Microstructure characterization and mechanical property of short-duration hot pressing assisted additive manufacturing TiB₂/AlSi10Mg alloy

TiB₂-reinforced AlSi10Mg composites via laser powder bed fusion (LPBF) faces a critical challenge: eliminating porosity without sacrificing the fine microstructure essential for strength. This study introduces a novel short-duration hot pressing technique (SdPH) that resolves this dilemma. Unlike conventional hot isostatic pressing, SdPH employs uniaxial pressure (10 MPa) at moderated temperatures for ≤1 min, exploiting the disparity between pore closure and diffusion-driven coarsening. Multiscale characterization reveals that SdPH reduces porosity from 0.394 % to 0.294 %, while retaining the as-built microstructure (nanoscale Si precipitates and full-cellular structure). SdPH -AlSi10Mg/TiB₂ sample exhibited good mechanical properties with a yield strength of 267 MPa, an ultimate tensile strength of 457 MPa, and an elongation of 4.6 %. This work redefines post-AM processing paradigms, proving that transient thermomechanical coupling can overcome the longstanding trade-off between densification and microstructural degradation during heat treatment.