The extrusion process pushes metal through a pre-formed die to shape it into a carefully designed cross-sectional profile. This process can achieve intricate cross-sections while simultaneously creating a quality surface finish. Many find this process especially useful for weak or brittle metals, since extruding relies entirely on compression and shearing.
The extrusion process is available in two different types. Continuous extrusions, in theory, can go on forever, creating one endless piece of material. Semi-continuous extrusions, conversely, are created in sections and create multiple extruded pieces.
How Is Metal Extruded?
Extruding metals may also increase the strength of the material and can be done with either hot or cold material.
Heated billets of metal are hydraulically compressed into cylinders that contain dies. The dies allow the pressurized billet to escape via orifices of the desired shape. The metal emerges from these openings as a continuous bar with the same cross-sectional shape as the die opening. With the use of two sets of dies, stepped extrusions are created.
Lubricant reduces friction, protecting the die surfaces. Graphite is often used on non-ferrous alloys, and glass is the lubricant of choice for hot steel extrusion. The extrusion process can produce a wide array of configurations, including complex non-uniform and non-symmetrical shapes that would be difficult or impossible to roll. Metal extrusions can easily replace cumbersome or uneven seams created through other methods such as joining, welding, or riveting.
The extrusion of cold metal has gone by a variety of names, including:
- Impact extrusion
- Cold forging
- Cold extrusion forging
- Cold pressing
- Extrusion pressing
However, cold extrusion is likely the most common term in the steel sector. Impact extrusion is also a widely accepted term for the cold extrusion of non-ferrous metals.
The process usually involves a high-speed punch, which strikes a metal blank within a die cavity. The force of the punch drives the blank through space between the punch and die. The speed and distance of the punch can be controlled via various mechanical settings on the machine itself. The thickness of the final extruded part is will be determined by the distance setting.
Cold extrusion offers high strength, because of severe strain-hardening, good finish, stringent accuracy, and lower production costs due to less operational setup and requirements.
Which Metals Are Used for Custom Extrusions?
Almost any metals can be extruded, though doing so can be cost-prohibitive for high strength alloys. Below is a list of the most common metals used independently, or as alloys, as well as examples of their common end uses.
Manufacturers can extrude aluminum—the most frequently extruded material—using either the hot or cold methods. Extruded aluminum can be fabricated, painted, and anodized, and it produces complex cross-sections with aesthetically pleasing surface finishes. Because of its high corrosion resistance and excellent thermal conductivity, extruded-aluminum products play large roles in the construction, automotive, aerospace, industrial, and domestic product manufacturing sectors. Because of its light weight and affordability, aluminum is the metal of choice for extrusion projects that seek to optimize strength without sacrificing the end product’s weight.
Brass extrusions create end products that resist corrosion, benefiting applications that require optimal performance for long periods in various weather or atmospheric conditions. Brass-extruded products are known for their durability and aesthetic appeal, providing a golden glaze on handrails, doors, columns, furniture, gates, and other ornamental materials. Brass products also form major parts of automotive components, pipe connectors, and industrial machinery.
Like aluminum, titanium provides a similar level of strength compared to heavier metals like steel, but its density is lighter, allowing manufacturers to reduce the amount their end products weigh. Aerospace manufacturers especially value titanium for its heat-resistant properties, keeping its shape at temperatures exceeding 800°C. Extruded titanium also undergoes a number of finishing processes such as heat treatment to refine grain structure and chemical treatment to enhance machinability.
Nickel extrusion creates high-strength products that are silver-gray in appearance. Despite nickel’s toughness, extruded-nickel products retain a degree of malleability that allow them to perform well in a variety of applications. Because nickel can withstand direct impacts without weighing too much, it’s ideal for door and window fasteners, locks, mining equipment, musical instruments, animal harnesses, electronic components, and industrial machinery. Nickel also can be alloyed with metals including silver, copper, and zinc, creating a variety of color customization options and allowing it to be used for a range of architectural purposes.
Metal extrusion also works well with copper, zirconium, and beryllium. Electronics manufacturers in particular rely on extruded copper to create wire, and it also forms essential parts of electrodes for welding, pipes, bars, and tubes. Zirconium benefits a wide range of forming and mechanical applications, and beryllium appears in many military and commercial guidance systems as well as the structural components of satellites and spacecraft, alloying well with copper.
Lynch Metals Offers Custom Aluminum Extrusions
Strong, durable, and light, extruded aluminum offers design flexibility as a corrosion-resistance choice for a wide variety of needs. Aluminum’s physical characteristics of malleability and ductility allow it to be easily extruded. At one third the density and stiffness of steel, extruded aluminum provides for both strength and stability at an efficient production cost. Coming with a low recyclability cost, aluminum has a very high rate of scrap recovery, making it a highly economical and environmentally sustainable material.
