Tuesday, July 31, 2012
Monday, July 30, 2012
Saturday, July 21, 2012
I need to get my hands on a titanium hammer. I can't quite wrap my head around the 'but it hits just as hard' part of the design. Yeah, I get that a lower mass object would be easier to accelerate, but I would think that the lower mass object - the titanium hammer - wouldn't deliver nearly the same amount of force.
I love seeing the various steps involved in the manufacturing process here, though. It's gorgeous to see each step along the way - especially the investment casting. Gorgeous.
Has anybody out there actually gotten to use a titanium hammer? If so, wanna give a report?
The imagery here of chocolate sauce just rolling right off of white shoes - a particularly good color choice for the product demo - is stunning. For a brief while I even thought I understood what was happening - clearly the material is a nonpolar compound. Water's polar; anything nonpolar would 'repel' the water.
And then they started dumping oil on the product with equal success. Clearly I have some learning to do before I understand just what makes something super hydrophobic.
Saturday, July 14, 2012
The BBC series Bang Goes the Theory markets itself as sort of a shorter-form, British Mythbusters, but tends toward just answering simple questions or showing off science tricks (melting glass in a microwave, inflating a huge balloon in just one breath, etc). Here they look at why gold is used in electronics (like the presenter's cell phone) if it's so expensive (1000 per ounce according to the presenter).
I'm not entirely sold on the explanation that he gives - regarding simply the number of protons in the nucleus - because that would mean all large atoms would be non-reactive. I think there's something about gold's completely full d orbital, but explaining quantum mechanics and the electron orbital theory is probably a bit beyond the scope of the television programme (see, British spelling?).
It does, however, do a great job showing the kinds of things that we look at in materials science when we explore the activity series. Gold is very, very low on the activity series - down there with platinum and silver, all used for jewelry. Wonder if there's some reason for that...
Oh, I tried this experiment in class once. Dropped my gold wedding ring into concentrated hydrochloric acid and hoped. Turns out it worked just fine, but my wife wasn't too thrilled to hear about the experiment after the fact, so I don't do that anymore even though I'm pretty sure the science is solid.
Friday, July 13, 2012
Need a great application for non-Newtonian fluids? Look no further! I also try to stress the importance of the repeated testing and research that these students did to turn an idea into a useful product. I also kick myself when wondering why I didn't think of that.
Thursday, July 12, 2012
Monday, July 9, 2012
Sunday, July 8, 2012
Becky Heckman (one of our ASM master teachers) showed me her son's new evoSHIELD wrist guard this morning. He already had one but had just gotten a new one, and she made him wait to fit it until I could see the thing fresh out of its package. The wrist guard (you can see specifically that product in the video below) is a neoprene sleeve and a plastic insert. The insert is initially sealed in a thick, assumedly air-tight foil package. When the package is opened, the insert is flexible like a gel. The insert is then placed in the sleeve and worn. As air reacts with the insert, the insert turns into a rock-hard plastic over the next twenty or so minutes in an exothermic process. Because the flexible insert is worn on the player's wrist as it hardens, the protection is almost perfectly fitted to the player's wrist forever, giving the player good - according to data I found online - protection against impact.
The company also offers similar products for hockey, football, baseball, softball, lacrosse, and even shooting pads. I'm fascinated by this and want to know way more science than what their website provides.
Anybody have any ideas on the science here?
Kinda cool that it's a university project gone right, too.
Friday, July 6, 2012
I think we can all agree that our current energy needs - and the needs predicted by our perpetually increasing demand - are untenable in the long run. Whether a scientist chooses to attack the problem from the supply end (more wind farms, increased nuclear production, clean coal, hydrofracking, gerbils on tiny wheels) or the demand end (fluorescent lights, home insulation, adjusting the thermostat, solar-powered laptops),he or she will find even their smallest success in quick and huge demand if they look to be afforadble, scaleable, and effective.
Here we see Donald Sadoway's TED talk on his development of a liquid metal battery (magnesium / molten salt / antimony) as well as his mentoring of and dependence on graduate students and post-doctoral students, choosing these intelligent but inexperienced folks rather than the more experienced battery experts whose thinking might be a little more regimented, a little less willing to experiment.
I have lots of questions about the chemistry here - how easily are the metals sourced, in the larger collections of batteries how does the heat dissipate or does it need to, what salt is in the center, how safe are the batteries, how quickly can the batteries deliver power and how quickly can they be recharged - but I am certainly intrigued.
Thursday, July 5, 2012
Materials to be used in the human body have a number of difficult and often contradictory requirements. The materials must be chemically and biologically acceptable by the human body, light weight, durable, and ideally - but of lower import - inexpensive.Here we can see a new polymer (lactic/glycolic acid copolymer - PLGA) that can simply biodegrade and be metabolized by the human body once the material is no longer needed.
