How do you choose filler metal for brazing?

When selecting a braze filler metal important factors to consider are:

1. The base metals being joined.
2. The brazing process to be used.
3. The brazing temperature.
4. How the braze filler metal is applied to the joint.
5. The design of the joint.
6. What form the braze filler is available in.
7. The environment and service of the joint.

Can alloy be brazed?

Brazing alloys can be considered as a sort of metallic ‘high-temperature glue’. High-temperature brazing alloys are based on gold, nickel and copper and are often used for joining CMC to cobalt or nickel-based super-alloys.

What is a brazing alloy?

Brazing is a metal joining process whereby a filler metal is heated above the melting point and distributed between two or more close fitting parts by capillary action. In general, braze alloys are made up of 3 or more metals to form an alloy with the desired properties.

Which flux is commonly used in brazing?

White flux is useful for brazing copper, brass, steel, stainless steel, and nickel alloys. It has an active temperature range of 1050 -1600°F (565 – 870°C).

Can I braze aluminum with a propane torch?

Introduction: How to Solder Aluminum. A torch with more of a pin point would do better. In either case if you have a propane torch and brazing rods you can weld aluminum. All this can be found at your local hardware store.

Do you need flux to braze aluminum?

Aluminum braze flux is required in all aluminum brazing operations. Aluminum brazing fluxes consist of various combinations of fluorides and chlorides and are supplied as a dry powder. For torch and furnace brazing, the flux is mixed with water to make paste.

What is brazing alloy made from?

Brazing brass, on the other hand, is a specific type of filler material made of brass, which is an alloy from copper and zinc. Brass works well with cast iron and is mostly a general-purpose filler used for day-to-day brazing needs. It is relatively ductile and has high vapour pressure because of the volatile zinc.

Which materials should not braze you?

Metals You Shouldn’t Dip Braze Heating metals, like silver or gold, to such high heat requires a lot of precision. It’s more common for these metals to be soldered rather than brazed. Gold and silver can handle the lower heat better, and soldering can still give a good bond, even if it’s not as strong.

What temp is required for brazing?

Most brazing processes run at temperatures between 800°F and 2,000°F. For a strongest braze joint, the metals that are being joined together need to be at close to the same temperature. Slow heat cycles generally produce better results than fast heat cycles.

What do you need to know about brazing alloys?

Braze and Brazing Alloys Information. Brazing is a process used to adjoin metal materials together by the use of a consumable metal filler. This process is similar to soldering, except temperatures required to melt the filler metal are higher (above 840° F).

What’s the difference between brazing and soldering aluminium?

Soldering is a similar process to brazing, except that the process temperatures are lower. Traditionally, brazing and soldering of aluminium are distinguished from each other in the following manner:  Soldering: T < 450 °C  Brazing: T > 450 °C. Brazing produces excellent joints, in particular when joining thin-walled, compact parts.

What’s the best way to braze a metal?

Many methods exist to accomplish brazing, but the most important consideration is the efficient transfer of heat to filler materials without damaging the base metal. Depending upon the application, the aesthetic and volume of brazing may be considered as well. Heat is applied by an oxyfuel gas torch.

How is brazing used to distribute molten filler?

For more on the uses of brazing, watch this video. Brazing, as we’ve seen, uses the principle of capillary action to distribute the molten filler metal between the surfaces of the base metals.