TY - CONF A1 - Griepentrog, Michael T1 - Dynamic instrumented indentation test application and standardisation N2 - The draft of part 5 of ISO 14577 specifies verification and calibration of testing machines for carrying out the measurement of the dynamic material response when an oscillatory force or displacement, with amplitudes small in comparison to the prescribed target values, is imparted to the indenter while the indenter is continuously loaded to a prescribed target load or target depth or while the load or displacement is held constant at a prescribed target value. In case of a material showing plastic-elastic behavior, the measured dynamic response is used for continuous evaluation of the dynamic stiffness of the contact as a function of depth and frequency. Using the dynamic stiffness of the contact a reduced dynamic modulus will be calculated. In case of a material showing visco-elastic behavior from the measured dynamic response also the dynamic contact damping coefficient as function of depth and frequency is evaluated continuously. Using dynamic contact stiffness and dynamic contact damping coefficient reduced lost and storage modulus for visco-elastic materials will be calculated. The main normative requirements of the draft are discussed and their applications are illustrated by examples from daily experimental praxis. T2 - 13th Conference on Local Mechanical Properties CY - Košice, Slovak Republic DA - 06.11.2017 KW - ISO 14577 KW - Instrumented indentation testing KW - Nanoindentation KW - IIT KW - Mechanical properties KW - Dynamic testing KW - Visco-elastic KW - Loss modul KW - Storage modul PY - 2017 AN - OPUS4-43468 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Griepentrog, Michael A1 - Reinstädt, Philipp A1 - Wollschläger, Nicole A1 - Zeigmeister, U. T1 - Size effects in electrodeposited Ni-coatings N2 - Polycrystalline Ni materials with grain sizes less than 100 nm (nano crystalline NC) and with grain sizes in the micrometer range (micro crystalline MC) in form of thin films have become important in many technologies due to their improved physical, chemical and mechanical properties. Usual the mechanical properties of such coatings are described by a Hardness value and a Young´s modulus measured by Instrumented Indentation Testing (IIT).The behavior of such coatings during indentation test is influenced by different size effects having their representative length scale – grain size, coating thickness, length that characterizes the depth dependence of the hardness (Indentation Size Effect ISE). To estimate realistic values for the intrinsic coating Hardness and Young´s modulus all size effects have to be considered. For this work thin nano crystalline Ni – coatings (average grain size 30 nm) with thickness from 1 μm to 5 μm were electrodeposited on brass substrates. Indentation tests in the continuous stiffness measurement (CSM) mode were provided on as prepared Ni – coatings using a G200 Nanoindentation system (Fa. Keysight). For estimation of the intrinsic hardness of the coatings from composite hardness values calculated from the measured force –displacement curve using the Oliver & Pharr method, the model described by Z.S. Ma [1] was used. It was found that the experimental data can be well described by the model. The fitted values for the intrinsic hardness and the fitting parameters will be given. The different values of intrinsic hardness and of length characterizing depth dependence of the hardness for different coating thickness are discussed as results of changes in the coating structure because of changes in deposition parameters. [1] Z.S. Ma, Y.C. Zhou, S.G. Long, C. Lu: On the intrinsic hardness of a metallic film/substrate system: Indentation size and substrate effects. International Journal of Plasticity 34 (2012) 1-11. This work is supported by European Metrology Program for Innovation and Research (EMPIR) (JRP 14IND03 Strength – ABLE) T2 - Conference: Nanomechanical Testing in Materials Research and Development CY - Dubrovnik, Croatia DA - 01.10.2017 KW - Size effect KW - Substrate effect KW - Electrodeposited Ni - coatings KW - Instrumented indentation testing PY - 2017 AN - OPUS4-42664 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -