A Newly Designed Dynamic Fatigue Testing Machine for Plastics

Abstract

A new fatigue testing machine of constant load type has been designed for the purpose of investigating the dynamic fatigue which is characteristic of plastic materials, because the plastics reinforced by glass fiber (so-called FRP) is practically used for structural members inplace of metals. Fig. 1 shows the general view of this machine which has the capacity of 1000kg and several merits described as follows.(1) Regardless the change in the rigidity of the test piece during the fatigue test, the dynamic load that acts on the test piece is still kept constant.(2) Three testing speeds can be selected. (3) Variation of the dynamic load and the testing speed is negligibly small. As the result of many fundamental tests it is confirmed that the machine operates as has previously been expected.(Received Jan. 21, 1967)