Small & Mighty
Some said it couldn’t be done. But researchers have found a way to disperse nanoparticles into metal castings to achieve great strength in lightweight alloys.
Shannon Wetzel, Senior Editor
its potential doubted by the industry it is meant to benefi t. For Xiaochun Li, professor at Univ. of Wisconsin- Madison, Madison, Wis., and a hand- ful of others, research into the use of nanomaterials to reinforce metal castings held these challenges. A nanometer is one billionth of a meter—think the size of a marble com- pared to the size of the Earth. Bacteria typically measures at a thousand nano- meters. Ants are millions of nanometers long. Li and his group manipulate particles 30 nanometers in size. Nanoparticles are being developed
W
for use in medicine to fi ght cancer cells, as a catalyst to break down volatile organic compounds in the air, and in polymers for lightweight but strong sporting equipment. When successfully incorpo- rated in metalcasting, nanopar- ticles can greatly increase the strength of lightweight alloys like magnesium and aluminum. But when Li first began
work on using nanoparticles in casting in 2003, many in the scientifi c community and industry didn’t think it was possible to keep nanopar- ticles uniformly dispersed in
May/June 2010
orking in a research lab can be a lonely as- signment, particularly when the subject mat- ter is unknown and
molten metal as it solidifi es. “It was very diffi cult to convince oth-
ers that nanoparticles would be so ef- fective [in metalcasting] because a lot of traditional scientifi c study showed that it would be diffi cult to trap a particle that is so small,” Li said. “Most nanotechnol- ogy in metals relies on powdered metal and sintering, not solidifi cation. They think solidifi cation will push nanotech- nology out. Well, some particles will push out, but some will stay.” With seed money from the American
Foundry Society, Schaumburg, Ill., and later the National Science Foundation, research pressed on, and nanotechnol- ogy began to shift from implausible to possible to coming soon. In February, nanocomposite casting technology research was granted an estimated $10.1 million over fi ve years from the National Institute of Standards and Technology’s Technology Innova-
tion Program (TIP), which provides funding for high-risk, high-reward research in areas of critical national need in the U.S.
The estimated $10.1
million budget includes $4,860,000 (direct cost) from the institute and $5.24 million matching support from team partners. The new commitment to nano- composite research in metalcasting could mean the technology will be production-ready soon, according to Dave Weiss of research partner Eck Industries, Manitowoc, Wis. “We think this is something that
could be reasonable to go into produc- tion at least in some products in three to fi ve years,” Weiss said. “It’s defi nitely not pie in the sky anymore.”
Particles Pack a Punch Nanoparticles bridge bulk material
“ We think this is something that could be reasonable to go into pro-
”
duction at least in some products in three to fi ve years. It’s defi nitely not pie in the sky anymore. —Dave Weiss, Eck Industries
with atomic or molecular structures. Bulk material, such as alumi- num, has constant physical properties regardless of size. But at the nano scale, the properties of a material change. Research- ers are studying ways to achieve specifi c properties, such as high strength, found in materials at the nano-scale while maintain- ing the properties inherent in the bulk material. With in-kind funding from Eck, Oshkosh Corp., Oshkosh, Wis., the Univ. of Wisconsin-Madison, Nano-
Metal Casting Design anD PurChasing 33
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68