Defective 3D Printing For Great Strength

February 2, 2022 by Al Williams 6 Comments

Most of us want our 3D prints to be perfect. But at Cornell University, they’ve been experimenting with deliberately introducing defects into printed titanium. Why? Because using a post-print treatment of heat and pressure they can turn those defects into assets, leading to a stronger and more ductile printed part.

The most common ways to print metal use powders melted together, and these lead to tiny pores in the material that weaken the final product. Using Ti-6Al-4V, the researchers deliberately made a poor print that had more than the usual amount of defects. Then they applied extreme heat and pressure to the resulting piece. The pressure caused the pores to close up, and changed the material’s internal structure to be more like a composite.

Reports are that the pieces treated in this way have superior properties to parts made by casting and forging, much less 3D printed parts. In addition, the printing process usually creates parts that are stronger in some directions than others. The post processing breaks that directionality and the finished parts have equal strength in all directions.

The hot isostatic pressing (HIP) process isn’t new — it is commonly used in metal and ceramic processing — so this method shouldn’t require anything more exotic than that. Granted, even cheap presses from China start around $7,000 and go way up from there, but if you are 3D printing titanium, that might not be such a big expenditure. The only downside seems to be that if the process leaves any defects partially processed, it can lead to fatigue failures later.

We wonder if this development will impact all the car parts being printed in titanium lately. If you need something to print in titanium, consider hacking your rib cage.

Bugatti Concept Car Shows 3D Printed Strength

January 31, 2021 by Al Williams 30 Comments

We doubt you’ll be driving a Bugatti Bolide anytime soon. It’s a bit of a showy concept car, and it really is pushing some limits on what you can 3D print in an automobile. As you can imagine, they aren’t printing car parts out of ABS or PLA. According to The Drive, the prints use selective laser melting with titanium to make some impressively strong and light parts.

It isn’t just the material that makes the 3D prints strong. Bugatti actually patented the internal structure of some parts which are almost bone-like. By having the parts largely hollow, the weight is cut. But fine internal structure creates very strong parts. How strong? A 3.52 ounce pushrod can handle up to 3.85 tons. The printed titanium is apparently heat-treated to increase its resistance to fracture strains.

In addition to titanium, some of the concept car’s parts are printed ceramic which insulates some components from heat. The printing process can apparently get resolutions down to 0.1 mm. Many parts are quite lightweight including a 0.48 mm wheel that with supports weighs in at about 100 grams.

If you want to get into having a project car, we’d suggest something more modest. Even if you want to 3D print a titanium part for your ride, we’d still start a little smaller.

Geocaching On Mars: How Perseverance Will Seal Martian Samples With A Return To Earth In Mind

July 30, 2020 by Dan Maloney 23 Comments

With the roughly 20-day wide launch window for the Mars 2020 mission rapidly approaching, the hype train for the next big mission to the Red Planet is really building up steam. And with good reason — the Mars 2020 mission has been in the works for a better part of a decade, and as we reported earlier this year, the rover it’s delivering to the Martian surface, since dubbed Perseverance, will be among the most complex such devices ever fielded.

“Percy” — come on, that nickname’s a natural — is a mobile laboratory, capable of exploring the Martian surface in search of evidence that life ever found a way there, and to do the groundwork needed if we’re ever to go there ourselves. The nuclear-powered rover bristles with scientific instruments, and assuming it survives the “Seven Minutes of Terror” as well as its fraternal twin Curiosity did in 2012, we should start seeing some amazing results come back.

No prior mission to Mars has been better equipped to answer the essential question: “Are we alone?” But no matter how capable Perseverance is, there’s a limit to how much science can be packed into something that costs millions of dollars a kilogram to get to Mars. And so NASA decided to equip Perseverance with the ability to not only collect geological samples, but to package them up and deposit them on the surface of the planet to await a future mission that will pick them up for a return trip to Earth for further study. It’s bold and forward-thinking, and it’s unlike anything that’s ever been tried before. In a lot of ways, Perseverance’s sample handling system is the rover’s raison d’être, and it’s the subject of this deep dive.

Continue reading “Geocaching On Mars: How Perseverance Will Seal Martian Samples With A Return To Earth In Mind” →

Titanium Coating Is Actually Pretty Straightforward

January 8, 2020 by Lewin Day 28 Comments

[Justin] enjoys tinkering in his home lab, working on a wide variety of experiments. Recently, he’d found much success in coating objects with thin layers of various metals with the help of a DC sputtering magnetron. However, titanium simply wouldn’t work with this setup. Instead, [Justin] found another way.

As it turns out, coating with titanium is quite achievable for even the garage operative. Simply run current through a titanium wire, heating it above 900 degrees in a vacuum. This will create a shower of titanium atoms that will coat virtually anything else in the chamber. [Justin] was able to achieve this with little more than some parts from Home Depot, a vacuum pump, and a cheap glass jar. He was able to produce a nice titanium oxide finish on a knife blade, giving that classic rainbow look. Coating crystals was less straightforward, but the jet black finish achieved was impressive nonetheless.

