IDEA #4C8EN7 Nanomceramic Composites For Wearmresistive Applications

NEW(cid:3)MATERIALS(cid:3)AND(cid:3)NANOTECHNOLOGY NANOMCERAMIC COMPOSITES FOR WEARMRESISTIVE APPLICATIONS Description We present technologies for development of ceramic nano$ composites based on SiC$C and Si3N4$TiN$TiB2 systems for using in novel generation of ceramic cutting tools, wear resistive components, radiation resistive ceramic compo$ nents and for other potential applications. Such properties as high melting temperatures, hardness, chemical and ther$ mal stability and other are successfully combined in them. Formula SiC$C means nanocrystalline (40–120 nm) beta$ silicon carbide reinforced with diamond planar clusters built$into the lattice of SiC. This unique structural proper$ ty provides for 40 GPa hardness in pure poreless ceramics. We found hardness of 24 GPa in nanocompostes with alumi$ na, which also show fracture toughness around 9 MPa m1/2. As a result of NATO SfP project we have built the pilot unit for production of 20 kg of SiC$C nanopowder a day. Here we propose the technology development of the nano$ composites based on SiC$C nanopowders. Another group of nanocomposites based on nano$TiN reinforced with nano TiB2 and Si3N4 particles was obtained by sintering, high$pressure sintering and spark$plasma sin$ tering. Prototypes of cutting tools (unresharpable tools) were tested both at room and elevated temperatures. These composites are promising tools for extra$fine finishing of metallic parts. Such parameters as hardness around 20 GPs, fracture toughness up to 8.5 MPa m1/2, show high stability (grain size around 80 nm) up to 800 C which looks attrac$ tive. The best combination of properties: hardness 24 GPa, bend strength > 500 MPa, and fracture toughness of 7 MPa m1/2 was revealed for the TiN$25 %Si3N4 nanocom$ posite. With sintering process without pressure near fully dense (98.5 %) ceramics can be achieved and therefore, such process is promising for mass production of tools. At present we propose development of technology for ceramic cutting tools based on TiN$Si3N4 ceramic nanocomposites. Innovative Aspect and Main Advantages A very good combination of hardness and fracture tough$ ness at room and elevated temperatures looks attractive for cutting tool application. Technological operations are not expensive: for instan$ ce, synthesis of SiC$C is comparable with analogues by costs, pressureless sintering at moderate temperatures is used instead of hot pressing etc. Refinement of grains is a desirable property for fin$ ishing treatment of alloyed steels and viscous metals and alloys. Stability of properties at high temperatures is prom$ ising for dry cutting operations. We have a patent of Russian Federation concerning technology of SiC$C nanopowder synthesis, pending patents of Ukraine and know$how in technologies of TiN$TiB2 and TiN$Si3N4 nanocomposites. Areas of Application Cutting tools, ceramic bearings, wear resistive components. Cutting tools made from Si3N4$TiN nanoceramics were tested in ALCON (Kiev, Ukraine). Wear resistive com$ 46 Fig. 1. SiCMC nanopowders Fig. 2. TiNMSi3N4 multilayer cutting plates (50 % Si3N4 50 % TiN) ponents based on SiC$C ceramics were examined in Baker Hughes INTEQ GmbH. Stage of Development The pilot unit for SiC$C nanopowder synthesis is under ope$ ration. The pilot batch of cutting tools made from Si3N4$TiN nanoceramics has been prepared. Technical documentation is under preparation. We have a patent of Russian Federation concerning te$ chnology of SiC$C nanopowder synthesis, pending patents of Ukraine and know$how in technologies of TiN$TiB2 and TiN$Si3N4 nanocomposites. We would prefer joint development of ceramic nano$ composite products with foreign partner. Licensing of te$ chnologies or development of start$up company or joint venture would be also appropriate. Contact Details Frantsevich Institute for Problems in Materials Science 3, Krzhizhanovski str. Nanostructured Materials and Nanocomposites Nanocomposites based on high melting compounds Andrey V. Ragulya, Dr. Prof. Vice$director of IPMS Tel.: (including code) +38$044$424$7435 Fax: (including code) +38$044$424$2131 Ragulya@ipms.kiev.ua SCIENCE AND INNOVATION. № 4, 2006