Soldering of brass has its own characteristics due to evaporation of hot zinc and the formation of surface oxide film. In the brass, which contain up to 15% of zinc oxide film consists of concatenated particles of ZnO and CuO. In copper alloys containing a large quantity of zinc, the oxide layer consists mainly of ZnO, which is more difficult to remove than the oxide of copper.
Fluxes and solders
In low-temperature soldering lead-tin, etc. solder needed to be removed from the surface of brass oxide film. Use rosin-alcohol or more active fluxes. For example, during the soldering process the brass brands L63, LS59−1-1 apply fluxes with zinc chloride basis with additives. Brass unlike copper is much worse soluble in molten lead-tin solders. Thus, in the soldering process are slow growing intermetallic layers has a positive influence on the mechanical properties of the solder joint. L63 obtained when soldering lead-tin solder joints have lower strength than copper — in the same conditions. For example, the tensile strength of brazed tin plated copper compounds butt is 90 MPa, the brass — no more than 59 MPa.
When soldering brass, with a high content of copper used silver solders brands: Psr40, Psr72, Psr45, ПСр12, Psr25, and copper-phosphorous, brass, and brass with a low melting point. When soldering brass, with a high content of zinc (L68, L63) use solder Psr40. For them, the phosphorous solder, as the solder viscoplastic connection. This can be explained by the fact that the soldering seam formed very brittle phosphide of zinc.
For those compounds, which are not subject to dynamic and vibration loads, use solders PMC48 and PMC36. During brazing, copper-phosphorous, and silver solders brass begins to rapidly dissolve. Therefore, to reduce contact of the solid metal and liquid solder should be soldered with a high rate of heating. Brass brands L63 intensively dissolves in the solder Psr45, Psr40 and Psr15 and much less — in solders Psr50kd and Psr37,5.
Parts made of brass can be soldered at temperatures of 850−870°C and in salt baths. To improve the wicking of solder into the solution baths in the gap add 4−5% of a flux, which contains borax or potassium torobert. In the heating process parts in furnaces, and the flame of the gas burners is also oxidation and evaporation of zinc, thus deteriorating the spreading of the solders. During soldering of brass with the burner fails to reduce slightly reducing flame oxidation and evaporation of zinc. Porosity in the joints of the soldering decreases.
To buy, price
OOO «Electrocentury-steel» implements articles of brass deformed and foundry marks.erokom range at the best price. Supply fluxes and solders of different brands. All products are certified. The quality meets the requirements of GOST and international standards. The timing of orders is minimal. The price depends on order volume and additional conditions of supply. Wholesale customers enjoy preferential discounts.