Zirconium: Not Just For Rings and Things

If you’ve ever watched a shop at home television channel or been in the market for inexpensive jewelry, then you’re probably familiar with cubic zirconia, the synthetic alternative to diamonds. According to Wikipedia, cubic zirconia has been the most “economically important competitor for diamonds since 1976.” More generally, though, zirconium is a chemical element (Zr) that is found in nature within the earth’s crust and sea water. Its applications are much wider-ranging than jewelry.

Zirconium’s global usage shows that it is predominantly used within the field of technical ceramics. For instance, 54% of China’s zirconium consumption goes towards ceramics. Zirconium is extremely hard, stable, and dense. It is overwhelmingly strong. Its fine grain size makes it perfect for creating sharp blades. Ceramic knives are one of the latest crazes in kitchenwares, for instance. In addition to sharpness, zirconium can be used to create porous ceramic filters and diffusers for washing and spraying functions. Its durability, density, and corrosion resistance allows it to be used in applications that require dealing with acids.

I stumbled across this page, which gives a lengthy overview of zirconium, from its global availability and application to end users and producers.

Zircon consumption, like that of most other commodities, has been hit by the global economic slowdown. However, supply (both existing and potential), too, appears to have been impacted equally, if not more, severely. Not only have a number of suppliers in both Africa and Australia (for example, Australian Zircon NL (Bloomberg Ticker—AZC:AU)) been facing financial challenges, with consequent decreases in production, but other producing countries have also been facing limitations on production. Indonesia, in particular, saw zircon production fall more than 40% in 2008 from the level in 2007.

In addition, Refractron has an excellent page about a special kind of zirconium, Yttria Tetragonal Zirconia Polycrystal (Y-TZP).

Y-TZP has a material density of greater than 6.0 g/cc, a maximum operating temperature of 2000 C. This material has the highest flexural strength of the zirconia materials particularly when processed using a HIP (Hot Isostat Press). Values are 900 MPa and 1400 MPa (HIP'd). The hardness is 13-13.5 GPa, Fracture Toughness is 8.0 MPa-m1/2 and Thermal expansion (C.T.E.) is 10.2 x E6/ degree C).

So the next time you’re up late and watching QVC shilling cubic zirconium rings, remember that what you’re actually seeing is a product related to technical ceramics.

A Neat Application of Porous Ceramics

Has your space ever been invaded by dust mites, mold, or moisture damage? Well, a Japanese company has created a product called the dehumEGGifier, which utilizes porous ceramics technology to reduce ambient humidity without the intrusion of a noisy, bulky dehumidifier.

The dehumEGGifier, as you can see above, is a rather small, egg-shaped device crafted out of a porous ceramic material that houses silica gel beads. As the silica gel beads absorb moisture through the porous shell, the blue base turns to pink. Once the base is pink, you are to micorwave the egg for about ten minutes, which will desiccate the beads readying the dehumEGGifier ready for re-use.

The dehumEGGifier seems to take advantage of a specific property of ceramics: Namely, that porous ceramics are generally made by fusing metal oxide grains using a porcelain bond, which reates a strong, uniformly porous and homogeneous structure. The resulting material is naturally hydrophilic (that is, having a natural tendency to mix with water), which results in an impressively even transmission of liquid. Porous ceramics--besides having applications in quirky Japanese consumer products--can be used for applications such as spraying, oven firing, and ultrasonic cleaning. For some more information about porous ceramics, check out this page on Refractron's website.

Dr. Harry L. Tuller, MIT professor, to give lecture at Alfred University

Tuller, who is a professor of ceramics and electronic materials in the Department of Materials Science and Engineering, and head of the Crystal Physics and Electroceramics Laboratory (what an elegant title!) at the MIT, will give a talk entitled “Electroceramics: Technology for the Future." His talk is scheduled for 11:20am on 22 October.

According to Alfred University, Professor Tuller's talk will center on,

what makes electroceramics particularly attractive and/or essential for insuring rapid progress in all of these areas, focusing on their high figures of merit in information and energy transduction and in their thermal, mechanical, and chemical stability. Examples are provided to illustrate where electroceramics are likely to play a particularly strategic role in the future.

It looks like an extremely interesting lecture. I hope to see you all there!

The 11 Best Ceramics Papers?

The American Ceramics Society is a great resource for information, news, and events concerning the modern technological deployment of ceramics. It has been around since 1898 and it boasts more than 9,500 scientists, engineers, researchers, manufacturers, plant personnel, educators, and others as its members.

