Modeling additive manufacturing processes requires numerical methods capable of accommodating continuous material addition, evolving domain boundaries, and thermally induced mechanical effects. Conventional Finite Element Method (FEM) formulations face limitations in such applications, as repeated remeshing or mesh-tracking procedures are often required to represent progressive material deposition, leading to increased numerical complexity and potential degradation of solution accuracy. The Particle Finite Element Method (PFEM) provides an alternative approach by representing the computational domain as a collection of particles from which a finite element mesh is constructed to solve the governing equations, enabling evolving geometries to be treated within a consistent numerical framework while maintaining mesh quality throughout the simulation [1]. In this work, PFEM is employed for the three-dimensional numerical simulation of a simplified additive manufacturing process. The process is modeled through the deposition of material particles onto the specimen surface, leading to an evolving computational domain. The analysis is performed within a thermomechanically coupled transient framework in which temperature and displacement boundary conditions are prescribed to represent the imposed thermal and mechanical constraints during the process. This approach allows domain evolution to be modeled without reliance on explicit interface tracking or advanced mesh adaptation procedures [2]. A thermoelastic constitutive model is adopted to describe the thermomechanical response of the material during deposition. The formulation incorporates temperature-dependent elastic properties, allowing the influence of temperature variations on the mechanical response to be captured. The resulting temperature, displacement, and stress fields are evaluated to characterise the behavior of the deposited material. References- [1] Cremonesi, M., Franci, A., Idelsohn, S. R., et al., A state of the art review of the Particle Finite Element Method (PFEM), Archives of Computational Methods in Engineering, Vol. 27, pp. 1709–1735, 2020. [2] Schewe, M., Noll, I., Bartel, T., Menzel, A., Towards the simulation of metal deposition with the Particle Finite Element Method and a phase transformation model, Computer Methods in Applied Mechanics and Engineering, Vol. 437, Art. No. 117730, 2025.