Aluminum a Preferred Metal in Aerospace

Why is Aluminum A Preferred Metal Choice in Aerospace Industry?

According to the Aluminum Association, the history of air and space flight parallels the history of aluminum alloy advancement and production. Next to steel, aluminum sheet is the most commonly used and commercially available metal. Its soft, ductile texture has been fortified with a number of different metals to create alloys that exhibit highly useful qualities that have served the aerospace industry for over 100 years.

First Flight

Aluminum’s lightweight and high strength-to-weight ratio make it a good choice for aircraft, which is probably why the Wright brothers chose it to build parts of the engine used for their ground-breaking successful flight back in 1903.

Though the first primitive airplanes were made of lightweight wood, the downside of wood is that it’s susceptible to rot. For that reason – and as it became more readily available – aluminum became the go-to construction material for aircraft by the beginning of WWI.

Rise of the Aluminum Industry

A generation later during WWII, the U.S. built almost 300,000 aircraft, both for itself and our allies – with the help of a flourishing aluminum industry.

After the war, the beginning of spaceflight was achieved with the help of aluminum. For instance, the Titan family of rockets used to launch the manned Gemini craft into orbit in the 1960s was made of aluminum.

In use from the 1960s to the 1990s, the Lockheed SR-71 Blackbird reconnaissance plane – one of the fastest aircraft ever built – had an internal aluminum frame

From 1969 to 2003, aluminum-skinned supersonic Concorde passenger jets flew across the Atlantic at twice the speed of sound.

The Space Shuttle Discovery, which flew astronauts around the Earth from 1984-2011, had a backbone of aluminum alloy plate and had an external fuel tank made of aluminum. Its solid booster rockets were powered by aluminum metal mixed with solid ammonium perchlorate.

Modern Age of Aluminum

Still one of the world’s most popular jet planes, the Boeing 737 is approximately 80 percent aluminum, with different alloys used for different parts of the aircraft. For example, the fuselage skin, slats, and flaps are made of Aluminum 2024 (alloy of aluminum and copper), chosen for its good fatigue performance, fracture toughness, and slow crack propagation rate. Meanwhile, the wing upper skin, spars & beams are made of Aluminum 7075 (aluminum alloyed with zinc, magnesium, and copper), known for its high compressive strength-to-weight ratio.

The primary structure of NASA’s Orion spacecraft, the next-generation space exploration vehicle which will someday transport people to Mars, is constructed of an aluminum-lithium alloy.

Aluminum: The Cost-Effective Solution

Though not as strong as titanium or carbon-alloy steel, and heavier than composites, aluminum costs less and has a good balance of strength and low weight that make it a great fit for aircraft. When alloyed with other materials, aluminum exhibits many additional properties beneficial to flight, such as stress corrosion cracking resistance and high tensile strength.

Aluminum sheet & plate is as strong as steel at a fraction of the weight. Aluminum sheet & plate is also highly resistant to corrosion, which adds to its overall value. As manufacturing technologies advance, aluminum is sure to stay in the forefront of air and space craft for the foreseeable future.

For more information about aluminum metal supplies, contact Industrial Metal Supply today.


7 Suprprising Things Made of Brass

7 Surprising Things Made of Brass

Brass – an alloy of copper and zinc – is one of the most widely used alloys. Known for its decorative attributes and bright gold appearance, brass also exhibits durability, corrosion resistance, and high electrical conductivity.

Brass sheet and brass plate are more malleable than bronze, and generally very easy to cut, machine, and fabricate, making it useful in the manufacturing, construction, electrical and plumbing industries.

Accidential Discovery of Brass

As far as we know, brass was discovered accidentally, when metalworkers in ancient Asia smelted a crude form of brass from zinc-rich copper ores. Then about 2,000 years ago, the Greeks and Romans began melting calamine ore, which contained copper and zinc – causing zinc ions to be dispersed throughout the copper.

Over the centuries, a number of other processes have been developed for making brass, with additional metals, such as aluminum, lead, and arsenic, added to create alloys with different properties.

