Adolf Martens

Adolf Martens was a German mechanical and metallurgical engineer who advanced the systematic testing and microscopic study of metals. As a founding figure of German materials-testing institutions, he developed instruments and standardized methods for measuring the strength, hardness and structure of steel and other metals used in engineering, building on Sorby's metallographic techniques to make microstructural analysis a routine industrial practice. The hard, needle-like microstructure that forms when steel is rapidly cooled, martensite, and the associated Martens hardness test are named after him in recognition of his contributions to metallurgical engineering. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/