General Characteristics

There is an alphiated layer on the titanium surface which is saturated with atmospheric gases. Before start of soldering such layer must be removed by sandblasting or pickling in _HNO3 (20-20 ml) and HCl (30-40 ml) solution per 1 l of water. The etching time is 5 to 10 min at 20 °C. After this treatment there is still an oxide thin film on the titanium surface that prevents the wetting of the solder surface. As a rule, soldering of titanium and titanium alloys is performed in argon or vacuum, thoroughly purified from nitrogen impurities, water vapors and oxygen. Therefore, titanium brazing is generally performed at t° from 800 to 900 °C. This ensures quick cleaning of its surface and good wetting of the solder. At higher temperatures soldering of titanium alloys is rarely carried out, since at prolonged heating above 900 ° C the tendency to increase the grain, as well as worsen plastic properties. It is the hydrogen in the metal that reduces ductility. Hydrogen is removed in the process of brazing or when heated to 900 ° C in a vacuum at a pressure of 0.01 Pa. Therefore titanium brazing in a vacuum is preferable to brazing in a neutral atmosphere.

Intermetallides

When selecting solder, brazing method and mode, it should be remembered that titanium is capable of forming brittle intermetallides in the brazed seam with all the elements that are included in the solders. That is why silver is often used as a solder base. It forms the least brittle intermetallic compounds with titanium.

Low-temperature brazing alloys

Soldering titanium with tin-lead and other low-temperature brazing alloys is quite rare. In this case titanium is electrolessly or chemically nickel-coated before the brazing process. To increase the bonding of nickel and titanium the parts are heated to t° 250 °C for an hour. Then it is brazed with the same fluxes and solders as for pure nickel. Titanium and its alloys can also be brazed with low-temperature brazing alloys after being pre-coated with silver, copper or tin. To tin the workpiece prepared for soldering, it is quickly dropped into a heated to t° 700 ° C tin for 10-20 minutes. Using flux, which includes chloride tin, you can also cover titanium with tin.

Buy, price

Evek GmbH sells rolled metal products at the best price. It is formed taking into account the rates at the LME (London metal exchange) and depends on the technological characteristics of production without additional costs. We supply semi-finished products from titanium and its alloys in wide assortment. All batches have quality certificate for compliance with standards requirements. With us you can buy in bulk the most various products for large-scale productions. The wide choice, exhaustive consulting of our managers, reasonable prices and timely delivery determine the face of our company. There is a system of discounts for wholesale purchases.