Brass’ Growing Uses

Because of its wide versatility, brass has found its way into a surprising range of applications, including:

Ammunition casings – Spark resistant, low-friction, corrosion-resistant, and non-magnetic, brass can be easily rolled into thin sheets and formed into cartridge shells. It is also easy to recycle for ammo reloading.

Marine hardware – Due to its hardness, toughness, and corrosion resistance – even in the presence of salt water – brass was used for centuries as sheathing on the hulls of wooden naval ships, for navigational tools, and later, marine engines and pumps.

Electronic components – For electrical panel board switches and relays, as well as PCB plug pins, sockets and terminal blocks, the malleable, non-magnetic nature of brass, and the fact that it costs less than gold and silver, makes it an excellent choice of material.

Radiator cores, tubes and tanks – Brazed copper-brass radiators for cars and trucks cost less than aluminum radiators, are easier to manufacture, last longer, and are much easier to recycle, which makes them more energy efficient. They have also been shown to have a lower air-side pressure drop than aluminum radiators.

Musical instruments – The durability, workability, corrosion resistance, and acoustic properties of brass make it an excellent, economic choice for a wide range of musical instruments, from trumpets, tubas, and trombones to cymbals, gongs, and bells.

RV water pressure regulator and elbow fittings – Much stronger and tougher than plastic, brass fittings can stand up to high water pressure and reduce it to a manageable level for use in RVs.

Technical instruments – For centuries, non-magnetic brass has been used to make measuring instruments, such as compasses, astrolabes, barometers, chronometers, clocks, and watches. While retaining its hardness and strength, brass is easily worked and engraved with permanent indicator marks for reading the time, tide, direction, or barometric pressure.

Brass in All Shapes & Sizes

Brass can typically be purchased in a number of forms, including:

  • Round, square, rectangle and hex bar
  • Sheet and plate
  • Tubing
  • Angle and channel
  • Shim
  • Threaded rod
  • Foil
  • Decorative railing & accessories

Industrial Metal Supply stocks brass sheet and plate in many forms and in full sizes or pre-cuts, as well as a line of decorative brass railing from Lavi Industries. Questions? Contact us today!


Use + Benefits of Diamond Plate (aka Tread Plate or Floor Plate)

The three names, “tread plate,” “diamond plate,” and “floor plate,” can be confusing, but essentially they are all metal sheet or plate products, though they may have originated in different industries and applications. Each term refers to metal sheet or plate with a raised pattern on one side, and typically used as a slip-resistant surface or decorative siding.

The pattern on a tread plate may be alternating diamond or lozenge shapes or small individual blocks of raised bars in a checkerboard arrangement.

Rolled aluminum diamond plate comes in alloys including 3003 and 6061 (conforming to ASTM B632). Steel tread plate (steel tread plate is also called floor pate, aluminum is not) conforming to ASTM A786 comes in carbon, low-alloy, high-strength low-alloy, and alloy steel hot-rolled diamond plate.

Tread plate is available in a variety of thicknesses and load capacities, and it can be welded and cold worked.

Benefits of Tread Plate

The benefits of this versatile material are numerous, including:

Slip resistant – Raised pattern provides traction on steps, ramps, ladders, floors, tailgates, running boards, catwalks, loading docks, etc., even when wet, icy, or covered with snow, chemicals, or mud. Embossed firetruck quality (FTQ) tread plate meets NFPA industry safety regulations for slip resistance.

Corrosion resistant – Tread plate made of corrosion resistant metals, including stainless steel and aluminum alloys, provides years of service even under the toughest conditions, including marine locations.

Hygenic – Tread plate is easy to wash down and is able to resist damage from strong, corrosive cleaning agents. This makes it ideal for areas where frequent sanitizing is required, like food processing plants, kitchens, restaurants, ambulances, livestock transport, and more.

