Study on Enhancement of Mechanical Strength by Knotted Shape Memory Alloy Fiber in TiNi Fiber Composites

In this paper, the experimental investigation into the enhancement of mechanical strength in shape memory alloy (SMA) fiber composites is made by using knotted fiber at the two ends instead of straight fiber. TiNi SMA fiber with both ends knotted is used for purpose of better ensuring stress transfer from the matrix to the fiber than straight fiber. Tension test is carried out above the austenitic finish temperature in air. Specimens are heated by means of electrical resistive lamplight heating. The results indicate that the mechanical strength is larger in the knotted fiber composite than in the straight fiber composite. Knotted fiber exerts the superiority of TiNi SMA fiber composite.