[Justin] plans to upgrade his vacuum rig further, and with better process control, we’d expect even better results. The earlier work is also very relevant if you’re interested in creating fine coatings of other materials. Video after the break. Continue reading “Titanium Coating Is Actually Pretty Straightforward” →

Wearable Superconductors

August 17, 2017 by Adam Fabio 34 Comments

What do you do with a discarded bit of superconducting wire? If you’re [Patrick Adair], you turn it into a ring.

Superconducting wire has been around for decades now. Typically it is a thick wire made up of strands of titanium and niobium encased in copper. Used sections of this wire show up on the open market from time to time. [Patrick] got ahold of some, and with his buddies at the waterjet channel, they cut it into slices. It was then over to the lathe to shape the ring.

Once the basic shape was created, [Patrick] placed the ring in ferric chloride solution — yes the same stuff we use to etch PC boards. The ferric chloride etched away just a bit of the copper, making the titanium niobium sections stand out. A trip through the rock tumbler put the final finish on the ring. [Patrick] left the ring in bare metal, though we would probably add an epoxy or similar coating to keep the copper from oxidizing.

[Patrick] is selling these rings on his website, though at $700 each, they’re not cheap. Time to hit up the auction sites and find some superconducting wire sections of our own!

If you’re looking to make rings out of more accessible objects, check out this ring made from colored pencils, or this one made from phone wire.

It’s Time For Direct Metal 3D-Printing

May 19, 2016 by Moritz Walter 75 Comments

It’s tough times for 3D-printing. Stratasys got burned on Makerbot, trustful backers got burned on the Peachy Printer meltdown, I burned my finger on a brand new hotend just yesterday, and that’s only the more recent events. In recent years more than a few startups embarked on the challenge of developing a piece of 3D printing technology that would make a difference. More colors, more materials, more reliable, bigger, faster, cheaper, easier to use. There was even a metal 3D printing startup, MatterFab, which pulled off a functional prototype of a low-cost metal-powder-laser-melting 3D printer, securing $13M in funding, and disappearing silently, poof.

This is just the children’s corner of the mall, and the grown-ups have really just begun pulling out their titanium credit cards. General Electric is on track to introduce 3D printed, FAA-approved fuel nozzles into its aircraft jet engines, Airbus is heading for 3D-printed, lightweight components and interior, and SpaceX has already sent rockets with 3D printed Main Oxidizer Valves (MOV) into orbit, aiming to make the SuperDraco the first fully 3D printed rocket engine. Direct metal 3D printing is transitioning from the experimental research phase to production, and it’s interesting to see how and why large industries, well, disrupt themselves.

Continue reading “It’s Time For Direct Metal 3D-Printing” →

Hackaday Links: October 12, 2014

October 12, 2014 by Brian Benchoff 17 Comments

Remember in the late 90s and early 2000s when everything had blue LEDs in them? Blinding blue LEDs that lit up a dark room like a Christmas tree? Nobel prize. There’s a good /r/askscience thread on why this is so important. The TL;DR is that it’s tough to put a p-type layer on gallium nitride.

Have a Segway and you’re a member of the 501st? Here’s your Halloween costume. It’s a model of the Aratech 74-Z speeder bike, most famously seen careening into the side of trees on the forest moon of Endor.

[Andrew] needed something to do and machined an iPhone 5 out of a block of aluminum. Here’s the video of icon labels being engraved. The machine is a Denford Triac with a six station auto tool changer. He’s running Mach3, and according to him everything – including the correct tooling – cost far too much money.

Another [Andrew] was working the LEGO booth at Maker Faire New York and has finally gotten his LEGO Mindstorms Minecraft Creeper build written up. Yes, it’s probably smarter than your average Minecraft Creeper, and this one also blows up. He also had a physical version of the classic video game from 1979, Lunar Lander. Both are extremely awesome builds, and a great way to attract kids of all ages to a booth.

[Wilfred] was testing a titanium 3D printer at work and was looking for something to print. The skull ‘n wrenches was a suitable candidate, and the results are fantastic. From [Wilfred]: “Just out of the printer the logo looks amazing because it isn’t oxidized yet (inside the printer is an Argon atmosphere) Then the logo moves to an oven to anneal the stress made by the laser. But then it gets brown and ugly. After sandblasting we get a lovely bluish color as you can see in the last picture.”

The folks at Lulzbot/Aleph Objects are experimenting with their yet-to-be-released printer, codenamed ‘Begonia’. They’re 2D printing, strangely enough, and for only using a standard Bic pen, the results look great.

Everyone is going crazy over the ESP8266 UART to WiFi module. There’s another module that came up on Seeed recently, the EMW3162. It’s an ARM Cortex M3 with plenty of Flash, has 802.11 b/g/n, and it’s $8.50 USD. Out of stock, of course.