TY - JOUR A1 - Bettge, Dirk A1 - Azevedo, César Roberto de Farias A1 - Klinger, Christian T1 - Editorial - Special Issue “A Tribute to A. Martens” N2 - The 100th anniversary of the death of Adolf Martens will be commemorated on July 24th, 2014. He is eponymously remembered today through the term martensite, which was first used by Floris Osmond as a name for the metastable phase that results from rapid quenching of carbon steels. Born in 1850 near to Hagenow in the region Mecklenburg, Germany, Martens was one of the pioneers of materials engineering in 19th century Europe. Martens began his career working for the Prussian Eastern Railway before joining the Royal Industrial Academy in Berlin in 1880. In 1884, he was appointed director of the Royal Mechanical Experimental Station, a small institution associated to the academy. Failure analysis was continuously practiced at this institution, which became later the nucleus of the German Federal Institute for Materials Research and Testing (BAM), for the 110 years since. The history of Martens will be dealt with in an in-depth article in this special issue. Since the 19th century, failure analysis techniques have been refined, and new methods of chemical analysis and non-destructive testing have been developed; however, the basic approach to failure analysis has not changed much since Martens' days. The basic tenets of failure analysis remain things like on-site inspection, extensive visual 'non-destructive' inspection, developing an understanding of the background story, performing materials testing, and 'connecting the dots.' Martens introduced and developed experimental techniques like macro photography, fractography, metallography, hardness measurements, and mechanical testing. Modern failure analysts continue adding even more techniques to this list, leading to a more interdisciplinary approach – which many would say is the only way to find the root causes of complex failure events. The present special issue of EFA presents an overview of more than 100 years of failure analysis at BAM and its predecessors, closing the circle from the beginnings of modern failure analysis done by Martens himself in the 1890s to its present-day application. This special issue starts with an excursion back to Martens' work and innovations and presents a newly translated original manuscript of Martens from 1890. Whereas some papers of Martens and his co-workers are well documented, only little can be found about failure analysis in the period from 1914 to the 1950s. Most documents of this period have not survived until today. Beginning in the 1960s more and more significant works are preserved, which were using the interdisciplinary approach of Martens. Since the beginning of the digital age in the 1980s almost all text documents are accessible, whereas digital images were stored since the 1990s. Since then the problem is no longer accessibility but copyright issues that prevent many interesting case studies from being published. Maybe the next generation of failure scientists can reveal some of them later on. PY - 2014 U6 - https://doi.org/10.1016/j.engfailanal.2014.04.006 SN - 1350-6307 SN - 1873-1961 VL - 43 IS - Special Issue 'A Tribute to A. Martens' SP - 1 PB - Elsevier Science Publ. CY - Oxford AN - OPUS4-31591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rodrigues, A.C.P. A1 - Österle, Werner A1 - Gradt, Thomas A1 - Azevedo, César Roberto de Farias T1 - Impact of copper nanoparticles on tribofilm formation determined by pin-on-disc tests with powder supply: Addition of artificial third body consisting of Fe3O4, Cu and graphite N2 - Copper, magnetite and graphite particles were mixed in order to observe their impact on the coefficient of friction (CoF) during pin-on-disc tests and on the tribofilm formation after testing. Pure magnetite powder provided a value of CoF of 0.4. Magnetite-copper mixtures tested at 400 °C revealed lower CoF values (~0.4) than those at room temperature (~0.6). Magnetite-graphite and magnetite-graphite-copper mixtures presented lower CoF values (~0.3). All systems formed a magnetite-based tribofilm and patches of metallic copper were found on the tribosurfaces of the mixtures containing copper. Carbon layers and graphite nanoinclusions were observed in the graphite mixtures. The incorporation of zirconia particles, a by-product of ball milling mixing, prevented the selective transfer of graphite and copper to the tribosurfaces of some of the samples. KW - Brake pad materials KW - Sliding friction KW - Transfer layer KW - Surface analysis KW - Model friction tests PY - 2017 U6 - https://doi.org/10.1016/j.triboint.2017.02.014 SN - 0301-679X VL - 110 SP - 103 EP - 112 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-40104 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -