Structure Control of Aluminum Alloys by Means of Heat Time Melt Treatment pra-0093

Full Title New Technology for Structure Control and Mechanical Properties Improvement of Aluminum Alloys by Means of Heat Time Melt Treatment Tech Area / Field

MAT-ALL: Materials / High Performance Metals and Alloys

PHY-STM: Physics / Structural Mechanics

Brief Description of Technology New technology has been developed for production of castings, ingots and granules of aluminum alloys with grain refinement structures and high mechanical and service properties. Traditionally, such materials are obtained by rapid crystallization or the alloying of aluminum alloys with small additions grain refiners, such as refractory metals or surface active elements. Our technology contains the heat time treatment of the melts and does not break the working cycles. The advantage of this method consists in the simplicity: it requires no specific apparatus, and is cost effective.

The basis of our processing is the hereditary influence of a liquid state on a solid state. According to the measuring physical properties of the melt, the liquid aluminum alloys represent a nonequilibrium microheterogeneous system consisting of the particles with the structure and the composition associated with the initial solid phase.

The variation in the heating temperature changes the heterogeneous state of the melts, that is the quantity and average size of the particles within them, and results in the change of the character of crystallization centers distribution. This phenomena is displayed more strongly in industrial multicomponent aluminum alloys because of the special character of intermetallic interaction forces in these melts.

Legal Aspects Experimental examinations of the new technology have successfully passed at the Institute of Metals Physics, Ural Division of Russian Academy of Science. Inventions certificates application for the new methods of production of some aluminum alloys have been approved in Russia.

Special Facilities in Use and Their Specifications None.

Scientific Papers Brodova I.G., Polents I.V., Popel P.S., “The Effect of Master Alloy Structure in Refinement of Aluminum Alloys with Zirconium,” The Physics of Metals and Metallography, V. 76, pp. 508-512 (1993).

Brodova I.G., Bashlikov D.V., Polents I.V., Yablonskikh T.I., “Effect in Additions on the Structure of Hypereutectic Silumin,” The Physics of Metals and Metallography, V. 79, No. 4, pp. 425-429 (1995).

Brodova I.G., Bashlikov D.V., “The increase in plasticity of aluminum silicon,” Light Metals, TMS, Las Vegas, pp. 879-882 (1995).

Brodova I., Polenz I., Bashlikov D., “The formation mechanism of ultradispersed phases in rapidly solidified aluminum alloys,” Nanostructured materials.V.6, No. 1-4, pp. 477-479 (1995).

I.G. Brodova, D.V. Bashlikov, I.V. Polents, O.A. Chikova, “Influence of heat time melt treatment on the properties of rapidly solidified aluminum alloys with transition metals,” Materials Science and Engineering (1997).

Diamond-Like, Carbon Coated Magnetic Heads for Recording and Reading Information pra-0094

Full Title Diamond-Like, Carbon Coated Magnetic Heads for Recording and Reading Information Tech Area / Field

INF-SIG: Information and Communications / Sensors and Signal Processing

MAT-CER: Materials / Ceramics

CHE-SYN: Chemistry / Basic and Synthetic Chemistry

Brief Description of Technology We have developed the technology and equipment for the sputtering of Diamond-like-carbon (DLC) coatings on the working surfaces of magnetic heads (video and audio) to improve their exploitation properties: to increase wear-resistance, to reduce the friction coefficient of head against tape, to increase the serving life of magnetic information carrier and improve the quality of information recording and reading. Special procedures are used in this technology to obtain good a adhesion of the coating to the head surface, and a high quality surface (relief is about 1- 1.5 nm).

The deposition takes place at sufficiently low temperatures (up to 60 °C), and the technology is highly productive and cheap. The technology and equipment has been developed, in part, according to the orders of foreign companies. Now the videorecorders with DLC coated heads are widely suggested.

We propose the further development of this direction of investigation. The main aims are the further reduction of a friction coefficient of head against tape, and the further increase of a head wear-resistance combined with a high-quality input signal. The last is a significant problem since DLC coating reduces the signal. Our recent results show that the aforementioned problems can be solved by means of special technology for the formation of a monomolecular fluorine organic compound layer and an alternative thickness DLC coating on the working surface of the head.

Legal Aspects We have the Russian patent, "Magnetic head" No. 2071125, dated May 26, 1993.

Special Facilities in Use and Their Specifications None.

Scientific Papers V. L. Arbuzov, I. Sh. Trakhtenberg, V. B. Vykhodets, A. E. Davletshin, S. A. Plotnikov, V. A. Nazarov, "Magnetic Head," Russian Federation Patent No. 2071125 (Dec. 27 1996).

I. Sh. Trakhtenberg, V. B. Vykhodets, V. L. Arbuzov, S. A. Plotnikov, A. E. Davletshin, "DLC coatings for video heads," Book of Abstracts of the 7th European Conference on Diamond, Diamond-like and Related Materials, Tours, France, No. 11.135. (Sept. 8-13, 1996).

V. L. Arbuzov, V. B. Vykhodets, I. Sh. Trakhtenberg, A. E. Davletshin, O. M. Bakunin, S. A. Plotnikov, J. H. Lee, S. J. Kim, B. S. Chung, "The use of STM for investigation of surface relief in respect to tribologic properties of DLC coatings," Journal de Physique IV, colloque C5, supplement au Journal de Physique III, V.6, pp. C5-185-C5-188 (1996).

A. E. Davletshin, S. A. Plotnikov, V. B. Vykhodets, I. Sh. Trakhtenberg, V. L. Arbuzov, "The effect of DLC coating on the properties of magnetic audio heads," Journal of Chemical Vapor Deposition, V.4, pp. 113-116 (1995).

I. Sh. Trakhtenberg, S. A. Plotnikov, V. B. Vykhodets, V. A. Pavlov, G. A. Raspopova, "Modification of amorphous diamond-like films by bombardment with low-energy ions," Diamond and Related Materials, V.5, pp. 943-946 (1996).

V. L. Arbuzov, A. B. Vladimirov, V. B. Vykhodets, A. E. Davletshin, S. A. Plotnikov, I. Sh. Trakhtenberg, A. P. Rubshtein, S. D. Gorpinchenko, E. V. Kuzmina, "Practical use of strength and anticorrosion properties of amorphous carbon thin films," Diamond and Related Materials, V. 3, pp. 775-778 (1994).