Use of tungsten past and present

Let's look at the use of tungsten circa 2007, as a theoretical four-person experience (a father, a mother and two children) has stood the test of time.

At home in the morning

On that day in 2007, my father woke up early (quietly disturbing his wife and children so as not to disturb them), his cell phone vibrating gently under the pillow.

The type of phone described in this article is long gone - replaced by the thinnest of smartphones. However, the mechanism by which a tiny tungsten portion is rotated by an electric micromotor inside the phone to generate vibrations is one of the uses of tungsten still in use today.

As my father stood on tiptoe in the house, he noticed the various lighting, including the soft glow of the bedside lamp, the use of a 15-watt incandescent bulb with tungsten wire and the bright halogen spotlight with high-performance tungsten wire in the bathroom.

The reality today is that incandescent bulbs with filament wires are on the decline, and even CFLS are rapidly succumbing to the efficiency of LED lighting. (Although wire wire is one of the tungsten uses that are good for our business, we are not one of the LED deniers!

Application of tungsten on road

Finally, in his car and on the way to the airport, my father turned on his window deicer, which used tungsten wires embedded in the front and rear windshields.

The app never really caught on with American-made cars, but it was widely used in Europe. In addition, metal cutting today provides tungsten filaments for this purpose in aerospace windshields.

The father points out that his 10-cylinder car engine runs very smoothly for a diesel. This is due to nearly 22 pounds (10 kilograms) of tungsten parts placed around the crankshaft to reduce vibration. This idea has gone the way of 10-cylinder diesel cars, favoring lighter, more fuel-efficient vehicles.

To barely avoid a collision on the highway, Dad quickly relied on his car horn -- an application that then, as now, required the flow of electricity and relied on switches made of pure tungsten, which in turn depended on expertise in how to cut tungsten.

Before dawn, a thin layer of tungsten bronze on the rearview mirror reduced the glare of the headlights behind him. This is also one of the uses of tungsten used today.

As the snow began to fall, the father thought of his brother-in-law in Finland, where hardmetal-encrusted tires were -- and still are -- useful in the cold winter weather because the local government allowed them. The hardness and wear resistance of the studs help prevent the car from slipping.

Of course, today's cars include more and more active safety technologies designed to improve safety and performance.

As he approached the airport, my father saw trucks with labels stating that they were equipped with modern emissions-reduction equipment. DeNOx catalyst, then and now used in many truck diesel engines, reduces nox concentrations in exhaust gases.

The catalysts are made of tungsten-containing ceramics, and the two materials work well together, given tungsten's ultra-high melting point.

In addition, the perfectly sized holes in the trucks' diesel injectors are made using Metal Cut's own tungsten electrodes. We ground the holes to a diameter tolerance of 0.5 micron to maximize full combustion and reduce particulate emissions.

Application of tungsten in air

Boarding the plane and finding his seat near one of the wings, father noticed the engine turbines. Turbine blades in the engine's high temperature zone were and are made of tungsten containing superalloys - another application that benefits from tungsten's high melting point.

As he took off, he looked out the window and noticed that the wing flaps and ailerons were working. In 2007 and today, tungsten heavy metal counterweights are part of the mechanism that controls the force applied to the flaps.

Ironically, while today we pay for all luggage and have to pay extra for excess baggage, the plane itself is full of heavy counterweights made of tungsten alloy. However, these are precisely designed for specific location and security purposes, so we don't complain.

Dad took out his laptop and iPod to pass the time and get ready for his business meeting. While these electronic devices have developed tremendously over the past decade or so, tungsten remains an integral part of their manufacture. Such as:

The printed circuit board inside the device is machined using a carbide router and a miniature drill bit.

Integrated circuit chips use tungsten conducting wires or plugs and tungsten silicide gate materials.

Tungsten and molybdenum alloys are used to produce equipment displays.

Probes made of tungsten or tungsten-rhenium are used to test each IC chip at the wafer level, ensuring that subsequent value added production uses only those chips that work.

Applications of tungsten in medicine and dentistry

For the mother of the family, ITIA's story details a number of important appointments, including the use of tungsten in medical equipment. For example, she went to the hospital for a computed tomography (CT) scan of her spine to try to determine the cause of some chronic back pain.

While magnetic resonance imaging (MRI) may be more widely used today, CT equipment then and now could generate 3D images using X-ray tubes containing electrodes made of tungsten and rotating anodes made of tungsten or tungsten-rhenium alloys. In addition, tungsten is still used to shield the entire CT machine.

After a good report from a CT scan that showed no serious problems, the mom headed to the dentist's office for an appointment. There, panoramic X-rays were taken of all her teeth -- again, the tungsten anode came into play in the X-ray machine.

Calcium tungstate is used as a fluorescent material in X-ray films. In addition, the heavy protective apron mom wears is made of tungsten powder dispersed in latex, which protects her from radiation and is more environmentally friendly than lead.

Today, digital imaging is more common than using traditional X-ray film in a dentist's office, but the basic X-ray technique remains the same. Interestingly, in the United States, our dentists still use protective aprons made of lead. But wouldn't it be great if they switched to more environmentally friendly tungsten?

