Analysis of a flexural wave due to a laser heating pulse: The two-layer assembly case

Abstract

Abstract

In the present study laser ablation of a two-layer assembly with a cantilever arrangement is considered. The recoil pressure generated at the vapour front-workpiece interface is formulated and the resulting pressure force (loading force) is computed. The flexural motion of the workpiece due to the loading force is formulated. The first layer of the workpiece is Inconel 625 with a thickness on the order of 200 μm, which may resemble the HVOF (high-velocity oxygen fuel) coating, while the second layer is 1 mm thick stainless steel plate. The simulations are repeated for four values of the first layer thickness and the relation between the magnitude of the displacement and the first layer thickness is discussed. It is found that the displacement of the workpiece reaches as high as 2 μm in the region close to the free end, while the equivalent stress level is high in the region close to the fixed end. The temporal behaviour of the equivalent stress almost follows the displacement behaviour of the workpiece. As the first layer thickness increases, the displacement reduces. The variation of displacement with the first layer thickness is almost linear and the slope of this variation attains high values for certain time periods in the flexural motion.