Flammability is the ability of a material to undergo easy ignition and rapid flaming combustion. This article provides information on flammability tests of polymers and codes and regulations that cite these tests. Many organizations are involved in the characterization and specification of flammability properties, resulting in several categorization strategies for flammability tests, including tests for specific fire response characteristics, research tests versus acceptance tests, tests for different levels of severity, and tests for basis of origin. The article presents an overview on the basic approaches in improving the fire resistance of polymers and the burning process (heating, decomposition, ignition, combustion, and propagation). It provides a brief description on the test methods which are classified into two types, one based on fire response characteristics and the other on particular applications of polymeric materials.

Visual inspection (VI) is the oldest inspection technique man has used as a quality-control tool to evaluate products, assess their final form in terms of fabrication accuracy and external features based on experience, and decide on their acceptance or rejection. This article discusses the basic principles of visual inspection in terms of direct visual examination and indirect visual examination as well as advantages and limitations of visual inspection. It reviews the factors affecting the effectiveness of VI as a nondestructive testing (NDT): lighting conditions of observation, condition of surface under inspection, physical state/condition of inspector, proper training of personnel and level of expertise, and knowledge of applicable standards. The article provides schematic illustrations of rigid borescopes, fiberscopes, and videoscopes. It concludes with a discussion on automated optical inspection systems.

This article describes the coating materials, surface-preparation requirements, and application techniques used to protect underground pipelines. It provides a valuable insight into the types of polymer-based coatings that are both cost-effective and widely accepted in the pipeline industry.

The most widely accepted alloy and temper designation system for aluminum and its alloys is maintained by the Aluminum Association and recognized by the American National Standards Institute (ANSI) as the American National Standard Alloy and Temper Designation Systems for Aluminum (ANSI H35.1). This article provides a detailed discussion on the alloy and temper designation system for aluminum and its alloys. The Aluminum Association alloy designations are grouped as wrought and cast alloys. Lengthy tables provide information on alloying elements in wrought aluminum and aluminum alloys; nominal composition of aluminum alloy castings; typical mechanical properties of wrought and cast aluminum alloys in various temper conditions; and cross references to former and current cast aluminum alloy designations.

This article discusses the principles and limitations of micromagnetic techniques, namely, magnetic Barkhausen noise (MBN) and magnetoacoustic emission (MAE). It also discusses various factors limiting the establishment of acceptance criteria for test components as they pertain to the successful application of MBN measurement and signal interpretation. The article provides an overview of basic magnetic phenomena and dynamics in ferromagnetic materials that underlie the origin of MBN emissions. It describes the changes in the domain structure of the ferromagnetic material under an applied external field. The relationship between uniaxial stress and angular-dependent strain is also discussed. The influence of stress on domain walls, and therefore, the generation of Barkhausen noise are described. The article also describes the directional and angular MBN measurements and provides information on detection, angular dependence, and advanced analysis methods of MBN emissions.

The design process for ceramic materials is more complex than that of metals because of low-strain tolerance, low fracture toughness and brittleness. The application of structural ceramics to engineering systems hinges on the functional benefits to be derived and is manifested in the conceptual design for acceptable reliability. This article discusses the design considerations for the use of structural ceramics for engineering applications. It describes the conceptual design and deals with fast fracture reliability, lifetime reliability, joints, attachments, interfaces, and thermal shock in detailed design procedure. The article provides information on the proof testing of ceramics, and presents a short note on public domain software that helps determine the reliability of a loaded ceramic component. The article concludes with several design scenarios for gas turbine components, turbine wheels, ceramic valves, and sliding parts.

Chromium alloys yield alloy coatings with properties that range from completely satisfactory to marginally acceptable, depending on the end use. This article provides a detailed description of plating solutions and deposition conditions and rates of chromium-iron, chromium-nickel, and chromium-iron-nickel alloys.

X-ray spectroscopy is generally accepted as the most useful ancillary technique that can be added to any scanning electron microscope (SEM), even to the point of being considered a necessity by most operators. While “stand-alone” x-ray detection systems are used less frequently in failure analysis than the more exact instrumentation employed in SEMs, the technology is advancing and is worthy of note due to its capability for nondestructive analysis and application in the field. This article begins with information on the basis of the x-ray signal. This is followed by information on the operating principles and applications of detectors for x-ray spectroscopy, namely energy-dispersive spectrometers, wavelength-dispersive spectrometers, and handheld x-ray fluorescence systems. The processes involved in x-ray analysis in the SEM and handheld x-ray fluorescence analysis are then covered. The article ends with a discussion on the applications of x-ray spectroscopy in failure analysis.

