Search Results for standardization

This article presents the history of standardization in additive manufacturing (AM). It explains the need and structure for standardization in AM, including the application of AM standards by the industry sector. It also presents the primary purposes of these standards to create AM qualification and certification frameworks.

This article describes the types of repair and presents reasons for avoiding damage to a structure or component during repair. It discusses the major standardization issues with emphasis on design, repair materials, repair techniques, and inspection.

The organizations that are most active in the development of standards for powder metallurgy (PM) are the American Society for Testing and Materials (ASTM), Metal Powder Industries Federation (MPIF), and International Standards Organization (ISO). This article presents the test method standards, materials standards, and material designation codes for PM materials. It provides information on the codes for structural parts, PM soft magnetic materials, PM self-lubricating bearings, metal injection molded materials, and powder forged materials.

This article provides a perspective on United States (U.S.) Department of Defense (DOD) specifications, standards, handbooks, and related documents, as well as their role in the corrosion prevention and control activities in the U.S. military.

This article discusses the need, purposes, and objectives of codes and standards. It describes several types of codes, such as safety and trade codes, and the different types of standards, namely, industry consensus standards, product definition standards, and commercial standards. The article provides information on organizations that prepare codes and standards. It tabulates sponsoring organizations for the standards published by the American National Standards Institute and concludes with a discussion on a designer's responsibilities.

This article is a brief guide to information sources on nondestructive testing (NDT). It provides examples of some of the standards bodies commonly used by NDT personnel. These include the American Society for Testing and Materials (ASTM) International, European Committee for Standardization (CEN), American Society of Mechanical Engineers (ASME), International Organization for Standardization (ISO), Aerospace Industries Association (AIA), American Welding Society (AWS), American Petroleum Institute (API), and American Society for Nondestructive Testing (ASNT). All of these organizations used industry subject-matter experts and a consensus process in the development of their codes and standards.

This article contains a table that lists the ISO standards for the biological evaluation of medical devices.

This article defines quality, quality assurance, quality control, and quality management of processes, products, and services. It describes the evolution of quality control and quality assurance in the coatings industry. The article also discusses the standards, quality programs, and certifications in the coatings industry.

This article provides an overview of electromagnetic fields (EMFs) and discusses their direct and indirect effects on human health. It provides a detailed description of the exposure levels of EMFs in residential and work environments. The article examines the international and European standards and regulations regarding occupational exposure to EMFs encountered in industrial activities. It discusses the categories of work equipment or activities that may expose the worker above and under the orientation value. The article also describes the main principles underlying the protection system adopted for the frequency range of 50 Hz to 10 MHz.

Nuclear magnetic resonance (NMR) is a form of radio frequency spectroscopy based on interactions between nuclear magnetic dipole or electric quadrupole moments and an applied magnetic field or electric-field gradient. This article provides an overview of the fundamental principles of nuclear magnetic resonance with emphasis on nuclei properties, the basic equation of nuclear magnetic resonance, the classical theory of nuclear magnetization, line broadening, and measurement sensitivity. It describes the pulse-echo method for observing NMR. The article provides useful information on ferromagnetic nuclear resonance and nuclear quadrupole resonance, and illustrates the experimental arrangement of NMR with a block diagram. It also presents several application examples.

Electron probe microanalysis (EPMA) makes it possible to combine structural and compositional analysis in one operation. This article describes the basic concepts of microanalysis and the processing of EPMA that involves the measurement of the characteristic X-rays emitted from a microscopic part of a solid specimen bombarded by a beam of accelerated electrons. It provides information on the various aspects of energy-dispersive spectrometry (EDS) and wavelength-dispersive spectrometry (WDS), and elucidates the qualitative analysis of the major constituents of EDS and WDS. The article includes information on the analog and digital compositional mapping of elemental distribution, and describes the strengths and weaknesses of WDS and EDS spectrometers in X-ray mapping. It also outlines the application of EPMA for solving various problems in materials science.

This article primarily considers the problem of sampling bulk materials, including minerals, metals, environmentally important substances, and industrial raw materials and waste products. It provides useful information on sample types, sampling plan, optimizing sampling resources, practical aspects of sampling, and how to ensure the quality of sampling.

The Mossbauer effect (ME) is a spectroscopic method for observing nuclear gamma-ray fluorescence based on recoil-free transitions in a nucleus embedded in a solid lattice. This article provides an overview of the fundamental principles of ME and related concepts such as recoil-free fraction, absorption cross section, gamma-ray polarization, isomer shift, and quadrupole and magnetic interactions. It illustrates the experimental arrangement for obtaining ME spectra and presents several application examples.

This article discusses the application of thermodynamic in the form of phase diagrams for visually representing the state of a material and for understanding the solidification of alloys. It presents the derivation of the relationship between the Gibbs energy functions and phase diagrams, which forms the basis for the calculation of phase diagrams (CALPHAD) method. The article also discusses the calculation of phase diagrams and solidification by using the Scheil-Gulliver equation.

Rapid solidification is a tool for modifying the microstructure of alloys that are obtained by ordinary casting. This article describes the fundamentals of the four microstructural changes, namely, microsegregation, identity of the primary phase, identity of the secondary phase, and the formation of noncrystalline phases. It considers three factors to understand the fundamentals of these changes: heat flow, thermodynamic constraints/conditions at the liquid-solid interfaces, and diffusional kinetics/microsegregation. These factors are described in detail.