🗊Презентация Припої. Загальні властивості

Scientific and technical work on the topic: "Solders. General Properties " Execute: Students gr. CS-17-1 / 9 Dunaev Vlad Oleg Podhibalov Yurkov Nikita Teacher of physics: Pyhtina OI

Solders. General properties Solder- material used in Peitz connecting pieces and has a melting point lower than the metal connectors. Apply alloys of tin, lead, cadmium, copper, nickel, silver and others. Solders are issued in the form of pellets, rods, wire, powder, foil, pastes and mortgage details. Pike engaged to create a mechanically strong (usually sealed) joint, or for electrical contact with a small transitional resistance. At the junction of Peitz solder is heated above its melting temperature. Since the solder has a melting temperature lower than the melting point of connecting metals making up the parts that are connected, it melts, while metal parts remains solid.

At the point of contact of the molten solder and solid metal held various physical and chemical processes. Solder wets metal spreads over it and fills the gap between the parts. The components of solder diffuses into the base metal and the metal can sometimes partially dissolve in the solder, resulting in an intermediate layer, which after hardening connecting parts into one. Choose based solder physicochemical properties of metals are joined (eg, melting point) required mechanical strength of the junction, its corrosion resistance and cost. When Peitz live parts must take into account the specific conductivity of the solder.

Solder Tin-lead: specifics and characteristics Among all existing alloys for solder widely used tin-lead solder. Most actively it is used for soldering: electrical industry products, radio electronics; automation systems for various applications; engineering and automotive products; tube production; refrigeration; copper pipes; surfaces to be galvanizing; electric coils. Made Tin-lead solders GOST 21931-76 and GOST 21930-76. This category refers to solders "soft" and marked with the abbreviation POS + additional elements and digital code that indicates the percentage of tin.

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Conclusion For brazing stainless steels, heat, telescopic pipe joints in the food industry, soldering tools with speed steel, face cuts, as well as Peitz cellularpanels in aircraft and missile technology. It is advisable to replace expensive solder, which is part of the silver DPL 72 DPL 45 to use high-temperature solders. The general trend for today - the refusal of welding in favor of high-temperature soldering. This provides advantages - the strength of the weld strength not lower soldering products, a small section of the seam, temperature solder 50at-200atWith less than rozpayky temperature (operating temperature). Average temperature solders usually made of copper. The main elements that are added to the composition of solder - a nickel and phosphorus. This systemCu-Ni-P is basic. It adds tin, indium, germanium, zinc in varying amounts depending on the composition of products. To the average temperature fast ice are also in place, silver and gold-fast ice systemsZn, Al, Ge with admixtures of tin, bismuth, indium in small quantities. The most common solders assortment - powder, depending on the composition of the solder is mixed with flux, often brown, but recent high stocks solders based on nickel and iron produced in the form of tape thickness is 20-40mkm. These solders are consideredsamoflyusuyuchymyDue to additives of silicon and boron, these elements are depressants. Use tape assortment enables fitting solder of any configuration with uniform thickness along the length seam.

As a result of calculations we have: the main components of solder, which is considered a STD is tin ~ 54%, lead ~ 46%. This alloy brand POS-60. As a result of calculations we have: the main components of solder, which is considered a STD is tin ~ 54%, lead ~ 46%. This alloy brand POS-60. Based solders Tin-lead alloys widely used in the past and is still produced. They are especially useful in manual soldering. Hand soldering soft solders by using a soldering iron or blowtorch (t = 180 ~ 200atC), electrical contacts and electrical wires with copper. Tin-lead solders, also called "soft" examined with significant concentrations of tin from 5 to 70%. The higher concentration of tin, the solder becomes higher in its ultimate tensile strength and shear. When soldering circuits using solder POS-60 (60/40 tin / lead,Sn/Pb) That melts at t= 188atWITH. Adding tin material which is more expensive than lead improves the wetting properties of the alloy prypiynoho as wetting ability of the lead is low.