Strength of Iron Melt at High Extension Rate During Femtosecond Laser Ablation

Time and spatial-resolved interferometric technique in a picosecond range was used for continuous registration of motion of iron target surface heated by femtosecond laser pulse. The magnitude of the tensile stress 0.5-1.3 GPa leading to fracture of molten iron at the strain rate of similar to 10(9) s(-1) was experimentally determined from the measured velocity histories of the spalled layer movement.