Its website is a veritable hub of great information about technological developments and upcoming events in the ceramics community. But it’s not just the future it looks toward. It’s also a great resource for learning about ceramics. One great page of the site is its 11 Best Papers. It includes links to a .pdf of each paper. The bibliography covers topics ranging from the structure and stress resistance of glass to the future of diamond ceramic coating. The papers seem selected for their excellence and not necessarily their modern-day relevance as their dates of publication range from 1934 to 1993. It is, undoubtedly, a great resource, though, to get a good perspective on the history of advanced ceramics studies and an eye for where it’s heading.

1. B. E. Warren, “X-Ray Determination of the Structure of Glass,” J. Amer. Cer. Soc., 17 (12) 249-254 (1934).
2. W. D. Kingery, “Factors Affecting Thermal Stress Resistance of Ceramic Materials,” J. Amer. Cer. Soc., 38 (1) 3-15 (1955).
3. S. M. Wiederhorn, L. H. Bolz, “Stress Corrosion and Static Fatigue of Glass,” J. Amer. Cer. Soc., 53 (10) 543-548 (1970).
4. G. Anstis, P. Chantikul, B. Lawn, D. B. Marshall, “A Critical-Evaluation of Indentation Techniques for Measuring Fracture-Toughness .1. Direct Crack Measurements Materials,” J. Amer. Cer. Soc., 64 (9) 533-538 (1981).
5. D. R. Clarke, “On the Equilibrium Thickness of Intergranular Glass Phases in Ceramic Materials,” J. Amer. Cer. Soc., 70 (1) 15-22 (1987).
6. F. F. Lange, “Powder Processing Science and Technology for Increased Reliability,” J. Amer. Cer. Soc., 72 (1) 3-15 (1989).
7. K. E. Spear, “Diamond Ceramic Coating of the Future,” J. Amer. Cer. Soc., 72 (2) 171-191 (1989).
8. A. G. Evans, “Perspective on the Development of High-Toughness Ceramics,” J. Amer. Cer. Soc., 73 (2) 187-206 (1990).
9. P. F. Becher, “Microstructural Design of Toughened Ceramics,” J. Amer. Cer. Soc., 74 (2) 255-269 (1991).
10. L. L. Hench, “Bioceramics - From Concept to Clinic,” J. Amer. Cer. Soc., 74 (7) 1487-1510 (1991).
11. N. S. Jacobson, “Corrosion of Silicon-Based Ceramics in Combustion Environments,” J. Amer. Cer. Soc., 76 (1) 3-28 (1993).

How do you become a ceramics engineer?

When you think of ceramics, pottery and coffee mugs may be the first things that come to mind. But ceramics play a big role in industrial design and engineering. Ceramics engineering is actually a fast-growing, lucrative career field. Like most professional, technical careers, the best first step to becoming a ceramics engineer is by going to a ceramic engineering program. A ceramic engineering program can help to prepare you for the field, which is ever-changing and technically demanding. Ceramics play a primary role in the design of many products because the materials have the ability to increase or decrease magnetic, thermal, and electrical properties. This property of ceramics makes them incredibly valuable to the engineering process of millions of products. Ceramics are also low-cost compared to other common industrial materials.

Students in ceramic engineering programs have the opportunity to be part of a field that impacts environmental issues like recycling and energy conservation. They also learn basic science and engineering while simultaneously growing their analytical and computational skills.

In a ceramic engineering program, you will develop a comprehensive understanding of ceramic materials, including their behavior in different temperatures, their processing and structure, and their industrial applications. A good program will teach you about the mechanical properties of ceramic materials and their atomic scale properties. Many programs require students to take a certain number of elective courses outside the area of ceramics engineering, which broaden your educational horizons.

Ceramic engineers work with inorganic, nonmetallic materials to develop materials that support products and systems that impact all our lives. For instance, fiber optic materials are critical to the telecommunications industry, and cell phones would not be possible without the development of electronic ceramics.

While there are ceramic engineering programs at many colleges and universities, here are some notable programs to consider:

• Alfred University’s Ceramic Engineering Graduate Programs
• Penn State's Materials Science and Engineering Department
• Rutgers' Materials Science and Engineering Program
• and Clemson's Materials Science and Engineering Graduate Programs

And don't forget! If you're interested in ceramics engineering, don't miss out on the Dean of the NYS College of Ceramic's upcoming talk on glass.

Something To Do On A Thursday Night This Fall?

If you're going to be in upstate NY on September 10, you might want to drop by Alfred University for a talk by the dean of the New York State College of Ceramics, William LaCourse. He will be giving a lecture entitled, "Glass: Old Dog, New Tricks."

The lecture is slated to commence at 12:10 PM at the Powell Campus' Nevins Theatre. For more information, you should contact the New York State College of Ceramics at Alfred University.