Protective – Tread plate prevents damage to walls, doors, corners, dollies, skids, etc. It also protects bumpers, treads, truck beds, tailgates, and bodies of commercial, off road, and other vehicles.

Attractive – Various raised patterns, materials and finishes are available for use in architecture, furniture making, etc. Firetrucks and shop walls are two places tread plate is commonly seen.

Applications of Tread Plate

The benefits of steel or aluminum tread plate make it ideal for a multitude of applications. Tread plate can be found in parking lots, garages, stairways, step ladders, elevators, loading docks, warehouses, distribution centers, hospitals, factories, ships, floating docks, refrigerator trucks, walk-in freezers, elevators, walkways, handicapped access ramps, truck tool boxes, trailers, and much more.


Which Metals Can Be Welded and Why?

Weldability is everything. Metals with a high weldability are easier to weld and retain a higher weld quality than other metals, so it’s important to study these factors before choosing materials for a project.

Once you’ve narrowed down your selection to a few metals, the next step is to determine which welding process you’d like to use. Some methods require more skill than others, such as TIG welding — and these will affect which metals are at your disposal. For example, the ideal metals for MIG welding are carbon steel, stainless steel, and aluminum, all for different reasons.

The main parameters that determine a metal’s weldability include the electrode material, cooling rate, shielding gases, and welding speed. Every metal is unique. To a certain extent, all metals can be welded, but there are clear advantages and disadvantages to each.

Stick welding, also known as shielded metal arc welding (SMAW), is one of the most common welding methods out there. To get started, you’ll need a welding machine, a proper electrode (we recommend DCEP for DC welding), a safety helmet, clamps to hold the joints together, and your welding metal of choice. With this method, you are melting a metal rod with a special flux coating that prevents oxygen contamination — hence the “shielded metal” name. Stick welding can be used to weld steel, iron, aluminum, copper, and nickel.

Unlike stick welding, gas metal arc welding (or GMAW) does not have a coating over the electrode rod. Instead, the welding gun disperses a shielding gas that protects against contaminants. It’s the most common industrial welding process today, and can be used for steel, cast iron, magnesium, and many other metals.

Ultimately, there is no clear-cut answer when deciding which metals and welding methods to use. It’s best to figure out which metals are best suited (and most cost-effective) for your project, and then decide on a welding style that can be performed with your skill set.


Types of Welding

Arc welding has a number of distinct styles, each with its own approach to binding multiple metals together via a metal electrode. Below, we’ve showcased four of the most popular welding methods, with their unique advantages and disadvantages.

MIG

Invented in the 1940s for welding non-ferrous materials, MIG used to stand for “metal inert gas”, because the welding gun would disperse an inert gas to prevent atmosphere contamination. Today, the process has incorporated carbon dioxide instead of inert gas, so it is officially known as gas metal arc welding (or GMAW). Many people still call it MIG, however. MIG welders can use globular, short-circuiting, spray, and pulse-spray methods to create an electric arc between their electrode wire and multiple metal joints. It’s the most common industrial welding process today, though it is not recommended for outdoor use (due to unpredictable air).

TIG

Tungsten inert gas (TIG) welding is a more difficult process to master, but it gives the user more power and control over the final weld. Instead of wielding a metal alloy electrode, this method uses a non-consumable tungsten version with an inert shielding gas. Depending on the weld being performed, a filler metal may also be used. TIG requires serious coordination with both hands, so it’s not recommended for beginner welders.

Flux

Next, flux-cored arc welding (FCAW) harnesses a continuously fed electrode tube with a cleaning agent (called a flux) and a constant power supply. Typically, the flux provides enough protection from atmospheric contamination, but sometimes an additional shielding gas is used. The main advantage over other arc welding methods is the elimination of stick electrodes, which makes welding faster and more portable.

Stick

Finally, shielded metal arc welding (SMAW, or stick) is an extremely popular method for construction and repairs. Coated with a flux, an electrode rod is melted to form an electric arc between multiple metal pieces. As the electrode is used, the flux changes into shielding vapor and slag, both of which serve as protection against contaminants. Stick welding requires less equipment than many other welding methods, and is excellent for stainless steel and iron.


