Search Results for lead plating

The orientation of the devices within a package determine the best chosen approach for access to a select component embedded in epoxy both in package or System in Package and multi-chip module (MCM). This article assists the analyst in making decisions on frontside access using flat lapping, chemical decapsulation, laser ablation, plasma reactive ion etching (RIE), CNC based milling and polishing, or a combination of these coupled with optical or electrical endpoint means. This article discusses the general characteristics, advantages, and disadvantages of each of these techniques. It also presents a case study illustrating the application of CNC milling to isolate MCM leakage failure.

This appendix lists plating solutions and procedures used in metallographic edge preparation.

This chapter discusses the key findings of an investigation into the failure of an aircraft engine fuel pump. It explains how investigators came to the conclusion that metal slivers from a heavily worn spring may have interrupted the flow of lubricant to one of the slipper pads, causing adhesive wear and the welding of slipper pad material onto the surface of a mating cam plate. Excessive friction between the slipper pads and cam plate, in turn, created a torsional overload that caused the camshaft to break. The chapter presents SEM images showing the wear pattern on one of the springs along with photographs of the damaged slipper pads and cam plate. It also includes an image of a copper flake found in one of the pistons and discusses the results of qualitative x-ray chemical analysis.

This article examines the role of alloying in the production and use of lead and tin. It describes the various categories and grades of lead and lead-base alloys along with their nominal compositions and corresponding UNS numbers. It also discusses the composition and properties of lead used in battery grids, type metals, and bearings. It, likewise, discusses the use of tin in various types of solder and in bearings and provides composition and property data for application-specific designations and grades. The article also discusses the effect of impurities in tin-lead solders and the amounts and combinations in which they are found.

This chapter covers a broad range of low-carbon steels optimized for structural applications. Low-carbon structural steels are generally considered the highest-strength steels that can be welded without undue difficulty, even in the field. They include mild steels, carbon-manganese and niobium- and vanadium-containing steels, and high-strength low-alloy steels. Chapter 5 discusses the composition, microstructure, and properties of these workhorse materials and explains how to identify the cause of production-related issues such as lamellar tearing and ferrite-pearlite banding. It also describes some of the alloying variations that have been developed to improve machinability and the mechanisms by which they work.

This chapter briefly reviews the history of brazing from ancient times to the early 20th century.

This chapter begins with a brief review of the different types of surface treatments and coatings used in industry and their effect on properties and performance. It then discusses the importance of corrosion and wear treatments and the consequences of failing to properly implement them in critical industries such as mining, energy production, transportation, and mineral and chemical processing. The chapter also describes basic approaches to dealing with corrosion and wear in steel.

This chapter discusses recycling processes used for metals, plastics, rubber, glass, and paper. Is also describes the advantages of recycled materials.

Stop-off coatings prevent nitriding of selected areas on components. This chapter discusses the processes, advantages, and disadvantages of stop-off techniques for gas nitriding, salt bath nitriding, and ion nitriding.

During cyclic spin tests, the turbine disc in an aircraft engine broke apart with a loud noise, followed by a fire. Based on a detailed examination and the results of SEM fractography and hardness measurements, failure analysts concluded that a locking plate became dislodged due to the shearing of the screws that hold it in place. They also provided recommendations to remediate the problem.

This chapter examines boiler tube failures attributed to operation-related causes. It discusses failures due to rapid start-ups, excessive load swing, excessive heat inputs, poor water chemistry control, and water-treatment methods.

This chapter discusses corrosion prevention methods used with aluminum and its alloys. The methods range from relatively straightforward measures, such as proper handling and storage, to advanced early warning corrosion monitoring systems for military aircraft. The chapter summarizes the basic factors that influence design for corrosion resistance and discusses the use of conversion coatings, organic coatings, porcelain enameling, and electroplating. It also discusses corrosion monitoring methods used in chemical processing and refining industries.

One of the rotor bearings in an electric motor failed, producing excessive vibrate. The bearing was removed and disassembled, revealing craters and bruises on the inner ring raceway and balls along with evidence of melting and burning of metal. Scanning electron microscopy revealed metal particles near the craters, and energy-dispersive x-ray analysis showed that slivers recovered from the grease had the same composition as the bearing raceway and balls. Based on these observations, it was concluded that the bearing failed due to electrostatic discharge, which would have led to seizure if it continued. The report recommends the use of electrically conductive grease and proper grounding practices.

This chapter outlines the major types of corrosion, their interactions, their complicating effects on fracture and wear, and some possible prevention methods. The types of corrosion considered in the chapter are galvanic corrosion, uniform corrosion, pitting corrosion, crevice corrosion, microbiologically influenced corrosion, stress-corrosion cracking, and corrosion fatigue.