At Lynch Metals, we specialize in working with our customers to develop cost-effective engineered material solutions, such as extruded aluminum. Feel free to contact us with your questions regarding aluminum extrusion sourcing and distribution to see how Lynch Metals can positively impact your bottom line.
About Lynch Metals
Since opening in 1991, Lynch Metals has a premier North American supplier of aluminum fin stock and brazing sheet. While our initial focus was on aerospace, today we have expanded into other sectors, including automotive, signage, and telecommunications. We offer a range of in-house metal processing services for our customers, including:
- Slitting and Rewinding
We are the only distributor to operate a Kampf high-speed slitter, which runs at 1600 feet per minute. In addition we also have Chicago Slitter, Goebel, and Rusch slitters in house, and we have three Rowe cut-to-length processing lines. We can custom cut widths between 10 ft. and 60 ft. Rewinding inner core widths vary in size, according to each machine’s capability.
- Precision Saw Cutting
Our MetlSaw precision saw cutting machines produce burr-free edges, eliminating the need for smoothing and other secondary processes after cutting. These high-speed saws cut through both ferrous and non-ferrous materials, and are adept at achieving high production volumes. Our MetlSaw can cut a maximum of length of 192”, a maximum width of 24”, and a maximum thickness of 8”.
Many industries find customized blanks to be an economical alternative to stock sheet sizes. The signage sector also relies on blanks to manufacture products. Our advanced technology enables precise length tolerances of 0.01”. Cut-to-order blanks reduce waste, granting economies of scale and reduced costs.
Aluminum Alloys for the Aerospace Sector
The aerospace industry often chooses aluminum due to its strength-to-weight ratio and its inherent resistance to corrosion. Demand for aluminum in this sector is expected to double by 2028. As a distributor for several mills, Lynch Metals is poised to keep up with the increasing demand for aluminum parts and components. We can supply the fin stock and brazing sheets you need, when you need them.
Our proprietary Multiclad brazing sheet is well-suited for use by the aerospace sector. This unique brazing sheet consists of three layers instead of two, containing a 3003 interlayer between the 4000 Series cladding and the 6000 core. The result is a thinner, stronger sheet suitable for the stresses and harsh environments posed by aerospace applications.
Brazing Sheet for the Automotive Industry
Aluminum offers ideal properties for the automotive industry, including its crashworthiness—it absorbs shock twice as well as steel. Due to an increased focus on fuel efficiency and reducing emissions, lightweight aluminum is being used more in vehicle production.
Shortages of materials affect the entire supply chain, and this can be crippling in automotive. We source our brazing sheets from large, global producers, ensuring. stock is always available when you need it.
For easy identification, we can also mark the clad side of the brazing sheet with either a stencil or vinyl coating. These markings help to eliminate errors during production, ultimately reducing waste and reducing costs.
Channel Letter Coil and Aluminum Blanks for Storefront Signage
For storefront signage, we provide both channel letter coil and flat sheet stock. Our channel letter coil is used to manufacture three-dimensional lettering. We have more than 30 colors of aluminum for signage in stock to match your storefront or business aesthetic. Aluminum’s lighter weight and flexibility allow for creativity in your sign design.
Our customized blanking line enables us to produce signage with a variety of corner radii and holes. Aluminum signage withstands the day-to-day effects of outdoor conditions – up to and including severe weather – ensuring your sign will look professional for a long time to come.
4000 Series Aluminum Alloys for Telecommunications
The 4000 series aluminum alloy is created via a combination of aluminum and silicon. Due to its fluidity, this alloy is suitable for welding applications in the telecommunications industry. We can also use the 4000 series as brazing filler materials.
Lynch Metals: Your Premier Metal Supplier
Our extensive inventory expands beyond aluminum, and also includes stainless steel and nickel alloys. With our custom stocking program and Just-in-Time deliveries, you can free up valuable floor space while eliminating the hassle of excessive inventory. To speak with a salesperson, receive a quote, or have a catalog sent to you, please contact us.
At Lynch Metals, we continuously seek out the best machining tools and precision cutting equipment to support our operations. That is why we went to Chicago Slitter when we sought a machine to improve our coil slitting capabilities.
Chicago Slitter combines creative engineering and advanced technology to produce some of the most comprehensive coil processing solutions on the market. With more than 40 years in the business and a dedication to providing innovative production systems, we knew that Chicago Slitter would deliver a coil slitting machine that provided increased efficiency and maximum productivity.
What Can the Chicago Slitter Do?
Chicago Slitter coil slitting lines can tackle jobs ranging from simple to complex. The slitter features roll-only tension, wherein the metal is able to wind coils tightly without any risk of scratching the metal. Roll-only tension accomplishes this by eliminating surface-to-surface contact.
