Brazing is the process of joining ceramic to metal or metal to metal components using brazing material (metal alloy) and heat. During the process, the filler metal (or a nonferrous alloy) melts and flows into the joints of the metal pieces through capillary action. The joining process is similar to soldering. However, brazing requires high temperatures and requires more rigid filler metal.
The melting temperature of the filler metal is lower (generally between 450-600°C) than the adjacent substrates joined together (or the parent metal). Different heating methods used to join the materials include induction brazing, electric heating, torch brazing, or vacuum furnace brazing.
The brazing process is carried out in a flux or a purge chamber that provides an inert gas environment and prevents reactive metals, such as oxygen, from interfering with the process.
Brazing offer several advantages over welding processes, such as:
- Brazing does not require the melting of metal pieces to join them; rather, it melts filler metals, producing clean brazed joints. In contrast, welding by melting the workpiece metal results in a rough, unpolished joint.
- Brazing does not require additional steps or secondary finishing of materials. However, welding does.
- Brazing can be used to join multiple parts or complex items, which is challenging through welding processes.
Brazing has various applications in a range of fields, including aerospace, semiconductor, automotive, and defense industries. In this article, we will review in-depth about these applications, learn about the materials used in the process, and how Elcon Precision helps you with your brazing services requirements.
The Role of Brazing Services in Defense Applications
Brazing of metals has several advantages over other joining techniques, such as:
- Minimal oxidation
- Minimal part-to-part variation
- Competitive cost
- Robust bond
- Efficient turnaround
- Greater quality control
Because of these benefits, the technique is utilized in aerospace and defense to manufacture high-throughput strong parts with precision for a variety of applications. A few examples of applications that involve vacuum brazing services include:
- Hermetic feed-throughs
- Heat exchangers
- Electron gun components
- Window assemblies, viewports
- Vacuum electronics
And many more! Brazing services are an essential part of creating high-precision, reliable components in more than a few industries.
High-Quality Materials Used For Defense Brazing
Brazing can be used with most of the metals you know, and with the increasing number of alloys being developed, new services are also being introduced. Some of the metals and ceramics used for defense brazing include:
Ceramics have unique biochemical, thermal, and electrical properties that are exploited by aerospace and defense industries to design parts that are strong, durable, and run efficiently. Here are some examples of high-tech ceramic materials used in brazing applications:
- Aluminum nitride (AlN)
- Beryllia (beryllium oxide)
- Zirconia toughened alumina (ZTA)
The Brazing Process for Defense Products
Brazing is an effective technique to join two metal pieces with strength. The process involves the following step:
- Material selection: A suitable filler material is required that can create a strong bond between two substrates to be joined. Material is selected based on the client’s specifications of a brazed project.
- Material cleaning: Clean metal and/or ceramic surfaces are necessary for proper capillary action. Thus, remove any oil, dirt, or grease present on the metals. Different methods are used to clean different contaminants. For example, vapor degreasing is used to remove oil and grease, and metallic grit blast is used to remove dirt.
- Parts’ fluxing: Flux is applied to the metal surfaces before brazing to remove any oxides and allow the filler metal to smoothly join the surfaces.
- Assembling: Metal parts are assembled to achieve the required specifications before performing the brazing process.
- Heating and cooling: The assembled parts are subjected to heat, where the joining alloy melts and fills the gaps through capillary action. The step is followed by cooling the parts for strong and durable bonds.
- Cleaning and Inspection of the brazed joints: This step involved removing residual flux from the joints, using techniques like wetting or quenching. Then, the joints are examined for their performance and quality via testing such as helium leak testing, proof testing, pressure testing, and radiographic examination.
At Elcon. all these steps are carefully performed using high-through equipment and technology and high-quality chemicals.
Our team of experienced engineers understands your requirements, and based on material type and part geometry, they select appropriate brazing fixtures, joint designs, and processes to meet your needs.
For example, we join metal to metal or two dissimilar metals using atmosphere or vacuum brazing in a highly controlled environment to prevent oxidation of metal parts due to oxygen exposure.
Similarly, we use an active metal brazing process to assemble metal substrates to ceramic parts without metallization. The technique is also the most cost-effective approach to brazing the metals and does not require expensive tooling like conventional welding approaches. Based on your requirements, we can join metal components using laser, TIG, and spot welding approaches.
Why should you trust our process?
We follow all industry standards and have earned the necessary certifications that validate the quality and precision we put into our brazing processes. Our accreditations include:
- MIL-C-14550B (copper plating)
- MIL-G-45204 (gold plating)
- AMS-QQ-N-290 (nickel plating)
- QQ-S-365D (silver plating)
- NADCAP accreditations
Learn More About Brazing Services With Elcon Precision
Brazing is a process of joining two pieces of metals using filler materials, such as copper, Inconel, or nickel alloys. The technique is used to develop high-tolerance and high-strength parts and components for aerospace and defense applications.
If you’re looking for high-quality brazing services performed with precision, Elcon Precision has the solution.
We provide brazing and metal fabrication services for a variety of applications, ranging from high-tolerance aerospace and medical components to microwave-transmitting tubes and heat exchanger applications. With our brazed assembly services, you are guaranteed high hermiticity and repeatability, minimal oxidation, and minimal part-to-part variations.
In addition to high-volume and prototype manufacturing, we work with clean, low-vapor alloys, ensuring greater quality control and efficiency for our clients. Additionally, we offer military-approved gold, nickel, silver, and copper plating services.
At Elcon Precision, we only use qualified suppliers for material sourcing, and to entrust your confidence in what we do, we’ve earned all necessary accreditations required to prove the quality of our work, including ISO 9001:2015, AS9100D, and ITAR certifications.
The range of services offered by Elcon Precision includes:
- Proprietary metallization
- In-house metalizing, plating, and glazing
- In-house machining of fixtures
- Metal-to-metal brazing
- Partial pressure brazing
- TIG welding services
- Spot welding services
- Heat treating
- Turnkey manufacturing
- Leak testing
- Furnace brazing services
- CNC machining
- Photochemical etching
See a service that your business could benefit from? Request a quote today, and we’ll get back to you as quickly as possible to understand your needs.
If you have any questions, send them our way, and one of our team members will get back to you with the best possible answer.