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A solder is a fusible metal alloy with a melting point or melting range of 90 to 450 °C (200 to 840 °F), used in a process called soldering where it is melted to join metallic surfaces. A fusible alloy, usually Eutectic Alloy is capable of being fused, as well as being liquefied by heat An alloy is a Solid solution or Homogeneous mixture of two or more elements, at least one of which is a Metal, which itself has The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 Soldering is a process in which two or more Metal items are joined together by melting and flowing a filler metal into the joint the filler metal having a relatively low It is especially useful in electronics and plumbing. Electronics refers to the flow of charge (moving Electrons through Nonmetal conductors (mainly Semiconductors, whereas electrical Plumbing, from the Latin plumbum for Lead, is the skilled trade of working with pipes, tubing and Plumbing fixtures for Alloys that melt between 180 and 190 °C are the most commonly used.

The word solder comes from the Middle English word soudur, via Old French solduree and soulder, from the Latin solidare, meaning '‘to make solid’'. Middle English is the name given by Historical linguistics to the diverse forms of the English language spoken between the Norman invasion of Old French was the Romance Dialect continuum spoken in territories which span roughly the northern half of modern France and parts of modern Belgium Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. In North America "solder" is pronounced with a silent L. Solder can contain lead and or flux but in most cases solder is now lead free.

Desoldering a contact and a wire attached with solder.
Desoldering a contact and a wire attached with solder.

Contents

Lead solder

Tin/lead solders are commercially available with tin concentrations between 5% and 70% by weight. Tin is a Chemical element with the symbol Sn (stannum and Atomic number 50 Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly The greater the tin concentration, the greater the solder’s tensile and shear strengths. Tensile strength \sigma_{UTS} or S_U is the Stress at which a material breaks or permanently deforms Shear strength in Engineering is a term used to describe the strength of a material or component against the type of yield or Structural failure where the At the retail level, the two most common alloys are 60/40 Sn/Pb and 63/37 Sn/Pb used principally in electrical work. Tin is a Chemical element with the symbol Sn (stannum and Atomic number 50 Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly The 63/37 ratio is notable in that it is a eutectic mixture, which means:

  1. It has the lowest melting point (183 °C or 361. 4 °F) of all the tin/lead alloys; and
  2. The melting point is truly a point — not a range


At an eutectic composition, the liquid solder solidifies as a eutectic, which consists of fine grains of nearly pure lead and nearly pure tin phases, but in no way is it an intermetallic, since there are no tin/lead intermetallics, as can be seen from a tin/lead equilibrium diagram. [1]

In plumbing, a higher proportion of lead was used. This had the advantage of making the alloy solidify more slowly, so that it could be wiped over the joint to ensure watertightness. Although lead water pipes were displaced by copper when the significance of lead poisoning began to be fully appreciated, lead solder was still used until the 1980s because it was thought that the amount of lead that could leach into water from the solder was negligible. Lead poisoning (also known as saturnism, plumbism, or painter's colic) is a medical condition caused by increased levels of the metal Lead in Since even small amounts of lead have been found detrimental to health, lead in plumbing solder was replaced by copper or antimony, with silver often added, and the proportion of tin was increased (see Lead-free solder below). Copper (ˈkɒpɚ is a Chemical element with the symbol Cu (cuprum and Atomic number 29 Antimony (IPA (Received Pronunciation, /ˈæntɪmoʊni/ (US is a Chemical element with the symbol Sb (stibium meaning "mark" and Silver (ˈsɪlvɚ is a Chemical element with the symbol " Ag " (argentum from the Ancient Greek: ἀργήντος - argēntos gen

Hard solder

As used for brazing, is generally a copper/zinc or copper/silver alloy, and melts at higher temperatures. Brazing is a joining process whereby a Filler metal or Alloy is heated to melting temperature above - or by the traditional definition in the United States Zinc (ˈzɪŋk from Zink is a Metallic Chemical element with the symbol Zn and Atomic number 30

In silversmithing or jewelry making, special hard solders are used that will pass assay. An assay is a procedure where a property or concentration of an Analyte is measured They contain a high proportion of the metal being soldered and lead is not used in these alloys. These solders also come in a variety of hardnesses, known as 'enamelling', 'hard', 'medium' and 'easy'. Enamelling solder has a high melting point, close to that of the material itself, to prevent the joint desoldering during firing in the enamelling process. In a discussion of Material science, enamel (or vitreous enamel or porcelain enamel in U In Electronics, desoldering is the removal of Solder and components from a circuit for Troubleshooting, repair purposes and to salvage components The remaining solder types are used in decreasing order of hardness during the process of making an item, to prevent a previously soldered seam or joint desoldering while soldering a new joint. Easy solder is also often used for repair work for the same reason. Flux or rouge is also used to prevent joints desoldering. In Metallurgy, a flux is a chemical cleaning agent which facilitates Soldering, Brazing, and Welding by removing Oxidation from