The Science of Corrugated Metal

Corrugated metal provides a lightweight, portable, low-cost and durable architectural material that can withstand hail and windstorms while resisting corrosion for years. Corrugated steel can be painted or coated and is a popular choice for decking, roofing, and siding in commercial, agricultural and even residential buildings.

Corrugated metal starts with carbon steel sheet which is then pressed into three-dimensional patterns, called corrugations, using a series of rollers in a cold roll forming process. Different roller die arrangements produce different types of corrugation, including waves, squares and angles. Cold rolling allows a thicker and stronger product that also presents a better appearance than hot-formed steel. Finished sheet is then sheared off to the desired length.

For artistic effect, corrugated steel sheet may formed with uncoated steel or corten steel, a weathering steel that gives a rusted look right off the shelf! But most building applications require protection from the environment. There are different ways to achieve this, depending on cost and application, e.g., galvanization, painting or coating.

According to the American Galvanizers Association, galvanization is a method of protecting steel from corrosion by dipping it in a vat of molten zinc. The iron in the steel reacts with the zinc, forming a tightly bonded alloy coating that provides a shiny finish. As the galvanized finish ages, it will grow a white oxide coating which protects the metal from further corrosion, even at scratches or the sheared edges on galvanized corrugated sheet.

In addition to applying the zinc in this hot-dip batch process, galvanization can also be accomplished with continuous sheet galvanizing. During this process, rolls of sheet steel are passed through an annealing furnace to clean and prepare the surface, then rolled through a zinc bath, pulled up vertically and allowed to dry. This type of galvanized coating is thinner and less protective, and so should be used indoors only.

An alternate version of galvanization is the patented Galvalume process. First discovered by Bethlehem Steel in 1972, Galvalume steel coating contains about 55 percent aluminum and 45 percent zinc, along with a tiny percentage of silicon. The silicon helps the coating adhere to the steel, even during the corrugation process.

The aluminum in Galvalume provides corrosion resistance against atmospheric conditions. When the coating is applied, microscopic areas of aluminum and zinc form. The aluminum areas provide a barrier of protection from corrosion while the zinc areas provide galvanization. In most applications, Galvalume provides greater protection than galvanization, but there are exceptions, such as in the alkaline environments of concrete and mortar, or in agricultural or animal confinement areas.

For more information or to order, contact Industrial Metal Supply.


Chromoly vs. DOM Tubing

Steel tubing has many uses, ranging from bicycle frames to roll cages to rifle barrels. Two of the most commonly specified types are chromoloy tubing and DOM tubing.

Most steel tubing is made by cutting rolled steel into thin strips that are cold formed length-wise into a tube shape which is then welded together. Further processing creates the desired mechanical properties, dimensions, and finish. Seamless tubing is also available.

Chromoly tubing

Chromoloy tubing is made from a family of low-alloy steels that contain chromium and molybdenum (SAE 4130 or 4140), along with the iron, carbon and other elements. The chromium adds strength, hardenability and a level of corrosion resistance to mild carbon steel, though Chromoly is not as corrosion resistant as stainless steel.

Chromoloy is heavier than aluminum alloys, but its high strength-to-weight ratio makes it desirable for aerospace components and race car parts. It is also used in automotive gears and crankshafts, gas delivery tubing, and machine shafts.

ERW

Electric resistance welding (ERW) is a type of welding process that uses the heat generated by passing a high-frequency electrical current through the metal, along with pressure to hold the parts to be welded together for a specific length of time. ERW can be used for spot welding and also for welding tube seams.

DOM Tubing

Drawn-over-mandrel (DOM) tubing is not made from any specific alloy – it can be used with mild steel, chromoly or another alloy, such as SAE 1020 or 1026 steel.

