Cold spray additive manufacturing metal knitting: Process parameters effect on aluminum components geometry

As cold spray (CS) has evolved into a 3D printing method, known as CS additive manufacturing (CSAM), new challenges have emerged: geometry accuracy, materials properties, and operation costs. This research is at the forefront of addressing these challenges, particularly focusing on the innovative approach of the new CSAM metal knitting (MK) strategy parameters. This approach influences the morphology of thin, straight walls and the deposit microstructure, hardness, strength, and abrasion wear. It was evaluated that a heat treatment (HT) of the CSAM MK deposits increased the tensile strength up to 300 % and reached a hardness close to 50 HV 0.3 . Regarding the costs, this work deposits an inexpensive irregular pure Al powder instead of the expensive gas atomized spherical ones seen for many AM processing. This work presents how the CSAM MK can be optimized for a high deposit geometry accuracy and control, as well as how a simple HT can overtake the CSAM MK cons of high porosity and lower cohesion of particles. Besides that, using a low-cost feedstock powder is one more attractive for the CSAM use for 3D printing of metals.