TY - JOUR A1 - Dörfel, Ilona A1 - Wäsche, Rolf A1 - Rabe, Torsten A1 - Steinborn, Gabriele T1 - Tribological Induced Microstructural Changes in Subsurface Layers of Si3N4-Based Materials KW - Tribologie PY - 1994 SN - 1013-9826 VL - 89-91 SP - 763 EP - 767 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-577 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Klaffke, Dieter T1 - Wear of multiphase SiC based ceramic composites containing free carbon N2 - Ceramics are of increasing interest for application in many branches of technique. In order to improve the tribological performance of ceramic materials, composites on the basis of silicon carbide with different amounts of titanium carbide, boron carbide, titanium diboride and free carbon in the form of graphite were manufactured by a reaction sintering process. The friction and wear behaviour of these composites was investigated with oscillating sliding motion in unlubricated tests at room temperature on different levels of relative humidity. Additional tests were performed under water lubrication, revealing the superior behaviour of composites for special test conditions. A major influence of the free carbon on friction or wear behaviour was not observed. The tribological behaviour in air as well as under water is mainly dependant on the amount of titanium phases. KW - Siliziumkarbid KW - Verbundwerkstoffe KW - Tribooxidation KW - Silicon carbide KW - Ceramic composites KW - Humidity water KW - Lubrication PY - 2001 U6 - https://doi.org/10.1016/S0043-1648(01)00566-X SN - 0043-1648 VL - 249 SP - 220 EP - 228 PB - Elsevier CY - Amsterdam AN - OPUS4-900 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Naito, M. A1 - Jahanmir, S. T1 - TWA 27 Characterization Methods for Ceramic Powders and Green Bodies KW - Standardisierung KW - Keramische Pulver KW - Grünkörper PY - 2000 SN - 1016-2178 IS - 23 SP - 21 EP - 27 PB - National Institute of Standards and Technology AN - OPUS4-979 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rudolph, Pascale A1 - Brzezinka, Klaus-Werner A1 - Wäsche, Rolf A1 - Kautek, Wolfgang T1 - Physical chemistry of the femtosecond and nanosecond laser-material interaction with SiC and a SiC-TiC-TiB2 composite ceramic compound N2 - The interaction of nanosecond laser pulses in the ultraviolet wavelength range and femtosecond laser pulses in the near-infrared region with the semiconductor SiC and the composite compound SiC–TiC–TiB2 was investigated. Surface analytical techniques, such as XPS, depth profile (DP), and micro-Raman spectroscopy (?-RS) were used to identify the chemical changes between untreated and laser-treated areas. Single-pulse irradiation led to material modifications in the condensed state in most instances. Multi-pulse results differed depending on the pulse duration. Crystal structure changes were observed as a consequence of laser-induced melting and resolidification. In air contact all components underwent oxidation reactions according to thermodynamic expectations. Exceptions were observed under exclusion of oxygen, SiC was reduced to elemental Si. KW - Femtosecond techniques KW - Nanosecond techniques KW - Ceramics KW - Raman spectra/condensed matter KW - XPS/surface analysis PY - 2003 U6 - https://doi.org/10.1016/S0169-4332(02)01356-9 SN - 0169-4332 SN - 1873-5584 VL - 208-209 SP - 285 EP - 291 PB - North-Holland CY - Amsterdam AN - OPUS4-2791 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf T1 - Feste Schmierstoffe für hohe Temperaturen - Eine Literaturübersicht PY - 1989 SN - 0724-3472 VL - 36 IS - 3 SP - 145 EP - 151 PB - Expert Verlag CY - Renningen AN - OPUS4-1432 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Steinborn, Gabriele T1 - Characterisation of the secondary properties of alumina - measuring the isoelectric point by a streaming potential method PY - 1997 SN - 0173-9913 SN - 0196-6219 VL - 74 IS - 5 SP - 235 EP - 239 PB - Göller CY - Baden-Baden AN - OPUS4-1434 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Steinborn, Gabriele T1 - Influence of Slip Viscosity on the Mechanical Properties of High Purity Alumina made by Gelcasting KW - High purity alumina KW - Gelcasting KW - Solid content KW - Viscosity KW - Deairing KW - Bending strenght KW - Microstructure KW - Computertomography KW - Defect type PY - 1997 SN - 1013-9826 VL - 132 SP - 374 EP - 377 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-1435 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Abe, H. A1 - Naito, M. A1 - Hackley, V. A1 - Hotta, Y. T1 - Influence of particle size and solid loading on the determination of the isoelectric point (IEP) of ceramics powders by different methods N2 - The isoelectric point is a material property for the characterization of acid-base behavior of the powder surface. The IEP of two alumina powders (AKP-30, Grade A) with different particle size characteristics in aqueous suspension has been determined by colloid vibration current (CVI) and particle charge detection (PCD) methods in moderately concentrated suspensions in order to qualify these methods for a future standardization. The solid loading of the suspensions were 1 and 5 vol%. The comparison of the IEP determined by PCD and CVI was in good agreement. However, the solid loading dependence of IEP and a large IEP hysteresis (at 1 vol%) were observed, which do not allow a proper determination of the IEP. The recording of the potential curve and therfore the determination of the IEP with CVI was difficult for the suspension of Grade A powder due to formation of agglomerates at pH values near the pHIEP. T2 - 7th Euro Ceramics - Conference and Exhibition of the European Ceramic Society (ECerS) CY - Brugge, Belgium DA - 2001-09-09 KW - Isoelectric point (IEP) KW - Alumina powder KW - Particle charge detection (PCD) KW - Colloid vibration current (CVI) PY - 2002 UR - http://ois.nist.gov/nistpubs/technipubs/recent/search.cfm?dbibid=9289 U6 - https://doi.org/10.4028/www.scientific.net/KEM.206-213.3 SN - 1013-9826 VL - 206-213 SP - 3 EP - 6 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-1437 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Klaffke, Dieter T1 - Ceramic particulate composites in the system SiC-TiC-TiB2 sliding against SiC and Al2O3 under water N2 - The tribological behaviour of SiC, SiC-TiC and SiC-TiC-TiB2 was determined in oscillating sliding against SiC and -Al2O3 in water at room temperature. The tribo-systems with the composite materials containing TiC and TiB2 differ significantly from the systems with the single phase SiC: The wear is reduced and the friction is increased. The wear reduction up to a factor of 10 is mainly due to the formation of an oxide film containing titanium oxides which is soft, stable in water and well adhering to the bulk material. This oxide film is transferred to the alumina ball but not to the silicon carbide ball. KW - Silicon carbide KW - Titanium carbide KW - Titanium boride KW - Ceramic KW - Particulate composites KW - Oscillating sliding KW - Water lubrication KW - Friction KW - Wear PY - 1999 U6 - https://doi.org/10.1016/S0301-679X(99)00033-X SN - 0301-679X VL - 32 IS - 4 SP - 197 EP - 206 PB - Butterworth-Heinemann CY - Oxford AN - OPUS4-1440 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klaffke, Dieter A1 - Wäsche, Rolf A1 - Yarim, Rasim T1 - Tribological Behaviour of SiC-TiC-TiB2 Composites under Unlubricated Sliding Conditions KW - Silicon carbide KW - Titanium carbide KW - Titanium diboride KW - Alumina KW - Oscillating sliding KW - Relative humidity PY - 2003 SN - 1354-4063 SN - 1557-685X VL - 9-3 IS - 9 SP - 185 EP - 195 PB - Coppin CY - Deal AN - OPUS4-2486 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -