Investigation of the Mechanical Properties on Hybrid Deposition and Micro-Rolling of Bainite Steel
Wire and arc additive manufacturing (WAAM) is a novel technology with high efficiency and low cost for mass popularity. Whereas, the lack of deposition accuracy and microstructure performances are still restricting its ongoing development. In this paper, hybrid deposition and micro-rolling (HDMR) process has been used to eliminate the anisotropy in WAAM bainitic steel samples. For the problems of deficient deformation and larger remelting area due to deeper penetration and higher temperature gradient, an initially optimized micro-rolling morphology has been proposed. The results show: the tensile strengths of finished part are 1275MPa, 1256MPa, 1309MPa for transverse (X), longitudinal (Y), perpendicular (Z) directions respectively. The elongation of three directions are 17.4%, 16.6%, 17.7% respectively. The impact toughness is 99J/cm2 and the average grain size reaches about 7μm. Compared to the traditionally heavy rolling equipment, micro roller this paper used has transformative cost advantage to achieve high values of comprehensive mechanical properties.