Technikatörténeti szemle 11. (1979)

TANULMÁNYOK - Petik Ferenc: The development of material testing machines

2. Tensile test on wire in the note-book of Leonardo da Vinci

Requirements for the individual parts can be summarized as follows.

— Clamps should hold the specimen without displacements, whereby the clamping operation should be simple.

— The load generating mechanism is moving one end of the specimen. Today infinitely variable speed is an essential requirement. Speed should be constant independently of changing load or other parameters (such as loading speed, speed of the increase of stress, speed of strain, etc.) should be kept constant.

— The load measuring device should measure loads on the specimen continuously, without time-lag, and it should not influence processes taking place in the specimen.

— The frame contains the complete structure of the machine, it should ensure convenience of handling, and should not influence the behaviour of the specimen during tests.

Pioneers of materials testing

The testing of materials originates at the time when scientists started to systematize empirical knowledge on materials and to complete this knowledge by scientific methods.

The predecessors of material testing machines were actually no machines at all, these were experimental devices employed at examining the basic laws of strength of materials.

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