including iron-nickel-chromium alloys, iron-nickel-cobalt alloys, iron-cobalt-chromium alloys, and high-strength, controlled-expansion alloys. It covers the factors affecting coefficient of thermal expansion of iron-nickel alloys, including heat treatment and cold drawing. Magnetic, physical, thermal, electrical and mechanical properties of iron-nickel alloys are also covered.