Accession Number : AD0473942

Title :   DEVELOPMENT OF IMPROVED CUTTING TOOL MATERIALS.

Descriptive Note : Final rept. 1 Nov 62-15 May 65,

Corporate Author : CARBORUNDUM CO NIAGARA FALLS NY

Personal Author(s) : Whitney, E. Dow ; Murata, Yorihiro ; Julien, H. Paul ; Niesse, John E. ; Crayton, Philip H.

Report Date : OCT 1965

Pagination or Media Count : 462

Abstract : New and improved ceramic cutting tools for the machining of AISI 4340 and D6AC steels were developed. The new tools showed a substantial improvement over commercially available Co-bonded WC and Al2O3 based tools in the machining of the above metals. These new tools resulted from screening and fabrication studies on 9 refractory materials. The tool fabricated from the initial composition 60 Wt% TaN - 40 Wt% ZrB2 by hot pressing under suitable conditions proved to be superior to all commercially available tools tested during this program. Other ceramic systems which exhibited promise for the fabrication of tools for the machining of AISI 4340 and D6AC steels were: 50 Wt% TaN - 50 Wt% TiB2, and 50 Wt% TiB2 - 50 Wt% TaC. A machinability parameter study was initiated and in several cases these parameters could be qualitatively correlated with the cutting test performance of conventional carbide and ceramic tools. Ultrahigh pressure, high temperature experiments resulted in the synthesis of LiSi2N3 and MgSiN2. These compounds hold promise as additives for the densification of Si3N4. (Author)

Descriptors :   *CERAMIC MATERIALS), (*CUTTING TOOLS, (*REFRACTORY MATERIALS, CUTTING TOOLS), STEEL, MACHINING, TANTALUM COMPOUNDS, TITANIUM COMPOUNDS, LITHIUM COMPOUNDS, SILICON COMPOUNDS, NITRIDES, BORIDES, CARBIDES, ZIRCONIUM COMPOUNDS, MAGNESIUM COMPOUNDS, ADDITIVES, PHASE STUDIES, SYNTHESIS(CHEMISTRY), MANUFACTURING, MECHANICAL PROPERTIES, DENSITY, MICROSTRUCTURE, PROCESSING.

Distribution Statement : APPROVED FOR PUBLIC RELEASE