Analytical modelling and experimental study of the cladding characteristics of a laser powder-fed additive manufacturing process

To avoid the effects of the overlap phenomenon among powder particles, the concept of an effective particle number was introduced, and multi-parameter analytical models for laser powder-fed additive manufacturing (LPF-AM) cladding geometric characteristics were established based on the laws of energy and mass conservation. Experimental research on the LPF-AM of a FeCr alloy was carried out, and the theoretical results are discussed and compared with the experimental data from the perspective of the laser energy density and powder density. The results showed that the cladding area was proportional to both the laser energy density and powder density. The mixing area and dilution rate decreased gradually with increasing powder density, while they increased first and then decreased with increasing laser energy density. The analytical model calculation values fit well with the experimental measurements. The microstructure of the cladding layer and substrate showed good metallurgical bonding, and the micro-hardness variation from the mixing to the cladding zone ranged from 423 to 627 HV.