What should we choose – copper braze or silver solder? This question has always been a dilemma for many carbide burr manufacturers. Moreover, many customers also seek information on this query.
Well, brazing is the process of joining two or more metals by using a melted material. The melting material should have a lower melting point than the joining metals. Welding and soldering serve in different jobs depending on the demand.
Likewise, silver soldering is also the process of joining two metals using a melted material. Silver soldering comes in three major types, i.e., easy, medium, and complex, depending on the melting point.
The main disparity between soldering and brazing is the melting point of filler metals. Brazing uses higher temperatures as compared to soldering. Usually, brazing metals melt above 842ºF.
So, let’s find out the notable differences between copper braze and silver solder. What’s more, we will also help you choose between these processes.
Things to Consider When Selecting Between Copper Braze or Silver Solder?
There are various vital factors to contemplate when choosing between soldering and brazing. Some of the factors that you will need to factor in are the temperature and the service loading. Brazing and soldering are similar, but the level of temperatures yield the difference.
It’s always advisable to choose a filler method that is most suitable for your assemblies. When it comes to carbide brazing, it’s essential to choose a suitable filler metal too. Most companies prefer using copper brazing with a combination of carbide blanks holes.
1. Temperature Assemblies
High temperatures easily damage delicate materials, and thus brazing will not be favorable. Higher temperatures make the oxidation of filler materials and the base a significant problem. And this is generally the case when using brazing.
Delicate materials that do not need high temperatures, thus, need soldering materials. That’s because soldering uses lower temperatures. Brazing needs high heat that may cause severe damage to the delicate materials.
2. Corrosion Resistance
Soldered joints are generally more liable to degradation due to oxidation caused by chemicals. Chemicals such as salt react with the surfaces hence resulting in corrosion. It’s a different case with brazed joints.
Metals that have joined by soldering are more potent than the solder used. It means under too much pressure and stress, they start weakening at the joints. In short, it means that a soldered assembly has less strength and lower fatigue resistance.
In such cases, you may want to concede using brazing to join the metals and not soldering.
3. Strength Requirements
Sometimes you may want to join two or many materials with a less rigid bond. In such cases, using soldering will give you the desired bond than brazing. Soldering applies well to instances where the parts joined need to be flexible. For example, microelectronic components are delicate. Thus, a rigid attachment would not be necessary.
Using brazing bonding in cases like this may cause severe damage to the pieces you are bonding. Brazing works better for a strong contender for a permanent metal-to-metal joint. Soldering can also offer a permanent bond but not as strong as a brazed bond.
4. Thermal Expansion
Soldering uses lower melting temperatures and lower temperatures with lower distortion upon cooling. Moreover, soldering also uses softer metals which permit accommodation of CTE mismatch. That’s because soldering is less sensitive to thermal expansion mismatch.
5. Wettability of the Filling Material
Wettability is essential when making joints between carbides. That’s because it strengthens the bonds between the carbide, base, and filler. There are various filling materials used for carbide joining. One of the commonly used with excellent wetting capabilities is BAG-7, 56% silver with Tin. But the filer makes weak joints, and joint failures can occur.
BAG- 22, 49% silver with manganese is also commonly used strong filler but a bit gummy with its flow.
6. Cost of the Process
The cost of the filler materials can be a significant factor, especially when working on a budget. Filler materials also cost according to the purposes they serve. Solid and durable filers may be expensive compared to weak ones.
Soldering is less costly as compared to brazing. Besides, soldering also uses less expensive filler materials. Lower temperatures also mean it costs less to melt the filler materials. There is less post-clean-up process due to the low joining temperatures. As a result, this reduces the costs of the whole process altogether.
Now, we will differentiate both these processes based on the following points.
- Definition
- Temperature
- Advantages
- Disadvantages
So, let’s begin!
What Is Copper Braze?
Definition
Copper brazing is the process of joining two materials together using copper brazing. It is when two tube sections of copper metal join using filler materials. The filler metal acts as the joining agent between the two metals.
Temperature
Brazing is reliable for joining carbides to other base materials like shanks. A material that is a brazing filler melts above 842°F or 450C°C. Likewise, the temperature of welding ranges between 1200-1220℃.
The fillers in the brazing method melt using very high temperatures. The process involves heating a filler alloy at very high temperatures and then melting the filler into the joint. But, the filler alloy should have a lower melting point than the metals.
Advantages
The advantage of using copper brazing for joining is that it offers a more secure and stronger bond. Liquid flux is often used to promote the wetting of the metal parts letting the filler flow over so quickly. Typically, fluxes are organometallic or higher temperature salts that are acidic when melted. The acidic nature of the Fluxes reduces forming of oxides on the copper material.
Disadvantages
Brazing can be disadvantageous because of the very high temperatures involved. These high temperatures can easily damage the material you are trying to join. The high temperatures also make it a problem for the oxidation of the filler materials and the base.
What Is Silver Solder?
Definition
Silver soldering is a process similar to copper brazing. That’s because this process also uses filler melted materials. One significant difference between copper brazing and silver soldering is the temperatures.
Temperature
Higher temperatures apply on copper brazing and lower temperatures on silver solders. Silver solders associate with two terms which are hard solder and soft solder.
Silver Solder fillers melt at lower temperatures as compared to copper brazing fillers. The temperatures that melt silver solder fillers are low. Moreover, here the welding temperature is shallow, which ranges between 820 to 850℃. That is what makes a significant difference between copper brazing and silver soldering.
Advantages
One advantage of silver soldering is the use of lower temperatures that are less costly. Soldering is also good when joining delicate materials. That’s because of the lower heat temperatures.
Disadvantages
Silver soldering is sometimes disadvantageous because it costs a lot. Most companies prefer silver soldering to copper brazing. Especially on carbide joints because of the strength needed.
Copper Braze or Silver Solder - What Should You Choose?
Whether you need to use copper brazing or silver solder is a decision that needs you to look at many factors. One major factor is the type of material you’re joining and the cost of the joining method. You can get permanent bonds using adhesive bonding and soldering. Brazed joints are stronger and more resistant to vibration and shock.
Tail-hole copper braze is suitable for those who are looking for a cost-effective way to make joints.
Silver soldering is a good choice when working towards making a flexible joint. Besides looking at the strength of the filler metal for a joint, there are other things to factor in. The overall assembly and strength of the joint after the joining process matter a lot.
It gives a good idea to make a choice between soldered and brazed joints for your needs.
Silver soldering is a good choice when working towards making a flexible joint. Besides looking at the strength of the filler metal for a joint, there are other things to factor in. The overall assembly and strength of the joint after the joining process matter a lot. It gives a good idea to make a choice between soldered and brazed joints for your needs.
What Is Our Approach?
By now, you know the notable differences between tail-hole copper braze and flat-bottomed silver solder. So, you might be wondering what FitCarbide’s approach to both these methods is.
Well, we prefer the flat-bottomed silver solder method, no matter how costly it may get. The cost of silver is 4000 RMB/kg to this date.
But, instead of the cost, we should focus on the quality that this method brings in.
You can see it through this image.
In most cases, many suppliers use the tail-hole copper braze method. In this method, the chances of concentricity error between the alloy and steel handle are high. As a result, the operator may feel difficulty controlling the steel shank. Sometimes, it may also bend the handle.
See this image to spot the difference.
Thus, it is preferable to use the flat-bottomed silver solder method. It will guarantee the toughness and strength of the alloy. So, whenever you search for a carbide burr manufacturer, make sure you settle on FitCarbide.
Final Thoughts!
The mechanical properties of carbides make them strong enough for complex applications. It makes them suitable for applications such as mining and cutting. These are some of the critical factors to consider when brazing carbide. Wettability of the filler metal is another crucial consideration when doing carbide joining. That’s because you will need enough wetting to be able to produce a strong joint.
Our joints forming processes follow a flat bottomed silver solder method. Temperatures are generally between 820°C to 850°C degrees. The use of low heat ensures little to no damage to the products during the process.
After the process of welding, each product goes through testing for concentricity. It helps ensure the durability, hardness, and concentricity of the alloy. If you are looking for high-quality carbide burrs, please write us a note through our contact us section.