Due to the recent requirement of higher integration density, solder joints are getting smaller in electronic product assemblies, which makes the joints more vulnerable to failure. Thus, the root-cause failure analysis for the solder joints becomes important to prevent failure at the assembly level. This article covers the properties of solder alloys and the corresponding intermetallic compounds. It includes the dominant failure modes introduced during the solder joint manufacturing process and in field-use applications. The corresponding failure mechanism and root-cause analysis are also presented. The article introduces several frequently used methods for solder joint failure detection, prevention, and isolation (identification for the failed location).

This article focuses on the various types of corrosion-related failure mechanisms and their effects on passive electrical components. The types include halide-induced corrosion, organic-acid-induced corrosion, electrochemical metal migration, silver tarnish, fretting, and metal whiskers. The passive electrical components include resistors, capacitors, wound components, sensors, transducers, relays, switches, connectors, printed circuit boards, and hardware.

This article focuses on the process design set-up procedure for brazing and soldering. It provides a detailed account of the types of base metals that can be joined by these processes, and reviews the factors to be considered to enhance the joint design. Criteria for selection of the right induction heating equipment to carry out the brazing or soldering operation are also provided. The article describes the types of brazing filler metals and joint designs. It also presents the types of inspection methods, namely, mechanical and visual, used to determine the quality of the brazed joint. Important considerations for the automation of induction-heated brazing applications are also discussed. The article concludes by emphasizing the need for documenting an in-control process which is a vitally important reference for questions or problems arising in the machine settings or part quality.

This article focuses on the isothermal fatigue of solder materials. It discusses the effect of strain range, frequency, hold time, temperature, and environment on isothermal fatigue life. The article provides information on various isothermal fatigue testing methods used to assess solder joint reliability. These include the accelerated thermal cycling test and isothermal mechanical deflection system test.

Vapor-phase soldering is a process of condensation heating in which the product prepared for soldering is passed through or into a layer of saturated vapor. This article provides an overview of the soldering process with emphasis on its applications and the equipment used.

Tin is a soft, brilliant white, low-melting metal that is most widely known and characterized in the form of coating. This article discusses the primary and secondary production of tin and explains the uses of tin in coating, namely tinplating, electroplating, and hot dip coatings. It presents a short note on pure (unalloyed) tin and uses of tin in chemicals. The article also covers the compositions and uses of tin alloys which include solders, pewter, bearing alloys, alloys for organ pipes, and fusible alloys. It goes on to discuss the other alloys containing tin including battery grid alloys, type metals, copper alloys, dental alloys, cast irons, titanium alloys, and zirconium alloys. Finally, it presents a short note on the applications of tin powder and corrosion resistance of tin.

Electrodeposition of tin alloys is used to protect steel against corrosion or wear, to impart resistance to etching, and to facilitate soldering. This article focuses on the compositions, operating conditions, advantages, and limitations of methane sulfonic acid plating solutions and fluoborate plating solutions for tin-lead. It briefly describes the solution compositions and operating conditions of tin-bismuth, tin-nickel, and tin-zinc.

Before the quality of a soldered joint can be evaluated, the components that are required for the formation of a good soldered joint should be reviewed. These components are solder, applied heat, and solderable surface. This article discusses each of these as well as the end-use requirements and joint configurations required for the formation of a good soldered joint. It focuses on the visual, automatic, and destructive inspection techniques for determining overall joint quality.

This article presents a table that lists the linear thermal expansion of selected metals and alloys. These include aluminum, copper, iron, lead, magnesium, nickel, tin, titanium, and zinc and their alloys. Thermal expansion is presented for specific temperature ranges.

Tin is produced from both primary and secondary sources. This article discusses the chemical compositions, production, properties, microstructure and applications of tin and tin alloys. The major tin alloys discussed here are tin-antimony-copper alloy (pewter), bearing alloy, solder alloy and other alloys containing traces of tin. Data on tin consumption in the United States is presented graphically.

This article contains a table that lists the thermal conductivity of selected metals and alloys near room temperature. These include aluminum and aluminum alloys; copper and copper alloys; iron and iron alloys; lead and lead alloys; magnesium and magnesium alloys; nickel and nickel alloys; tin and tin alloys; titanium and titanium alloys; zinc and zinc alloys; and pure metals.