Back in 2007, mom had bad news: She needed a root canal! Most drill bits used by dentists for cleaning and molding are made of fine grained, extremely sharp edge carbide. What was true then, and still is true, is that this bit material produces less friction, which means less heat and less patient pain -- and finally, some good news for Mom.

Tungsten is used throughout the school year

That morning, the family's two children went to school by train. Its engines contain high-voltage switches, and its contact zone consists of copper-tungsten components that are resistant to flower erosion due to tungsten's high melting point.

Carbide wire drawing dies are used to make overhead contact lines for trains and all wires in engines. Thin copper plate parts for engines and transformers are die-cut using carbide tools. Today, the use of these tungsten is still standard.

While studying physics tests on the train, one of the kids read about the use of tungsten in the first wall material of a fusion reactor. The project, the International Thermonuclear Experimental Reactor (ITER), was in the planning stage and is still under construction. (You can read about the project at www.iter.org.

Looking out of the train window, the children saw an open pit coal mine that relied on cement tungsten carbide pipes, using giant shovels and other tools and systems. While the economics of coal have not been kind to the industry in recent years, the equipment is still used today for different types of mining, and tungsten carbide components are still used.

When they arrived at school, the son realized he had forgotten some supplies and asked to borrow a piece of paper and a ballpoint pen from his sister.

Of course, today laptops and mobile devices have replaced cushions and pens for many students. But in 2007 and now, tungsten-coated rolls are used to make paper, and carbide knives are used to precisely cut the paper of the writing board.

In addition, the corrosion-resistant carbide form of tungsten still forms the ball of the ballpoint pen -- precisely designed to provide just the right surface roughness in order to carry enough ink on the paper and roll without slipping.

Tungsten in leisure.

After a day of work that included a CT scan at the hospital, followed by a trip to the dentist's office and root canal treatment, the mother of the family finally took a break: After her date, she had a date to play a round of golf with some friends.

She checks her watch -- a gift from her husband, a highly scratch-resistant tungsten carbide model with a mechanical movement and tungsten heavy alloy parts that automatically closes the chain. Luckily, she may still be wearing the same watch today.

The golf outing gave the mother a chance to practice with her new driver, who had tungsten heavy alloy screws to improve performance, so she could make further progress on the 18 handicap. She was delighted with the new golf balls her husband gave her for her birthday. One of the outer layers inside the ball contains a tungsten shell that, when hit correctly, allows the golfer to apply a lot of spin to her shot.

Because of the cold weather and hard ground, she was also thankful for the carbide spikes on her golf shoes. Today, the use of tungsten such as this is one of many other technological advantages that golfers seek in their quest for perfection.

Meanwhile, after school, the daughter of the family and some of her friends went jogging, wearing weights on their hands and legs to improve their training efficiency. Now, as in 2007, the weights are typically made of tungsten, their high density provides weight in a compact package, and rely on the expertise of companies like Metal Cutting on how to cut tungsten.

That afternoon in 2007, my son met some friends at a youth club, where they were playing darts with professional-style darts made of tungsten heavy metal. This allowed (and still allows) a thin design and stable trajectory when throwing projectiles.

Application of tungsten in general industry

Throughout the day, the family's story referred to a wide range of other uses of tungsten in general industry - examples that are still completely relevant. These include:

A tungsten wire used for charged (corona) wires in laser printers and copiers

Carbide tools for machining titanium parts of automobile engine blocks and aircraft wing spars and landing gear

Polycrystalline diamond on tungsten carbide inserts, CFRP used to cut aircraft components such as wing enclosures

Heavy road-building machinery equipped with carbide chisels and other tungsten bases

High performance transformers and power station switches made of copper and tungsten

Wood chip cutting machines with carbide knives are more durable than steel

Go home at the end of a tungsten day

When the family gathers at home at the end of the day, there are more uses for tungsten hidden in plain sight. For example, mom and daughter have hung some new curtains that are fire-resistant due to sodium metatungstate embedded in the fabric.

Father and son were involved in a DO-it-yourself project -- a new bathroom with tiles that reflect light thanks to tungsten oxide and tungsten metal in the glaze. The tools they used included carbide tile cutters and drills with carbide bits.

While Mom used a carbide knife sharpener to fix dinner, Dad (an enthusiast) tested one of his recent purchases - a simulated vinyl record player equipped with the following:

Tungsten counterweight for adjusting tone arm and suppressing vibration.

The four weight feet at the bottom are made of heavy alloy to suppress the impact of vibration on the turntable

After dinner, the family heads to the cinema to watch the latest wide-angle projection thriller, xenon short-arc lamps with tungsten electrodes sharp and bright.

While the family ended their day in the glow of tungsten lamps -- an application that owes its warm and welcoming glow to tungsten's resistivity but is less common today than energy-saving lamps and leds -- almost every other use of tungsten is equally relevant today.

Is there tungsten in your future?

Of course, this is just our view of how tungsten use has evolved over the past decade or so. However, we think you will agree that this comparison shows that tungsten remains one of the most widely used and beneficial refractory metals.

As a company that knows how to cut tungsten and optimize its use, Pride can help you determine if characteristics such as its high melting point make it the right material for your current or planned application.

Please contact us at zhang@pride-cnc.com