Coil slitting lines from Chicago Slitter feature higher yields, high versatility, and increased safety. This machine enables work with metals of different thickness levels and myriad surface conditions.
Chicago Slitter’s coil slitting lines also include other benefits, such as:
- Smart control systems for improved repeatability
- Faster production speeds
- Quicker recoiler drum and tooling changeovers
- Push button tooling lock-up
- Reduced labor costs
Capabilities at Lynch Metals
At Lynch Metals, we have an extensive quality management program that is both ISO 9001: 2015 and AS9100C certified, ensuring that you will get the best quality services, materials, and customer support that the industry has to offer.
Our new Chicago Slitter coil slitting line gives us improved capabilities, such as:
- Can take in coils up to 30,000 pounds
- Coil thicknesses between 0.015” and 0.250”
- 1,200 ft./min
- Outside coil diameter of 60”
- Inside coil diameters of 16″, 20″, or 24″
Our experienced team understands that slitting and rewinding aluminum and stainless steel can be a costly and timely process if not done with 100% accuracy and competence. That is why we only use advanced machines and extensively train our operators on their use.
With our high-performance coil slitting line, we are able to mass produce coils from 1-inch to 60-inches wide, and up to 18,000 pounds. The accuracy offered by our Chicago Slitter machine and the expertise of our staff mean that the end quality of these coils makes them ideal for high-performance applications in the automotive and aerospace sectors.
At Lynch Metals, we have a wide range of slitters, including the Kamph high-speed slitter, two industrial Ruesch slitters, three innovative Goebel slitters, and our Chicago Slitter. This range of equipment means we are not only able to give our customers the very best in accuracy and precision, but also an affordable solution to their mass production coil-slitting needs.
Aside from our high-quality coil slitting lines, we support all of our products with superior customer service. Our team will take the time to answer any questions or concerns that you may have about any of our services. If you would like to talk to someone about our coil slitting services, or any other aspect of our metal processing programs, please contact us today.
Industries across the manufacturing spectrum prize aluminum for its lightweight, yet durable properties and its excellent abilities to conduct thermal and electrical energy.
Aluminum 4047 is one of the most popular types of aluminum alloy. Often compared with aluminum 4043, it’s a non–heat-treated alloy primarily composed of silicon, iron, copper, zinc, magnesium, and aluminum.
Aluminum 4047’s higher silicon content minimizes its shrinkage and gives it a smooth finish, setting it apart from aluminum 4043. Furthermore, it can withstand higher temperatures than other aluminum alloys, meaning that it performs better in automotive and aerospace applications.
What are the Advantages of Working with 4047 Aluminum?
Aluminum 4047 comes with many advantages, including:
- It’s comprised of 12% silicon, compared with aluminum 4043’s 6% silicon content. This improves its fluidity during welding, especially for heat exchanger fabrication welders. The higher silicon content also reduces weld leakage, creating a smooth and aesthetically pleasing finish.
- It has a higher melting point. Aluminum 4047 liquidates at higher temperatures than aluminum 4043, meaning that aluminum 4047 resists cracks better and is smoother to the touch.
- It resists corrosion. Thanks to aluminum 4047’s 12% silicon content, it resists corrosion and wear better than aluminum 4043 and other alloys. Its strength is one of the main reasons why aluminum 4047 can bond and protect other metals so well.
Applications of Aluminum 4047
Aluminum 4047 works well as a cladding alloy or filler material.
Cladding protects less wear-resistant metals by coating them with a protective metal. Aluminum 4047’s strength renders it an excellent cladding material without drastically increasing the cladded product’s weight.
Aluminum 4047 can be found in a number of vehicle parts due to its ability to handle adverse environmental conditions without increasing the vehicle’s weight. It also appears in engine blocks, especially crankcases. Cars constructed of aluminum alloys often employ space frames made of extruded profiles to guarantee rigidity.
Aluminum–magnesium alloys have formed essential parts of aerospace projects since the adoption of metal-skinned aircraft. Aluminum 4047 resists heat much better than other alloys when combined with magnesium, reducing the flammability of finished projects. The aerospace industry also avoids stress and heat-related wear by joining parts using aluminum 4047 fasteners.
You can find aluminum 4047 practically everywhere. It appears in window frames, leak-tight joints, welding filler wires, and housing. The alloy also clads microwave-integrated circuits with laser-welded covers. Any type of construction that requires a lightweight yet durable material stands to benefit from the use of aluminum 4047 alloys.
Work With Lynch Metals for Your Next Aluminum Project
Founded in 1985, Lynch Metals is a premier supplier of aluminum brazing sheets throughout North America. We credit our success to our team of welding experts, knowledgeable sales representatives, extensive inventory, and specialized processing equipment. We’re also one of the largest distributors of both painted and anodized sheet in North America.
To learn more about our aluminum offerings as well as our line of steel products, contact us today.