Process Quality in Rapid Manufacturing

Abstract

The subject of this presentation is the qualification of a rapid manufacturing process in terms of the created product. The analysis was based on using a high power CO2 laser as energy source for parts creation, material under investigation is Stainless Steel SS304. The incident CO2 laser beam power was varied from 300 W to 400 W, with the laser beam showing a Gaussian intensity distribution. The laser beam was focused to a focal diameter of 460 μm using a 127 mm (5“) focal length lens. This study investigates, for a variety of operating conditions, the smoothness of the material deposition, the process’ inherent susceptibility to lateral misalignment, geometrical characteristics of the process, and the permissible yield and ultimate tensile strengths. The yield strength is close to isotropic (250 MPa, same as wrought SS304), despite the expectation that the joints between the layers would turn out as the weakest link in the chain, and height deviations were well within 10% of the deposition height for high powers and small substrate translation speeds. The impact of a lateral misalignment is comparable to values for other laser materials processing situations.