Effect of SiC Addition to Al2O3 Ceramics Used in Cutting Tools

Abstract

In this study, the effect of the addition of silicon carbide to alumina ceramics commonly used in cutting tool applications is addressed. Performance of Al2O3–SiC composite cutting inserts during the machining of hardened steels and ductile iron was compared to the results obtained for a cutting tool made out of 99 wt.% Al2O3, Al2O3–TiC, Al2O3–TiC–ZrO2, and Al2O3–TiN. In almost all tests, the composite with silicon carbide demonstrated better wear resistance, longer tool lifetime, and the ability to cut at higher speeds. The enhanced properties of cutting tools with SiC can be attributed to the morphology and dimensions of the inclusions in the matrix as well as to the strength of the interphase boundaries, small porosity, and lack of high inner stresses in the volume.

Advances in Electrical Discharge Machining of Insulating Ceramics

“…The value of specific electrical resistance for produced conductive ceramic with 30 vol.% of TiC is close to the value for carbon in the form of graphite (ρ = 8 × 10 −6 Ω•m) [28]. Thus, the samples of sintered Al 2 O 3 + TiC ceramic with more than 30 vol.% of TiC are suitable for electrical discharge machining [25][26][27]. The electrical conductivity of some conductors can fluctuate in the range of 10-10 −12 S/m (ρ = 10 −1 -10 12 Ω•m) and also depends on many factors, including temperature and crystal lattice orientation (some materials, such as carbon, exhibit anisotropy of electrical properties) [29][30][31].…”

“…Solving the problems of electrical discharge machining application techniques for aluminum-containing ceramics is of fundamental importance for science and applications such as electric power, the space industry, optics, and a promising cutting tool made of cutting ceramics. The development of superhard and highly wear-and heat-resistant materials based on ceramics with A low coefficient of linear thermal expansion (α × 10 6 of 7.0-8.0 K −1 for Al 2 O 3 , 4.0-6.0 K −1 for AlN, 3.0 K −1 for SiAlON at 20-1000 • C); Low thermal conductivity at normal temperatures (λ of [22][23][24][25]…”

Analysis of the Electroconsolidation Process of Fine-Dispersed Structures Out of Hot Pressed Al2O3–WC Nanopowders

“…It should be noted, however, that electroconsolidation at the lowest heating rate of 50 • C/min provided grain dimensions between 6 and 9 µm, while with the commercially available BO-13 cutting tool, and material obtained through the sintering method, Al 2 O 3 grain size is ca. 2-5 µm [45].…”

Special features of manufacturing cutting inserts from nanocomposite material Al2O3-SiC

“…5. As15-6 is a composite material obtained in the course of work [24]. The basis is microdispersed aluminum oxide with the addition of 15 %wt.…”