DOM tubing is often incorrectly referred to as “seamless tubing” because the seam is almost invisible. DOM is a process that takes the rough cold-formed steel tube and continues to process it further to smooth out the internal surface of the weld seam while improving its mechanical characteristics. This is accomplished by annealing (heating) the tube to soften it so that it can be pulled over a tapered steel shaft (i.e. “drawing the tube over the mandrel).

The mandrel is a little thicker than the inner diameter of the tube, and as it moves through the length of the tube, it smooths the inner surface while stretching it wider. The tube is also drawn through dies that shape and size the outer surface. The combination of mandrel and dies achieves the required wall thickness, inner and outer diameters.

The DOM process creates a more concentric, uniform product with dimensions more closely toleranced to a customer’s exact specifications. DOM tubes also have superior mechanical properties, including increased hardness and tensile strength and a sound welding seam. This makes them ideal for use in mechanical parts, such a hydraulic cylinders and automotive components, without requiring further machining.

Seamless Tube

True seamless tubing is made from a heated cylindrical steel billet (or blank) which is hollowed out with a rotary piercing process. The solid billet is rolled between two rollers toward a tapered mandrel pointing at the end of the billet. Forces from the rollers create an opening at the center of the billet’s cross section. The opening grows, forming a tube as the billet continues to travel over the mandrel and through the rollers. Once this rough tube cools, it is further processed to achieve the desired thickness, diameter and finish with either a cold or hot forming method.

Cold drawn steel (CDS) is 1018/1026 steel tubing with uniform microstructure, tight tolerances, high strength-to-weight ratio, high tensile strength, thinner tube walls, and a superior surface finish compared with HSF tubing of the same steel grade. It generally requires no additional machining and is used in race cars, truck and auto parts, and hydraulic cylinders.

Hot finish seamless (HFS) tubing is less costly than CDS tubing and can be easily machined to exact specifications. It is used for rollers, sleeves and hydraulic cylinders.

 

References:

https://steeltubeinstitute.org/drawn-over-mandrel/

 


Which Metals Are Magnetic?

Discovered by ancient civilizations around 500 BC, magnets have become an essential component in modern technology. Demand for magnets continues to grow as smartphones and other electronic products become ubiquitous. But which metals can engineers use to create a magnetic force? There are four main magnet types:

Diamagnetic

To start, diamagnetic metals are weakly repelled by permanent magnets. Typically made from nickel or iron, permanent magnets retain magnetism after being influenced by an external magnetic field. On the other hand, diamagnetic metals include copper, lead, and graphite. Although they make a weak contribution to magnetic fields — since they barely react with permanent magnets — they are magnetic metals nonetheless. To a certain extent, all materials experience some form of diamagnetism, including trees and clothing.

Superconducting

Next, superconducting metals create a strong repulsion in permanent magnets. These include gallium and tin. All superconductors need to be at an extremely cold temperature (known as the “critical temperature”) for magnetic repulsion to take place. Once the superconductor metal breaches this temperature, it reaches a point where there is zero electrical resistance. Other metals may be conductors, but their impurities prevent them from reaching zero resistance.

Paramagnetic

On the opposite end of polarization, paramagnetic metals are weakly attracted to permanent magnets. Most chemical elements display some degree of paramagnetism, which means they have a positive susceptibility to magnetic fields. However, if there is no external magnetic field influencing them, paramagnets will not have any magnetization. Paramagnetic metals include gold and aluminum.

Ferromagnetic

Finally, ferromagnetic metals have a strong attraction to permanent magnets. When we observe magnetic attraction or repulsion in daily life, we are seeing ferromagnetic materials in action. Only a few metals are ferromagnetic, however, and these include iron, cobalt, nickel, and some rare earth metal alloys. These materials form the basis of many electric products today, such electric motors, hard disks, generators, and much more. Most permanent magnets are ferromagnetic.


How to Rust Metal

It’s understandable that most people want to prevent their cars and power tools from rusting, but some steel objects actually gain character from having a nice rusty patina. With a few household chemicals, it’s easy to speed the oxidation process along. Below, we’ve shared the basic steps to give your outdoor decorations a charming, weathered look.