This article discusses the properties, primary and secondary production, product forms and applications of various grades of lead and lead-base alloys with the aid of several tables and illustrations. It lists the Unified Numbering System (UNS) designations for various pure lead grades and lead-base alloys grouped according to nominal chemical composition. The properties of lead that make it useful in a wide variety of applications are also discussed. The largest use of lead is in lead-acid storage batteries. Other applications include ammunition, cable sheathing, cast products such as type metals, terneplate, foils, and building construction materials. Lead is also used as an alloying element in steel and in copper alloys to improve machinability. The article concludes with information on the principles of lead corrosion, corrosion resistance of lead in water, atmospheres, underground ducts, soil and chemicals.

This article is an atlas of fractographs that helps in understanding the causes and mechanisms of fracture of electronic materials, including L-shaped electronic flat pack, transistor base lead, ohmic contact window, and brush/slip ring assembly. The fractographs illustrate the atomic oxygen environment exposure effect, solar cell interconnect, integrated circuit defects, and fatigue failure of these materials.

This article presents an introduction to brazing, including information on its mechanics, advantages, and limitations. It reviews soldering with emphasis on chronology, solder metals, and flux technology. The article also provides useful information on mass, wave, and drag soldering. It presents a table which contains information on the comparison of soldering, brazing, and welding.

Fabrication of wrought stainless steels requires use of greater power, more frequent repair or replacement of processing equipment, and application of procedures to minimize or correct surface contamination because of its greater strength, hardness, ductility, work hardenability and corrosion resistance. This article provides a detailed account of such difficulties encountered in the fabrication of wrought stainless steel by forming, forging, cold working, machining, heat treating, and joining processes. Stainless steels are subjected to various heat treatments such as annealing, hardening, and stress relieving. Stainless steels are commonly joined by welding, brazing, and soldering. The article lists the procedures and precautions that should be instituted during welding to ensure optimum corrosion resistance and mechanical properties in the completed assembly.

Soldering involves heating a joint to a suitable temperature and using a filler metal (solder) that melts below 450 deg C (840 deg F). Beginning with an overview of the specification and standards and applications, this article discusses the principal levels and effects of the most common impurity elements in tin-lead solders. It describes the various processes involved in the successful soldering of joints, including shaping the parts to fit closely together; cleaning and preparing the surfaces to be joined; applying a flux; assembling the parts; and applying the heat and solder.

Soldering represents the primary method of attaching electronic components, such as resistors, capacitors, or packaged integrated circuits, to either printed wiring board whose defects is minimized by consideration of proper PWB design, device packages, and board assembly. This article discusses the categories that are most important to successful electronic soldering, namely, solders and fluxes selection, nature of base materials and finishes, solder joint design, and solderability testing.

Soldering is defined as a joining process by which two substrates are bonded together using a filler metal with a liquidus temperature. This article provides an overview of fundamentals of soldering and presents guidelines for flux selection. Types of fluxes, including rosin-base fluxes, organic fluxes, inorganic fluxes, and synthetically activated fluxes, are reviewed. The article describes the joint design and precleaning and surface preparation for soldering. It addresses some general considerations in the soldering of electronic devices. Soldering process parameters, affecting wetting and spreading phenomena, such as temperature, time, vapor pressure, metallurgical and chemical nature of the surfaces, and surface geometry, are discussed. The article also describes the applications of furnace soldering, resistance soldering, infrared soldering, and ultrasonic soldering. It contains a table that lists tests commonly used to evaluate the solderability properties of selected soldered components.

This article describes the allotropic modification and atmospheric corrosion of pure tin. Corrosion of pure tin due to oxidation reaction, and reaction with the other gases, water, acids, bases, and other liquid media, is discussed. The article provides information on corrosion behavior on soft solders, pewter, bearing alloys, tin-copper alloys, and tin-silver alloys. It reviews the influence of corrosion on immersion tin coating, tin-cadmium alloy coatings, tin-cobalt coatings, tin-copper coatings, tin-lead coatings, tin-nickel coatings, and tin-zinc coatings. The general properties and corrosion resistance of tinplate are summarized. The article also describes the methods of corrosion testing of coatings; these include an analysis of coating thickness measurements, porosity and rust resistance testing, solderability test, and specific special tests.

This article begins with a schematic illustration of a eutectic system in which the two components of the system have the same crystal structure. Eutectic systems form when alloying additions cause a lowering of the liquidus lines from both melting points of the pure elements. The article describes the aluminum-silicon eutectic system and the lead-tin eutectic system. It discusses eutectic morphologies in terms of lamellar and fibrous eutectics, regular and irregular eutectics, and the interpretation of eutectic microstructures. The article examines the solidification of a binary alloy of exactly eutectic composition. It concludes with a discussion on terminal solid solutions.