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.

Qualification of welding procedures and personnel is an important step to assure the quality and performance of any welded component or structure. This article summarizes common welding procedures, personnel qualification variables, and test methods. Welding procedure qualification tests can be categorized as either standard or special. The article discusses the purpose of qualifying a welding procedure to demonstrate that the resulting welds will meet prescribed quality standards and the qualification of the personnel.

This article provides an overview of the interfacial interactions with a lubricant film between a die and a metal, lubricant mechanisms, chemistry, qualification testing, application methods, and property test methods. It focuses on sheet metal-forming operations, although the discussions are relevant to metal-forming operations in general. The article also deals with lubricant selection as influenced by the metal to be formed and particular sheet-metal forming operations. The article also discusses some aspects of microbiology and toxicity in lubricants.

A wide range of flow-formed open- and close-ended shapes are currently available in a variety of difficult-to-form materials, including titanium alloys and nickel-base super alloys. This article describes the two basic methods of flow forming that are characterized by the position of the rolls during the forming process. The flow forming methods include staggered-roll flow forming process and in-line flow-forming process. Typical mechanical properties of flow-formed materials in various conditions are summarized in a table. Proper process controls and subsequent product qualification tests are critical to assure optimal performance of the flow-formed tubular component. The article discusses the most commonly required process control parameters and the effects of forming speed and temperature in the flow forming process.

Welding codes and standards usually require the qualification of welding procedures prior to being used in production. This is to ensure that welds will meet the minimum quality and mechanical property requirements for the application. This article provides an overview of the welding procedure qualification guidelines and test methods. It also reviews the codes, standards, and specifications that govern the design and fabrication of welded structures for the procedure qualification details that are appropriate for a given application.

This article discusses the standard test methods that can be applied to many types of welds: tension, bending, impact, and toughness testing. It provides information on four qualification stages, namely, the weld material qualification, base material qualification, the weld procedure qualification, and the weld service assessment. The article describes two general types of measurements for residual stress in welds: locally destructive techniques and nondestructive techniques. Locally destructive techniques include hole drilling, chip machining, and block sectioning. Nondestructive techniques include X-ray diffraction, neutron diffraction, Barkhausen noise analysis, and ultrasonic propagation analysis. The article concludes with an overview of weldability testing.

This article discusses the development of a welding procedure for friction stir welding (FSW), including the process of defining a preliminary procedure, the optimization of parameters, the development of supporting data, and other key features to ensure a successful procedure. The critical features of FSW tool design, initial process parameters, systematic welding trials, and robustness testing are reviewed. The article provides information on the common features of welding procedure qualification. It also includes a table that lists the procedures used in the production of sound friction stir welds in various aluminum alloys.

This article provides a discussion on general nondestructive evaluation (NDE) science and considerations for specific technique selection. It explains the basic concept of flaw detection and evaluation and probability of detection. The article provides an overview of NDE methods with their applications, limitations, and advantages. It includes details on NDE codes, calibration standards, inspection frequency, guidance on how to perform inspections, applicability, and mandatory and nonmandatory practice. The article also provides tips on where to focus inspections in order to align with the likely areas of damage or degradation and a number of other aspects of inspection.

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.

Stud arc welding (SW), also known as arc stud welding, is a commonly used method for joining a metal stud, or fastener, to a metal workpiece. This article serves as a basic information source for those interested in accomplishing one-sided, no-hole attachment of metal fasteners. It schematically illustrates the basic equipment used for stud arc welding and describes the operation of the welding process. The article discusses several specific applications that lend themselves to special variations of the stud arc welding technique. It concludes with information on quality control, qualification, and inspection of stud-welding.

Detailed analyses and test correlations are typically required to support design development, structural sizing, and certification. This article addresses issues concerning building block levels ranging from design-allowables coupons up through subcomponents, as these levels exhibit a wide variety of test-analysis correlation objectives. At these levels, enhanced analysis capability can be used most effectively in minimizing test complexity and cost while also reducing design weight and risk. The article discusses the examples of tests for which good correlative capability has shown significant benefit. These include notched (open and/or filled hole) tension and compression, inter/intralaminar shear and tension, and pin bearing.

Composites are complex engineered materials that often behave differently than common isotropic materials. Before testing a composite material, or before ordering or supervising such testing, the responsible party should review certain considerations. This article provides an overview of such considerations, namely, the differences between the testing of composites and testing of isotropic materials, role of certification agencies and importance of their involvement, building-block approach to composites testing, determining the purpose of testing, normalizing results, and statistical data reduction.

This article serves as a basic information source for those interested in accomplishing one-sided, no-hole attachment of metal fasteners. The stud arc-welding process is a substitute for fastening procedures such as drilling and tapping, bolting, and self-tapping screws. The article describes the operating principle of, and the tooling and equipment used for, the welding process. It contains tables that present information on the mechanical properties of aluminum, stainless steel, and low-carbon steel stud arc welded fasteners. The article details the different tests conducted to ensure the quality of stud arc-welded fasteners. It concludes with information on safety precautions to be followed in the welding process.