Process Optimization for Suppressing Cracks in Laser Engineered Net Shaping of Al2O3 Ceramics

• DOI: 10.1007/s11837-016-2191-8
• Publication Date: 2016-11-21T23:28:07Z
• Authors: F. Y. Niu; D. J. Wu; S. Yan; G. Y. Ma; B. Zhang
• Keywords: Brittleness

Direct additive manufacturing of ceramics (DAMC) without binders is a promising technique for rapidly fabricating high-purity components with good performance. Nevertheless, cracks are easily generated during fabrication as a result of the high intrinsic brittleness of ceramics and the great temperature gradients. Therefore, optimizing the DAMC process is a challenge. In this study, direct fabrication of Al2O3 single-bead wall structures are conducted with a laser engineered net shaping (LENS) system. A new process optimization method for suppressing cracks is proposed based on analytical models, and then the influence of process parameters on crack number is discussed experimentally. The results indicate that the crack number decreases obviously with the increase of scanning speed. Single-bead wall specimens without cracks are successfully fabricated by the optimized process.