Diamonds may be the hardest substance on earth, but not necessarily the most durable. When it comes to grinding applications, this super-hard form of carbon tends to dissolve in iron at high temperatures. In comes thermally-stable boron nitride, which, in cubic form, is the second hardest substance. Norton, Co, Worcester, MA, manufactures cubic boron nitride (CBN) grinding wheels for use in high-volume, tight-tolerance applications. Compared to aluminum oxide abrasive wheels with typical cost of $150, these super-abrasive CBN grinding wheels can run around $5,000—but as productive as 40 conventional wheels. The extraordinary temperatures and pressures—up to 2000°C and 500,000 atmospheres—required for making CBN contribute to its high cost. However, researchers at Shandong University in Jinan, China, have recently synthesized 30nm-wide BN crystals at only 480°C in atmospheric pressure, using boron tribromide and lithium nitride within a benzene solvent. The next challenge will be to increase the crystals to industrial size with these methods. A paper detailing the research is available at Circle 182—Chemistry of Materials, or connect directly at www.RSLeads.com/?111df-182. Circle 183—Norton Co, or connect at www.RSLeads.com/?111df-183

With the current environmental focus on alternative fuel sources for automobiles, another contender has appeared from the past. In the early years of the Cold War, there was a secret fuel research program concentrating on hazardous boron-hydrogen combinations called boranes. These compounds produced up to four times the energy, weight for weight, as high-octane hydrocarbon fuels, yet their production and handling was so dangerous and expensive that the fuel research was abandoned in the early 1960s. Commercialization along less volatile lines was continued in paper-making processes, but more recent ventures have returned to early research veins. Millennium Cell, Eatontown, NJ, boasts a proprietary process called Hydrogen on Demand “that safely generates pure hydrogen or electricity from environmentally-friendly raw materials.” Hydrogen’s energy potential is stored within the chemical bonds of sodium borohydride (a derivative of natural borax) and sodium hydroxide dissolved in water. Particular catalysts can then be used to release this energy in the form of combustible hydrogen or directly-produced electricity. A prototype HOD fuel system has been accepted for evaluation by researchers at Ford Motor Company in Dearborn, MI for use as a hydrogen source either for a fuel cell or in an internal combustion engine. Circle 184—Millennium Cell, or connect at www.RSLeads.com/?111df-184