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Cutting Operations (cutting + operations)

Distribution by Scientific Domains

Polymers and Materials Science	83%

Selected Abstracts

Thermal Investigation of Al2O3 Thin Films for Application in Cutting Operations,

ADVANCED ENGINEERING MATERIALS, Issue 7 2009
Kirsten Bobzin
Crystalline PVD ,-Al2O3 coatings offer great potential for use in high-speed cutting operations. They offer specific high temperature features, like high hot hardness and high oxidation resistance. However, the reasons for the high thermal stability of this system are not clearly understood. In this paper, the phase and oxidation stability of thin ,-Al2O3 films (as illustrated in the micrograph) are investigated. [source]

Pulsed Nanocomposite TiAlN Coatings on Complex Shaped Tools for High Performance Cutting Operations

PLASMA PROCESSES AND POLYMERS, Issue S1 2007
Kirsten Bobzin
Abstract The demand on high profitability in cutting operations has led to a variety of requirements for high performance tool coatings. Nanostructured coatings have shown most promising results in this connection. High oxidation resistance, hot hardness, and loW friction are just a few benefits that these coatings offer. The deposition of nanostructured coatings is only possible within a small deposition process window. Most cutting tool surfaces are complex shaped and include, for instance, small corner radii at the cutting edge or chip breakers. The local process window and the deposition parameters must be adapted to the actual shape of the cutting tools in order to obtain a hard nanocomposite coating with adequate adhesion properties. Finally, the performance of these coatings has been studied in machining tests. [source]

Crystalline , -Alumina Deposited in an Industrial Coating Unit for Demanding Turning Operations,

ADVANCED ENGINEERING MATERIALS, Issue 1-2 2010
Kirsten Bobzin
Crystalline PVD ,-Al2O3 - coatings offer great potential for their use in high-speed cutting operations. They promise high hot hardness and high oxidation resistance at elevated temperatures. This is important for coatings that are used for machining of materials with low thermal conductivity such as stainless steel or Inconel 718 because heat generated during cutting can barely be dissipated by the chip. Because of the prevailing bonding forces of alumina, adhesion-related sticking can be reduced even for dry cutting. Furthermore, the high formation enthalpy of alumina prevents chemical reactions with frictional partners. The present work gives an overview of the deposition of ,-Al2O3 thin films on WC/Co-cutting inserts by using pulsed MSIP (magnetron sputter ion plating) PVD technology. To improve adhesion, a (Ti,Al)N bond coat was employed. The samples were analyzed using common thin film test equipment. Cutting tests and pin-on-disk examinations were carried out to test the coating's performance. For turning operations, the difficult-to-machine austenitic steel 1.4301 (X5CrNi18-10) was used. In comparison to a state-of-the-art (Ti,Al)N coating, (Ti,Al)N/,-Al2O3 showed a longer tool life. [source]

Thermal Investigation of Al2O3 Thin Films for Application in Cutting Operations,

Barrier and mechanical properties of injection molded montmorillonite/polyesteramide nanocomposites

POLYMER ENGINEERING & SCIENCE, Issue 1 2005
M. Krook
Properties of injection-molded biodegradable polyesteramide composites containing 5 and 13 wt% octadecylammonium-treated montmorillonite clay have been studied. Oxygen transmission rates and mechanical properties were measured. X-ray diffraction was used to assess the degree of intercalation of the clay layer stacks, and transmission electron microscopy (TEM) was used to assess the morphology and degree of layer delamination. A substantial reduction in oxygen permeability was observed when clay was added to the composites. The oxygen permeability of the 13 wt% clay sample was only 20% of that of the pure polymer. The in-plane stiffness and in-plane strength of the sheets were greatly improved without any embrittlement. These beneficial effects were probably due to the high degree of clay layer exfoliation and orientation observed by TEM. Heat shrinkage, toughness analysis, and cutting operations suggested that the polymer chains and the clay layers were oriented parallel to the plane of the sheet. TEM and X-ray showed that stacked layers were still present but that these were significantly intercalated. The clay-layer periodic spacing increased from 25 Å to approximately 35 Å during processing. POLYM. ENG. SCI. 45:135,141, 2005. © 2004 Society of Plastics Engineers [source]

Synthesis of ultrafine titanium carbonitride powders,

APPLIED ORGANOMETALLIC CHEMISTRY, Issue 5 2001
Frederic Monteverde
Abstract Titanium-carbonitride-based materials are very hard materials with increasing technical importance. They are mainly used in composites with various metal carbides and/or metallic binders (cermets) for metal cutting operations. These applications call for the synthesis of titanium carbonitride powders with homogeneous chemical composition, as small as possible grain size and narrower grain size distribution. Nowadays on the market, only commercial submicrometric (0.5,2,,m) powders are available. Starting from blends of nanosize commercial TiN or TiO2 powders mixed with different carbon powders (carbon black, active carbon), this study aimed to set up a low-cost process to synthesize fine and pure TiC1,X,NX powders with an X value close to 0.5. The morphology of the as-obtained powders and the progress of the reaction were investigated by scanning electron microscopy and X-ray diffraction. The stoichiometric parameter X was estimated on the basis of a TiC1,X,NX Raoultian solid solution together with Vegard's rule. The results are presented and discussed to assess relations between powder characteristics and processing conditions. The most encouraging results were obtained using a mixture TiN,+,10,wt%C (carbon black) processed at 1430,°C for 3,h under flowing argon. Regularly shaped particles with limited agglomeration ranged from 100 to 300,nm and an X value close to 0.5 Copyright © 2001 John Wiley & Sons, Ltd. [source]