Wire arc additive manufacturing (WAAM) is an effective method for fabricating lattice structure. The WAAM equipment of lattice structure, the design and fabrication technology of Al-based flux-cored wire, the laser constrained arc process and the diameter and angle control method of lattice rod were studied. Typical lattice structure application parts were manufactured. The WAAM equipment of lattice structure is composed of additive manufacturing unit, laser unit and monitoring unit. The Al-Cu-NiO alloy system of in-situ Al,2,O,3, phase Al alloy core wire was designed. The core wire with a diameter of 1.2 mm was prepared, and the deposition rod had low thermal conductivity. Laser excites a large number of neutral particles to ionize, so that the charged particles in the arc greatly increase the arc, which has a restraining and stabilizing effect on the arc and improves the forming accuracy. By controlling the volume and number of droplets in WAAM, lattice unit rods with different diameters of 2.5~7.0 mm can be manufactured. By controlling the lift and offset between the layers of the welding torch during WAAM process, lattice unit rods with different angles of 15°~90° can be prepared. The high-precision forming of planar lattice, cylindrical lattice and curved busbar lattice structures is fabricated by using the lattice structure WAAM technology. The average compressive strength of the lattice structure is 58.53 MPa. The uniform heat source is applied to the upper surface of the lattice test piece. The heat source temperature is 500 ℃. When the heat source is applied for 600 s, the lower surface temperature of the test piece is about 93 ℃, which has high bearing performance and thermal insulation performance.
metal lattice structureswire arc additive manufacturingaluminum alloyequipmentpowder core wire
Ma F， Yang H， Zhan M. Plastic deformation behaviors and their application in power spinning process of conical parts with transverse inner rib［J］. Journal of Materials Processing Technology， 2010， 210（1）： 180-189.
Zhan M， Yang H， Guo J， et al. Review on hot spinning for difficult-to-deform lightweight metals［J］. Transactions of Nonferrous Metals Society of China， 2015， 25（6）：1732-1743.
Carneiro V H， RaWson S D， Puga H， et al. Additive manufacturing assisted investment casting： A low-cost method to fabricate periodic metallic cellular lattices［J］. Additive Manufacturing， 2020， 33：101085.
Deshpande V S， Fleck N A， Ashby M F. Effective properties of the octet-truss lattice material［J］. Journal of the Mechanics & Physics of Solids， 2001， 49（8）：1747-1769.
Wadley H N， Norman A， Anthony G E. Fabrication and structural performance of periodic cellular metal sandwich structures［J］. Composites Science & Technology， 2003， 63（16）：2331-2343.
Wadley K. Lattice truss structures from expanded metal sheet［J］. Materials & Design， 2007， 28：507-514.
Kooistra G W， Deshpande V S， Wadley H. Compressive behavior of age hardenable tetrahedral lattice truss structures made from aluminium［J］. Acta Materialia， 2004， 52（14）：4229-4237.
ZHANG Z， Sun C， Xu X， et al. Surface quality and forming characteristics of thin-wall aluminium alloy parts manufactured by laser assisted MIG arc additive manufacturing［J］. International Journal of Lightweight Materials & Manufacture， 2018， 1：89-95.