  1. Buy Materials: You might already have some of these products in your pantry, so scan through the house before buying anything. To give your steel that rusty finish, you’ll need table salt, white vinegar, and degreaser, along with measuring cups/spoons and a spray bottle. We also recommend you buy a new bottle of hydrogen peroxide, instead of using an old one in your medicine cabinet. For safety purposes, you should be wearing goggles and chemical resistant gloves at all times. Remember, you’re going to be combining harmful chemicals, so be careful!
  1. Degrease the Steel: After stripping your steel of any coating or paint, the metal will be ready for degreasing. Read the degreaser bottle’s instructions as you apply it to the metal, and take care not to touch it with your bare hands. You want the degreaser to work its magic, but you don’t want to add more oil and dirt in the process.
  1. Pickle the Steel: Yes, the next step is just like pickling cucumbers, only here you’re pickling steel. This helps to create a uniform coat of rust, instead of certain areas being rustier than others. Pour some white vinegar into the spray bottle and then spray every inch of the metal object. Let it dry in the sun, and then repeat several more times. Now, your steel will be ready for the main event.
  1. Make It Rusty: So you’ve prepped the metal object for rusting, but how does the oxidation process actually happen? First, you’ll need to create a rusting solution by combining 16oz hydrogen peroxide, 2oz white vinegar, and ½ tablespoon of salt. If possible, mix this solution in the spray bottle with some of the leftover white vinegar. Shake it up so that everything mixes well, and then start spraying down your object. If the rusting doesn’t start happening immediately, you may need to put your object in direct sunlight for a while. Heat helps the process.

After you spray the metal, let it dry, and then repeat for about 7 cycles, your steel should look like it’s aged years. Make sure you don’t touch the rust until it has fully dried out, because it might rub off. The longer it stays in the sun, the better.


How to Stop Rust

Rust on any object — whether it’s a car, power tool, or a bridge — is an unattractive and often dangerous phenomenon that should be prevented whenever possible. Typically, rust occurs when metal is exposed to water and oxygen for a prolonged period of time. Iron and oxygen combine to form iron oxide, whose properties create the flaky orange-yellow coating that we all know as rust. The initial corrosion is fairly easy to remove, but wait too long, and you’ll have a car destined for the junkyard. Below, we’ve outlined five approaches to defeating rust before it spreads.

  1. Bluing: By dipping metal objects into a solution of water, sodium hydroxide, and potassium nitrate, you give them a strong corrosion resistance. This technique is often used with guns and clocks, and the name refers to the metal’s bluish finish when immersed in the solution.
  1. Clean Your Car Regularly: It may go without saying, but washing and waxing your car is extremely important for rust prevention. Dirt can also accumulate underneath your car over time, retaining moisture, so it’s smart to spray the undercarriage often as well. Although new cars are coated with the latest chemicals to fight against rust, vintage vehicles require an attentive eye to ensure that they remain drivable.
  1. Invest in Rust Prevention Products: These over-the-counter chemicals can be found in a variety of application styles — from aerosol sprays to cloth wipes. It all depends on the object you’re trying to protect. For small tools and outdoor gear, we recommend the Sentry Solutions TUF-CLOTH. For vehicles and larger metal parts, the Boeshield T-9 aerosol can was originally designed by Boeing Aviation for their aircraft components, so it does the job.
  1. Install a Dehumidifier: By controlling the exact amount of moisture in the air, you can slow down the oxidation process in your garage, basement, or any other sealed work space. If you own or work with valuable metal objects, it’s definitely worth the small initial investment.

5. Scrape Off Rust Immediately: Rust spreads like an infection, so it’s important to deal with oxidation as soon as it appears. To help slow down the process, you can scrape off loose rust pieces with a razor blade and then scrub the affected area with warm water and soap. Finally, apply a metal conditioner to prevent further rusting, and then put a new coat of paint on the area (if necessary).