Source: BAM

Adolf Martens: a pioneer of materials engineering and failure analysis, designer of testing machines and head of the Royal Mechanical-Technical Testing Institute, from which today’s BAM later emerged. He was a personality who established principles for the procedure of failure analysis – procedures still valid today.

The name Adolf Martens is alive in the international community of material scientists and engineers. A metallographic constituent is called martensite in his honour. Martensite occurs in many steels submitted to rapid quenching and significantly increases their hardness. 17 selected failure investigations, well known to the public, performed by BAM and its predecessor institutions have now been published in a special issue of the "Engineering Failure Analysis" journal on the 100th anniversary of Martens’ death. A team of 25 BAM authors have scientifically analysed these failure cases.

The special issue begins with a review of original studies by Martens from 1896. Martens worked on numerous methods of materials testing such as macro photography, fractography, metallography and hardness measurement, and he improved them significantly. Methods of materials testing and failure analysis have continuously been improved and new methods of chemical analysis and non-destructive testing have been added. However, the approach of failure analysis has since changed little: thorough on-site assessment, extensive initial visual non-destructive investigation, basic understanding of the operation and operating history, materials testing and load analysis as well as establishing a consistent hypothesis about the causes and processes of failure.

A paper reports about the failures at the Berlin Freedom Bell, a gift of the "National American Committee for a Free Europe". In 1966, the main bolt of the clapper broke and fell five metres deep onto the underlying floor. The partial collapse of the unusually shaped reinforced concrete roof of the Berlin Congress Hall in 1980 – also a gift of the Americans – is also scientifically discussed in another paper.

In this special issue, BAM scientists have for the first time published their results about the failure analysis of two samples from the bow ramp of the Baltic ferry MV ESTONIA which sank 20 years ago on 28 September 1994. BAM received the samples in October 2000. Divers had taken them by flame cutting from the wreck which still lies 60 metres deep on the bottom of the Baltic Sea. Since the ship had then been in sea water for six years, the metal surface of the samples was no longer suitable for failure analysis. Therefore, on the BAM Test Site ‘Technical Safety’ ((Link setzen)), the experts conducted comparative tests on sheets similar to those used by the shipyard to build the ESTONIA in 1979-1980. A number of studies have led to the conclusion that the deformation changes in the microstructure of the samples were not caused by a suspected explosion, but by the usual pre-treatment of the metal surfaces by shot peening for the subsequent application of a coat of paint.