Advances in Ultrasonic Testing of Cementitious Materials - Paper describes an ultrasonic device which is able to extract certain parameters of ultrasonic waves recorded continuously during the setting and hardening of mortar. [465 kB] - http://www.iwb.uni-stuttgart.de/grosse/papers/Festschrift2.pdf
Hardness Testing - Guide to hardness testing of materials. Brinell, Vickers and Rockwell test methods are illustrated, along with hardness conversion tables and charts. - http://www.gordonengland.co.uk/hardness/
Materials Expertise for the Gas Industry - Information about testing of butt welds, condensate, and materials used by gas industry (sinter metals, catalytic burners). - http://www.xs4all.nl/~flscholt/