Smelting of ores into native metals is an old technology. In a blast furnace an oxygen-poor material (carbon, typically) is introduced into an ore under white hot conditions where the carbon grabs the oxygen leaving purer native metals leaving slag behind.
In this video we get an initial animation of the blast furnace itself. Then we get footage of the native metal and a discussion of the next steps for the carbon-rich iron that is produced.
Again scientists look to the natural world for an ideal material, this time looking at crabs to mimic the chitin attachment between the crab's shell and underlying musculature. This material - surgilux - is a "thin polymer film based on chitin" that 'melds' to the flesh when heated via infrared light.
According to Dr John Foster in the video, the melding is simple, cost-effective, anti-microbial, non-scarring, and non-dependent on the surgeon's skill level.
Well that's a simple goal: something lighter than aluminum and stronger than steel.
Turns out that such a material is possible as shown here by Afsaneh Rabiei who has made a composite metal foam - an aluminum matrix with hollow steel spheres. In this video we see the production of and testing of such a material. We then get some possible uses of the metal foam.
Most of our students are at least passingly familiar with iron, copper, aluminum, even gold, silver, and mercury, but most of them - and many of us as well - are far less familiar with other metals, many of which are absolutely essential for many of our industrial processes.
Here we get a look at the mining and processing of beryllium ore into beryllium dust - which is sadly not shown in the video but is given a sodium chloride stand-in.
In the next video we get a look at how the beryllium powder is melting and cast into blanks, how the blanks are then processed into mirrors for the James Webb space telescope, how the mirrors are checked for defects and then partially hollowed out to reduce their weight.
Monday, July 2, 2012
I'll admit that lawn bowling balls might not look like the most technologically advanced piece of equipment that your students could ever explore, but the steps that go into creating a high-quality ball here are pretty impressive - from molding the melamine to carving to polishing to finally testing the finished product.
In our workshops we use a procedure that I greatly prefer to the one shown in this video, but the 'trick' of turning pennies to gold never gets old. Sure it's a brass alloy of copper and zinc, but it looks like magic.
Materials Science is all about choosing the right material for the right use. That might mean that you need to find the cheapest material, the most durable, the most flexible, the most whatever. This video explores the challenge of finding the least environmentally damaging material, particularly for use in electronics so that we aren't poisoning the workers who make or recycle the electronics.
It's not exactly Harpo Marx's finest performance, but here we get a wordless demonstration of a wood 'welding' machine that sends radio frequencies into a wood/glue bond setting the glue in seconds rather than hours.
I promise that the title is as I've typed it above. The lack of a helping verb or a contraction bothers me, but that's how the video is titled.
Here we follow the production of ductile iron pipes from the sourcing (primarily recycled iron/steel), smelting, mixing, casting, and finishing the pipe. The spinning mold is particularly fascinating.
This video gives us a look at how NASA uses carbon nanotubes to produce a surface that reflects an absolute minimum of lightwaves for their optical instruments in space. The video looks at the structure of the nanotubes as well as some of the durability tests that they have conducted to make the nantube coatings more durable.
Graphite is one of the allotropes of carbon - along with diamond and buckminsterfullerenes (buckyballs). Graphite exists as a series of hexagonal-based carbon layers, a single layer of which is known as graphene, the exploration of which lead to the awarding of the 2010 Nobel Prize in Physics.
In this video the structure and electrical properties of graphene are explained in very simple, udnerstandable language.
The Top Thrill Dragster in Sundusky, Ohio's Cedar Point is a marvel of engineering - and was especially so when it was introduced in 2003. The force and materials required to accelerate the train at the speeds needed to peak the tower required some pretty impressive materials. That aspect shows up at about 3:10 into the above video.
Biomimetics is a fascinating field in which scientists take inspiration from the natural world to improve out technologies. Here a video from the National Science Foundation looks at one of the major struggles that scientists are trying to overcome in making artificial spider silk - particularly at the difficulty in storing liquid spider silk until it is solidified after it comes through the spinnerets.
The BBC show Brainiac produced some outstandingly entertaining and sensational experiments involving vaguely science topics. They tended toward explosions and chucklesome comments along the way.
Sadly, however, at least some of their experiments - including the one above - were exaggerated with conventional explosives to make things a little more exciting than they would be in real life. You can check out more details and the stories reporting their fraudulent behavior over on my other blog. I still show this video in class, however, because I enjoy reminding students that just because they see it on tv or on YouTube doesn't necessarily make the explanation right or real.
I also follow the video up with this one which is - as far as I can tell - real.
It is, however, a little less spectacular.