Silver solder is also used in manufacturing, when there is a need to join metal parts that cannot be welded. Welding is a fabrication process that joins materials usually Metals or Thermoplastics by causing coalescence. The alloys used for these purposes contain a high proportion of silver (up to 40%), and may also contain toxic cadmium. Cadmium (ˈkædmiəm is a Chemical element with the symbol Cd and Atomic number 48

Flux core solder

A tube of multicore electronics solder used for manual soldering - the flux is contained in five cores within the solder itself
A tube of multicore electronics solder used for manual soldering - the flux is contained in five cores within the solder itself

Solder often comes pre-mixed with, or is used with, flux, a reducing agent designed to help remove impurities (specifically oxidised metals) from the points of contact to improve the electrical connection. In Metallurgy, a flux is a chemical cleaning agent which facilitates Soldering, Brazing, and Welding by removing Oxidation from Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state For convenience, solder is often manufactured as a hollow tube and filled with flux. Most cold solder is soft enough to be rolled and packaged as a coil, making for a convenient and compact solder/flux package. The two principal types of flux are acid flux, used for metal mending, and rosin flux, used in electronics, where the corrosiveness of the vapours that arise when acid flux is heated could damage components. Due to concerns over atmospheric pollution and hazardous waste disposal, the electronics industry has been gradually shifting from rosin flux to water-soluble flux, which can be removed with deionised water and detergent, instead of hydrocarbon solvents. Purified water is water from any source that is physically processed to remove impurities

Lead-free solder

A coil of lead-free solder wire
A coil of lead-free solder wire

On July 1, 2006 the European Union Waste Electrical and Electronic Equipment Directive (WEEE) and Restriction of Hazardous Substances Directive (RoHS) came into effect prohibiting the intentional addition of lead to most consumer electronics produced in the EU. "July 1st" redirects here For the Ayumi Hamasaki song see H (song. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. The European Union ( EU) is a political and economic union of twenty-seven member states, located primarily in The Waste Electrical and Electronic Equipment Directive (WEEE Directive is the European Community directive 2002/96/EC on waste electrical and electronic equipment The Directive on the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment 2002/95/EC ( / commonly referred to as the Restriction of Hazardous No such legislation is in place in the United States, or other countries, however manufacturers may receive tax benefits by reducing the use of lead-based solder. Lead-free solders in commercial use may contain tin, copper, silver, bismuth, indium, zinc, antimony, and traces of other metals. Bismuth (ˈbɪzməθ is a Chemical element that has the symbol Bi and Atomic number 83 Indium (ˈɪndiəm is a Chemical element with chemical symbol In and Atomic number 49 Zinc (ˈzɪŋk from Zink is a Metallic Chemical element with the symbol Zn and Atomic number 30 Antimony (IPA (Received Pronunciation, /ˈæntɪmoʊni/ (US is a Chemical element with the symbol Sb (stibium meaning "mark" and Most lead-free replacements for conventional Sn60/Pb40 and Sn63/Pb37 solder have melting points from 5–20 °C higher, though solders with much lower melting points are available.

Drop-in replacements for silkscreen with solder paste soldering operations are available. Minor modification to the solder pots (e. g. titanium liners and/or impellers) used in wave-soldering operations may be desired to reduce maintenance costs associated with the increased tin-scavenging effects of high tin solders. The properties of lead-free solders are not as thoroughly known and may therefore be considered less reliable in select applications, e. g. Hi-rel aerospace and life-critical medical. "Tin Whiskers" were a problem with early electronic solders which were coincidentally lead-free, and lead was initially added in part to eliminate them. Metal whiskering is a Crystalline metallurgical phenomenon involving the spontaneous growth of tiny filiform hairs from a Metallic surface These problems are negligible in modern alloys, however, except in hi-rel military, aerospace-satellite and life-critical medical applications.

Different elements serve different roles in the solder alloy:

Solder fumes

The fumes produced from soldering operations are potentially dangerous. The process may generate a fume which is a combination of lead oxide (from lead based solder) and colophony (from the solder flux). Rosin, formerly called colophony or Greek pitch ( Pix græca) is a solid form of Resin obtained from Pines and some other Plants Each of these constituents has been shown to be hazardous.

See also

External links

Soldering is a process in which two or more Metal items are joined together by melting and flowing a filler metal into the joint the filler metal having a relatively low Solder paste (or solder cream) is used for connecting the terminations of the IC packages with that of land patterns on the PCB A solder sucker is a device which is used to remove solder from a Printed circuit board (PCB as opposed to a Desoldering bulb or Solder wick. Solderability defines whether a Solder can perform as intended in-service under normal fabrication methods or processes A soldering gun is a tool for soldering metals using lead-tin-based Solder to achieve a highly conductive contact A soldering iron is a device for applying heat to melt Solder for attaching two metal parts Welding is a fabrication process that joins materials usually Metals or Thermoplastics by causing coalescence. Brazing is a joining process whereby a Filler metal or Alloy is heated to melting temperature above - or by the traditional definition in the United States

Dictionary

solder

-noun

  1. Any of various alloys, often of tin and lead, that are used to join small pieces of metal together

-verb

  1. To join with (or as if with) solder
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