TY - JOUR A1 - Kiehl, Maximilian A1 - Scheid, Adriano A1 - Graf, Karin A1 - Ernst, Benedikt A1 - Tetzlaff, Ulrich T1 - Coaxial Laser Cladding of Cobalt-Base Alloy Stellite™ 6 on Grey Cast Iron Analysis of the Microstructural and Mechanical Properties Depending on the Laser Power JF - Journal of Materials Engineering and Performance N2 - A high-power diode laser was used to generate single- and multi-bead coatings of Stellite™ 6 by coaxial laser cladding over flat grey cast iron (EN-GJLP-200) as a preliminary study to develop a wear and corrosion resistant coating for brake disks on a cost-effective substrate. In this article, we have focused on a detailed quantitative analysis of the effect of different laser powers (1.5, 2.0, 2.5, 3.0, 3.5, and 4.0 kW) on the bead geometry, dilution, microstructure, and hardness. Coatings dilution or composition depends directly on the laser power as well as bead geometry. The typical microstructure of the coatings comprises a solid solution of α (hcp)- and β (fcc)-Co with a dendritic structure as a metal matrix and an interdendritic lamellar eutectic, which contains predominantly β-Co, chromium carbides Cr7C3 and Cr23C6 as well as blocky tungsten carbide W2C. Coating hardness depends on the chemical composition and microstructure that is modified by the deposition parameters. Low laser power results in high carbide fraction and most refined microstructures, accounting for harder coatings. UR - https://doi.org/10.1007/s11665-022-07358-3 KW - bead geometry KW - grey cast iron KW - hardness KW - laser power KW - microstructure KW - Stellite 6™ Y1 - 2022 UR - https://doi.org/10.1007/s11665-022-07358-3 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-31249 SN - 1544-1024 SN - 1059-9495 VL - 32 IS - 8 SP - 3821 EP - 3838 PB - Springer CY - New York ER - TY - JOUR A1 - Kiehl, Maximilian A1 - Scheid, Adriano A1 - Graf, Karin A1 - Ernst, Benedikt A1 - Tetzlaff, Ulrich T1 - Coaxial laser cladding of cobalt-base alloy Stellite™ 6 on gray cast iron/investigations on friction, wear versus commercial brake pad, and corrosion characteristics JF - Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering UR - https://doi.org/10.1177/09544070221145512 Y1 - 2023 UR - https://doi.org/10.1177/09544070221145512 SN - 2041-2991 SN - 0954-4070 VL - 237 IS - 14 SP - 3285 EP - 3303 PB - Sage CY - London ER - TY - JOUR A1 - Ernst, Benedikt A1 - Keim, Simon A1 - Tetzlaff, Ulrich T1 - On the anisotropic indentation modulus and anisotropic creep behavior of β-Sn characterized by nanoindentation methods JF - Materials Science and Engineering: A UR - https://doi.org/10.1016/j.msea.2022.143392 Y1 - 2022 UR - https://doi.org/10.1016/j.msea.2022.143392 SN - 1873-4936 SN - 0921-5093 VL - 2022 IS - 848 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Ernst, Benedikt A1 - Kubaschinski, Paul A1 - Schiessl, Andreas A1 - Waltz, Manuela A1 - Höppel, Heinz Werner A1 - Tetzlaff, Ulrich T1 - Comparison of the Young’s modulus of the lead free solder alloy Sn-Ag3.8-Cu0.7 determined by hot tensile tests, ultrasonic measurements and 𝛽-Sn single crystal calculations JF - Materials Science and Engineering: A N2 - Sn-based solders are known for their tendency to form coarse grained microstructures. In combination with the high elastic anisotropy of 𝛽-Sn, the overall elastic properties and their interpretation require a careful discussion of the structure–property-relationship as elastic constants are often important input parameters for creep or fatigue models. This study therefore investigates the influence of microstructure and testing method on the Young’s modulus E for the widespread lead free solder alloy Sn-Ag3.8-Cu0.7 (SAC387) using bulk specimens. Due to its already high homologous temperature at room temperature (Thom ≈ 0.6 = T/Tm for Tm being the melting temperature), hot tensile tests generally bear the risk of superimposed creep deformation. Mechanical testing becomes even more challenging, since yield strengths are usually low for these alloys. Consequently, in addition to the hot tensile tests executed for the engineering strain rate 𝜖̇𝑒 = 1 ⋅ 10−3 s−1, two supplemental methods are used to determine the Young’s modulus comprising of the dynamic resonance frequency measurement and the calculation of the Young’s modulus based on single crystal compliance data of the majority phase 𝛽-Sn.Young’s moduli yielded from dynamic resonance frequency measurement and calculations based on single crystal compliance data showed comparable results of (E35 ◦C ≈ 55 GPa, E80 ◦C ≈ 51 GPa and E125 ◦C ≈ 48 GPa). Hot tensile tests showed similar data with the largest deviation at 80 ◦C, where E80 ◦C ≈ 53 GPa was determined. These absolute values and their temperature dependence can be attributed to the microstructure of the cast specimens which show a general preferred orientation of 𝛽-Sn grains close to <110> after analysis via electron backscattered diffraction (EBSD). A comparison with literature data revealed significant differences in the Young’s moduli which are likely to be attributed to differences in the preferred orientation of 𝛽-Sn grains. UR - https://doi.org/10.1016/j.msea.2024.147354 Y1 - 2024 UR - https://doi.org/10.1016/j.msea.2024.147354 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-52143 SN - 1873-4936 SN - 0921-5093 VL - 2024 IS - 916 PB - Elsevier CY - Amsterdam ER -