Brazing, and Soldering

Key Differences Between Welding, Brazing, and Soldering

Welding, brazing, and soldering are methods that join two metal parts by melting a filler material. The fundamental differences between these techniques are determined by the temperature used and its effect on the base material. Each method is selected according to the type of material to be joined, the required strength, and the application’s needs.

What is Welding? Advantages and Limitations

Welding creates strong joints with higher tensile and stress resistance compared to brazing and soldering. This technique is often preferred for assembling large structures. In the welding process, intense heat is directly applied to the metal surfaces to be joined. This heat is high enough to melt the base metals and the filler material. Therefore, welding is performed at temperatures above the melting point of the base material.

However, welding has some limitations. In applications where aesthetics are crucial, it may not be preferred due to the irregular seams it produces. Additionally, the high processing temperature can cause thermal distortions and residual stresses in the joints. Welding is generally unsuitable for joining dissimilar metals.

Soldering: Ideal for Precise Connections

Soldering is performed at much lower temperatures than welding and brazing, typically below 449°C (840°F). This method is particularly preferred for more delicate joining requirements and is used for bonding thin metal parts.

Soldering is generally divided into two main types:

• Soldering
• Brazing

Brazing: Advanced Technology for High Strength

Brazing is a technique where metal parts are joined by forming a metallurgical bond using a filler metal. In this process, molten filler metal is drawn into the joint gap through capillary action, creating a strong and durable bond. Brazing is performed at temperatures ranging from 450°C to 1200°C.

Brazing Process in Controlled Atmosphere Furnaces

In our facility, critical components like vibration and discharge tubes used in refrigerator compressor motors are joined durably and with high performance in controlled atmosphere furnaces. Project-specific fixtures are used for brazing in controlled atmosphere furnaces. In some cases, fixtures are not needed, and parts are placed into the furnace at the correct angle and alignment for processing.

Strategic Advantages of Brazing

• Energy and Cost Efficiency: Brazing requires lower processing temperatures compared to welding, resulting in significant energy cost savings.
• High Efficiency: It ensures high repeatability and efficiency in industrial production lines, particularly in mass production applications.

Brazing is ideal for applications requiring joints with high heat resistance. It provides stronger bonds than soldering and creates long-lasting and durable connections while preserving the quality of metal surfaces. Brazing is commonly used in the following areas:

• Heating and cooling system pipes
• Automotive oil lines
• Joining steel, copper, and copper-coated (bundy) tubes

Considerations for Brazing

• Surface Cleanliness: The cleanliness of the materials to be joined directly affects the bond’s strength. Clean surfaces allow the molten filler metal to settle properly.
• Gap Adjustment and Material Selection: Properly adjusting the gap between parts and choosing the right filler material enhance joint durability.
• Protective Atmosphere: Using an appropriate atmosphere and temperature during the process prevents oxidation, improves process efficiency, and results in stronger joints.

Differences Between Welding, Brazing, and Soldering

Welding, brazing, and soldering are three essential manufacturing processes for joining metals and alloys. While all three methods share a common goal, their differences depend on the application areas and metalworking requirements. Welding melts metals at high temperatures, while brazing and soldering occur at lower temperatures. These differences significantly impact the advantages and limitations of each method. The choice of method depends on the desired bond strength, cost efficiency, and the properties of the workpiece.

Conclusion

Welding, brazing, and soldering are metal joining methods that operate at different temperature ranges and use distinct techniques. Each process offers specific advantages, and their differences play a critical role depending on the intended purpose, material type, and desired joint characteristics.

• Welding creates high-strength, permanent joints at high temperatures, making it ideal for automotive and industrial applications.
• Brazing occurs at lower temperatures and establishes strong bonds between metal surfaces, often used in pipes and pressure vessels.
• Soldering is suitable for more precise and delicate connections, typically performed at lower temperatures.

In summary, each joining method offers unique advantages tailored to specific operating conditions and requirements. For more information about brazing and our other joining solutions, feel free to contact us!