Search Results for pulse-echo method

Ultrasonic inspection is a nondestructive method in which beams of high frequency acoustic energy are introduced into a material to detect surface and subsurface flaws, to measure the thickness of the material, and to measure the distance to a flaw. This chapter begins with an overview of ultrasonic flaw detectors, ultrasonic transducers, and search units and couplants. It then discusses the principles of operation, presentation, and interpretation of data of pulse echo and transmission methods. This is followed by sections providing information on general characteristics of ultrasonic waves and the factors influencing ultrasonic inspection. The advantages, disadvantages, and applications of ultrasonic inspection are finally compared with other methods of nondestructive inspection of metal parts.

This chapter discusses the use of nondestructive inspection methods, including visual, ultrasonic, radiographic, and thermographic techniques, and the types of flaws and damages they can reveal in composite parts and assemblies. It describes the basic principles behind each method along with best practices and procedures.

The scanning acoustic microscope (SAM) is an important tool for development of improved molded and flip chip packages. The SAM used for integrated circuit inspection is a hybrid instrument with characteristics of both the Stanford SAM and the C-scan recorder. This chapter presents the historical development of SAM for integrated circuit package inspection, SAM theory, and analysis considerations. Case studies are presented to illustrate the practical applications of SAM. Other non-destructive imaging tools are briefly discussed, as well as SAM challenges and methods including spectral signature analysis and GHz-SAM.

Welded joints in any component or structure require a thorough inspection. The role of nondestructive evaluation (NDE) in the inspection of welds is very important, and the technology has become highly developed as a result. This article describes the applications, methods, evaluation procedures, performance, and limitations of NDE. It provides information on the training and certification of NDE operators, evaluation of test results, and guidance to method selection. Typical examples of various NDE methods for welds are also described.

Weldments made by the various welding processes may contain discontinuities that are characteristic of that process. This chapter discusses the different welding processes as well as the discontinuities typical of each process. It provides a detailed discussion on the methods of nondestructive inspection of weldments including visual inspection, liquid penetrant inspection, magnetic particle inspection, radiographic inspection, ultrasonic inspection, leak testing, and eddy current and electric current perturbation inspection. The chapter also describes the properties of brazing filler metals and the types of flaws exhibited by brazed joints.

This chapter discusses the critical soldering faults that lead to quality degradation and potential failure of a soldered connection. It then describes the types of nondestructive evaluations used to inspect soldered and brazed joints, including dimensional and visual inspection, ultrasonic testing, radiographic examination, dye penetrant inspection, and leak testing, including overpressure tests. The chapter also provides an overview of destructive physical analysis.

This chapter discusses the primary methods used to repair composites, including fill repairs, injection repairs, bolted repairs, and bonded repairs. It also discusses issues associated with field repairs.

This chapter focuses on the inspection of steel bars for the detection and evaluation of flaws. The principles involved also apply, for the most part, to the inspection of steel wire. The nondestructive inspection methods discussed include magnetic particle inspection, liquid penetrant inspection, ultrasonic inspection, and electromagnetic inspection. Eddy current and magnetic permeability are also covered.

The inspection of castings normally involves checking for shape and dimensions, coupled with aided and unaided visual inspection for external discontinuities and surface quality. This chapter discusses methods for determining surface quality, internal discontinuities, and dimensional inspection. Casting defects including porosity, oxide films, inclusions, hot tears, metal penetration, and surface defects are reviewed. Liquid penetrant inspection, magnetic particle inspection, eddy current inspection, radiographic inspection, ultrasonic inspection, and leak testing for castings are discussed. The chapter provides information on the procedures involved in the inspection of castings that are limited to visual and dimensional inspections, weight testing, and hardness testing. It also discusses the use of computer equipment in foundry inspection operations.

