Finite element thermal simulation of multi-layer deposition of Ti6Al4V5Cr alloy by µ-Plasma powder additive manufacturing

Abstract

Accurate prediction of temperature distribution and molten pool behavior in µ-plasma powder additive manufacturing (µ-PPAM) is critical for minimizing residual stress, thermal distortion, and deposition defects in complex metallic components. This paper presents a 3D finite element simulation (FES) for predicting temperature distribution across successive deposition layers and within the molten pool during the multi-layer deposition of Ti6Al4V5Cr alloy by the µ-PPAM process. Experimental validation was carried out using a customized µ-PPAM setup equipped with strategically positioned K-type thermocouples to record deposition temperatures. The simulated and experimental data showed good agreement, confirming the reliability of the model. The results reveal that the peak temperature of the thermal cycles increased along the build direction with deposition of successive 4 layers i.e., maximum temperature of fourth layer > third layer > second layer > first layer. This trend can be attributed to heat dissipation and accumulation as well as atmospheric cooling and residual heat. Each deposition layer undergoes simultaneous heating and cooling cycles throughout the deposition process and high-temperature zone within the molten pool expanded as the deposition height increased. This phenomenon is attributed to reduced heat losses through convection and radiation with deposition of more layers. Findings of the present study provide valuable insights for optimizing heat input, process parameters, and direction of deposition. It will facilitate effective utilization of µ-PPAM process by enhancing its quality and performance in manufacturing the complex metallic components by it. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2025.