Abstract: In order to understand the basic physics of wire array Z-pinch more clearly and learn more about the effect of single wire evolution to the wire array imploding, a series of single wire experiments were carried out on 100 kA fast linear transformer driver (FLTD) platform. Varieties of materials such as tungsten, coated tungsten and aluminum were studied in experiments. Two-frame laser shadowgraph and one interferogram were obtained during the evolution of single wire ablation. The results show that the wire core expansion rate of aluminum is faster than that of tungsten with the same initial wire diameter. The aluminum wire core expands uniformly along Z axis during the start of the driver current, while the tungsten wire core has a conical diameter from anode to cathode for polarity effect. The wire core expansion rate of coated tungsten (15 μm W+2 μm Polyimide) is much faster than that of tungsten, even faster than that of aluminum. In addition, wire coating helps reducing the speed of instability development of ablated plasma.