아크열원 DED 공법의 STS 316L 와이어송급 적층공정 및 기계적물성 평가

Abstract

Additive manufacturing of novel metals has received much attention as an alternative to traditional subtractive manufacturing because of its high material efficiency (cost reduction in terms of material efficiency or the Buy-to-Fly ratio), shorter lead time and higher design flexibility (new design possibilities). When compared with the laser and powder additive manufacturing, the arc and wire additive manufacturing is known to have higher material efficiency, higher deposition rate, and cheaper investment and maintenance. Therefore, in this work, we used cold metal transfer (CMT) gas metal arc welding (GMAW) for arc and wire additive manufacturing of STS 316L and perform a parametric study. It was found that the cooling time for the interpass temperature to cool down to 350℃ is dependent on the number of the deposition layer and the travel speed. We also investigate the effect of the travel speed, the travel direction, the contact tip to work distance (CTWD) and number of the deposition layer on the characteristics of the deposited sample. The spatial inconsistencies of the tensile strength and the hardness are observed to increase as the travel speed is increased. Finally, we find that anisotropic metallurgical properties are observed throughout the deposited STS 316L.