Soldering technology has been used in applications ranging from the packaging of integrated circuit chips to the fabrication of industrial heat exchangers and consequently in structural or electronic applications. This article provides information on various soldering parameters, including types of solder alloy in terms of selection process; selection of substrate base material; flux selection based on adequate wettability by the solder; solder joint assembly; combined substrate, solder, and flux properties; and manufacturing procedures. Each of these parameters is explored using examples of both structural and electronic applications. The article concludes with a discussion on the environmental, safety, and health issues to be considered during soldering.

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).

Torch soldering utilizes a fuel gas flame as the heat source in the soldering process to produce a leak-tight assembly with some degree of mechanical strength. This article describes the advantages, limitations, and applications of torch soldering. It reviews the equipment used and the basic heating techniques required for the soldering.

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.

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.

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.

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.

This article focuses on the design considerations and process parameters critical to the successful implantation of wave soldering on printed circuit boards. The design considerations include the through-hole technology and the surface-mount technology. The article presents information on process parameters, which can be divided into three groups: the fluxing operation, solder wave properties, and process schedule. It provides information on various solder defects.

Hot gas soldering is a process that is commonly used in applications where the workpiece thermal mass is small and the melting temperature of the solder is relatively low. This article describes the characteristics of hot gas heating that are critical to its effectiveness in soldering. These characteristics include the focus of gas flow, gas flow rates (velocity and volume), gas temperature, and typical gas media. The article explains the thermal profile of a component being soldered and the temperature across adjacent components, which helps to understand time-temperature relationship. It concludes with a discussion on reliability concerns and processing concerns when using hot gas soldering in electronics assembly.

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.

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 factors considered in the analysis of brazeability and solderability of engineering materials. These are the wetting and spreading behavior, joint mechanical properties, corrosion resistance, metallurgical considerations, and residual stress levels. It discusses the application of brazed and soldered joints in sophisticated mechanical assemblies, such as aerospace equipment, chemical reactors, electronic packaging, nuclear applications, and heat exchangers. The article also provides a detailed discussion on the joining process characteristics of different types of engineering materials considered in the selection of a brazing process. The engineering materials include low-carbon steels, low-alloy steels, and tool steels; cast irons; aluminum alloys; copper and copper alloys; nickel-base alloys; heat-resistant alloys; titanium and titanium alloys; refractory metals; cobalt-base alloys; and ceramic materials.

Brazing and soldering are done at temperatures below the solidus temperature of the base material but high enough to melt the filler metal and allow the liquid filler metal to wet the surface and spread into the joint gap by capillary action. This article discusses the common advantages of both brazing and soldering. It describes the brazing and soldering of cast irons, as well as the selection of brazing filler material. The article discusses various brazing methods: torch brazing, induction brazing, salt-bath brazing, and furnace brazing. It concludes with information on the application examples of brazing of cast iron.

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.

Furnace soldering (FS) encompasses a group of reflow soldering techniques in which the parts to be joined and preplaced filler metal are put in a furnace and then heated to the soldering temperature. This article describes three reflow soldering techniques in surface-mount technology, namely, vapor-phase reflow, area conduction, and infrared heating. These three techniques are considered as mass reflow techniques, because all of the solderable interconnections on the surface of a printed wiring board (PWB) assembly are brought through the reflow heating cycle simultaneously. The article explains four regions of reflow profile, namely, preheat (prebake), preflow (soak), reflow, and cooldown. It concludes with a description on the bare copper assembly process, which is carried out in the inert atmosphere.

Joining is key to the manufacture of large or complex devices or assemblies; construction of large and complex structures; and repair of parts, assemblies, or structures in service. This article describes the three forces for joining: physical, chemical, and mechanical. It provides an overview of the joining processes, namely, mechanical fastening, integral attachment, adhesive bonding, welding, brazing, and soldering. The article concludes with information on the various aspects of joint design and location that determine the selection of a suitable joining method.

This article focuses on the various criteria considered in the selection of product forms, joint types, solders, and filler metals for brazing and soldering of base material components.

Corrosion is often thought of as rusting, the process of deterioration undergone by a metal when it is exposed to air or water. This article provides the fundamentals of joints corrosion and primarily addresses the various forms of corrosion observed in brazed and soldered joints and their causes. It describes the role of proper brazing procedures in controlling corrosion. The article concludes with information on the corrosion resistance of various brazing alloy systems.

This article explains how to design a joint or conduct a joining process so that components can be produced most efficiently and without defects. The joining processes include mechanical fastening, adhesive bonding, welding, brazing, and soldering. The article discusses the selection and application of good design practices based on the understanding of process-related manufacturing aspects such as accessibility, quality, productivity, and overall manufacturing cost. It provides several examples of selected parts and joining processes to illustrate the advantages of a specific design practice in improving manufacturability.