This chapter discusses the types of sensors used in sheet forming operations and the information they provide. It explains how force sensors protect equipment from overloads due to tool wear, friction, and misfeeds, how displacement and proximity sensors help to prevent die crashes, how acoustic emission, ultrasonic, and eddy current sensors detect tool breakage and part defects such as cracks, and how roller ball and optical sensors measure material flow. It also discusses the role of draw-in, wrinkle, oil-monitoring, and vision sensors and explains how material properties can be derived in real time from various sensor outputs.

This chapter provides an overview of the various inspection methods used with metals and alloys, namely visual inspection, coordinate measuring machines, machine vision, hardness testing, tensile testing, chemical analysis, metallography, and nondestructive testing. The nondestructive testing methods discussed are liquid penetrant inspection, magnetic particle inspection, eddy current inspection, radiographic inspection, and ultrasonic testing.

Discontinuities are interruptions in the desirable physical structure of a weld. This article describes the types of weld discontinuities that are characteristic of the principal welding processes. Discontinuities covered are metallurgical discontinuities, discontinuities associated with specialized welding processes, and base metal discontinuities. In addition, information on the common inspection methods used to detect these discontinuities is provided.

This chapter concentrates almost exclusively on inspection techniques related to pressure vessels and pipework. The discussion covers the general aspects associated with inspection and the key factors relevant to it. In addition, the chapter addresses processes involved in data collection and management, namely data acquisition, reporting, trending, reviewing, and auditing. Capabilities and limitations of in-service inspection techniques are discussed in the Appendix to this chapter.

Laser Voltage Probing (LVP) is a key enabling technology that has matured into a well-established and essential analytical optical technique that is crucial for observing and evaluating internal circuit activity. This article begins by providing an overview on LVP history and LVP theory, providing information on electro-optical effects and free-carrier effects. It then focuses on commercially available continuous wave LVP systems. Alternative optoelectronic imaging and probing technologies for fault isolation, namely frequency mapping and laser voltage tracing, are also discussed. The subsequent section provides information on the use of Visible Laser Probing. The article closes with some common LVP observations/considerations and limitations and future work concerning LVP.

This chapter covers the steps and tests that are important to produce quality parts in heat treating. The quality tests discussed include hardness tests, such as Brinell, Rockwell, and microhardness tests. The chapter also examines tensile testing, toughness testing, optical metallography, and nondestructive testing. The chapter concludes by discussing in-process inspections and the final inspection.

This chapter presents several materials and processes related to soldering technology. It first provides information on lead-free solders, followed by sections devoted to flip-chip processes, diffusion soldering, and modeling. Scanning acoustic microscopy and fine-focus x-ray techniques are also discussed. The chapter describes several evaluation procedures and tests developed to measure solderability and standards for process calibration. The chapter also describes the characteristics of reinforced solders, amalgams used as solders, and other strategies to boost the strength of solders. Further, the chapter considers methods for quantifying the mechanical integrity of joints and predicting their dimensional stability under specified environmental conditions. It discusses the effects of rare earth elements on the properties of solders. The chapter concludes with information on advanced joint characterization techniques.

This chapter discusses the advantages and disadvantages of metal matrix composites and the methods used to produce them. It begins with a review of the composition and properties of aluminum matrix composites. It then describes discontinuous composite processing methods, including stir and slurry casting, liquid metal infiltration, spray deposition, powder metallurgy, extrusion, hot rolling, and forging. The chapter also provides information on continuous-fiber aluminum and titanium composites as well as particle-reinforced titanium and fiber metal (glass aluminum) laminates.

Metal-matrix composites can operate at higher temperatures than their base metal counterparts and, unlike polymer-matrix composites, are nonflammable, do not outgas in a vacuum, and resist attack by solvents and fuels. They can also be tailored to provide greater strength and stiffness, among other properties, in preferred directions and locations. This chapter discusses the processes and procedures used in the production of fiber-reinforced aluminum and titanium metal-matrix composites. It explains how the length and orientation of reinforcing fibers affect the properties and processing characteristics of both aluminum and titanium composites. It also provides information on fiber-metal laminates and the use of different matrix metals and reinforcing materials.