Cutting fluids play a major role in increasing productivity and reducing costs by making possible the use of higher cutting speeds, higher feed rates, and greater depths of cut. After listing the functions of cutting fluids, this article then covers the major types, characteristics, advantages and limitations of cutting and grinding fluids, such as cutting oils, water-miscible fluids, gaseous fluids, pastes, and solid lubricants along with their subtypes. It discusses the factors considered during the selection of cutting fluid, focusing on machinability (or grindability) of the material, compatibility (metallurgical, chemical, and human), and acceptability (fluid properties, reliability, and stability). The article also describes various application methods of cutting fluids and precautions that should be observed by the operator.

This article outlines the fundamentals of polymer science and emphasizes the aspects that are necessary and useful to applications of engineering plastics. The basic structure of polymers influences the properties of both polymers and the plastics made from them. An understanding of this basic structure permits the engineers to understand which polymers may be acceptable for a certain application, and which may not. There are various possible classification schemes for polymers. Typical classification categories include polymerization process, chemical elements that make up the monomer, or crystalline versus noncrystalline structure. The article describes the various aspects of chemical structure that are important to an understanding of polymer properties and, thus, affect eventual end uses. It discusses different types of names assigned to polymers. The article details the aspects of polymer structure and examines the properties of polymers and the way they are altered by structure.

This article presents the three levels of investigations of distortion engineering. On Level 1, the parameters and variables influencing distortion in every manufacturing step must be identified. More than 200 parameters can affect distortion. The design of experiments approach allows for the investigation of larger numbers of parameters by a limited number of samples, and can be structured into system analysis, test strategy, test procedure, and test evaluation. Level 2 focuses on understanding the distortion mechanisms by using the concept of distortion potential and its carriers. Distortion engineering aims to compensate distortion using the so-called compensation potential (Level 3). Level 3 discusses the measures to improve homogeneity, and respectively the symmetry, of the carriers of the distortion potential. The article also discusses the compensation of the resulting size and shape changes of the existing asymmetries by well-directed insertions of additional inhomogeneity/asymmetries in one or more of the distributions of the carriers.

Independent verification of coating system performance can be based on laboratory testing and/or field exposure. Qualification testing is a critical component to coating system selection. This article focuses on performance evaluations that are used to prequalify coating systems, namely, facility-specific, industry-specific, coating-type-specific, or a combination of these. It describes the standard laboratory tests used to generate performance data, namely, physical, compositional, chemical exposure, and application characteristics tests. The pros and cons of using manufacturer-generated data versus independently generated data are discussed. The article provides information on accelerated corrosion/weathering testing and nuclear level 1/level 2 service coatings qualification. It also describes the procedures for establishing minimum performance requirements and for determining when requalification testing may be required.

Soluble salts on a surface can affect a steel substrate or coating in two principal ways: corrosion acceleration and osmotic blistering. This article provides a detailed discussion on the mechanisms for each of these deleterious effects. It describes the most detrimental anions with regard to corrosion, namely, chlorides, sulfates, and nitrates, and provides information on recognition and testing of the presence of soluble salts. The salt-measurement techniques and commercially available equipment are also described. The article provides information on research regarding tolerable levels of salts beneath coatings. The information shows that there appears to be a threshold limit to the salt contamination that a given coating/coating system can tolerate in a given environment.

This article briefly introduces the concepts of failure analysis, including root-cause analysis (RCA), and the role of failure analysis as a general engineering tool for enhancing product quality and failure prevention. It initially provides definitions of failure on several different levels, followed by a discussion on the role of failure analysis and the appreciation of quality assurance and user expectations. Systematic analysis of equipment failures reveals physical root causes that fall into one of four fundamental categories: design, manufacturing/installation, service, and material, which are discussed in the following sections along with examples. The tools available for failure analysis are then covered. Further, the article describes the categories of mode of failure: distortion or undesired deformation, fracture, corrosion, and wear. It provides information on the processes involved in RCA and the charting methods that may be useful in RCA and ends with a description of various factors associated with failure prevention.

This article describes the control of alloy composition and impurity levels in die casting of zinc alloys based on agitation, use of foundry scrap, and melt temperature and fluxing. It reviews the process considerations for the melt processing of the zinc alloys. The process considerations include the usage of furnaces and launder system, scrap return, inclusions in zinc alloys, fluxing of zinc alloys, and galvanizing fluxes. The article discusses the materials and lubricant selection, casting and die temperature control, and trimming process used in hot chamber die casting for zinc alloys. It also reviews other casting processes for zinc alloys, such as sand casting, permanent mold casting, plaster mold casting, squeeze casting, and semisolid casting.