Letters to the Editor
- PDF / 521,793 Bytes
- 1 Pages / 576 x 777.6 pts Page_size
- 40 Downloads / 186 Views
New Superhard Materials are Becoming a Reality To the Editor: I read MRS Bulletin regularly and very often find interesting papers. One such article is David Tete?s article on the computational alchemy of superhard materials in the January 1998 (page 22) issue of MRS Bulletin. It is pleasant that this report by a young PhD [graduate] contains an extensive bibliography (more than 100 references) including some Russian works. However, unfortunately, the author's attention to nanostructured materials is very limited. If s only at the end where he mentions some results concerning superlattices problems. Several years ago German, American, Swedish, and Russian investigators have demonstrated the high hardness values (more than 50-60 GPa) for multilayer films based on high-melting point compounds such as nitrides, borides,
standing hardness principles, and develand carbides (see my review in the /. Mater. Sci. 32 [1997] p. 4463). It is also inter- opment of computational hard materials esting that in the case of nanostructured science, lies ahead. bulks of TiN the hardness value is also Rostislav A. Andrievski 1.5-2 times higher compared with that for Institute for New Chemical Problems Russian Academy of Sciences conventional sintered or hot-pressed TiN (Nanostruct. Mater. 9 [1997] p. 607). It is worth pointing out that in the case of Advertisers in This Issue nanostructured metals (copper, palladium, Page No. nickel, silver, and others) the hardness Chemat Technology, Inc. 43 increasees on average four to six times as a EDAX, Inc. 3 result of grain size decrease. Is it possible Electrochemical Society 5 to move this hardness increase from ductile Gatan, Inc. Inside back cover solids to brittle ones such as high-melting Inside front cover High Voltage Engineering point compounds and to reach the diaHuntington Laboratories Outside back cover mond hardness value? Now there are only LANSCE 56 separate results obtained on multilayer VAT, Inc. 8 films such as TiN+ZrN, TiN+NbN, and Virginia Semiconductor, Inc. 7 TiN+VN which confirm the reality of a Voltax, Inc. 8 new type of superhard materials. The hard For free information about the products and services offered in this issue, fill out and mail the Reader Service work for creating such superhard materiCard, or FAX it to 312-922-3165. als, including synthesis, processing, under-
The New Age of x-ray Microanalysis is here... (the Age of Sapphire. The Age of: # The best standard resolution of any EDS detector # Sapphire reliability backed by a three-year warranty # Optimum sensitivity with 20,000:1 peak-to-background ratio Now leading in advanced detector technology, EDAX developed the Sapphire detectors for the 21st century, with performance standards beyond your expectations and as an instrument to help provide solutions to all your x-ray microanalysis problems. With the Sapphire detectors you can do it all, without having to make compromises. It's a new age in x-ray microanalysis... the Age of Sapphire. Call EDAX today.
Sapphire. A Shining Example of Peak Performance. 9
Data Loading...
