Heat Treatment of A20X Alloy Manufactured Using Laser Powder Bed Fusion

The A20X alloyAlloys, a metal matrix compositeMetal matrix composites (MMC) designed for laser powder bed fusionLaser powder bed fusion (LPBF), requires precipitation hardening treatment to achieve optimal mechanical propertiesMechanical properties. This study investigates the effect of temperature and duration of heat treatmentHeat treatment on the microstructureMicrostructure and mechanical propertiesMechanical properties of LPBF A20X. The effects of heat treatmentHeat treatment temperature and duration on the as-printed material were evaluated using mechanicalMechanical testing and microscopic characterizationCharacterization. In total, three different regimes reflecting the alloyAlloys’s response to heat treatmentHeat treatment were observed. For low-temperature (180–370 °C) heat treatmentsHeat treatment, material softening (up to 26%) proportional to temperature and duration of treatment was evident. Samples treated at medium temperatures (430–480 °C) showed hardening (from 90 up to 115 HV) with increasing temperature and remained unchanged with dwell time. This is attributed to the dissolutionDissolution of precipitatePrecipitates-formers (Cu/Mg/Ag) promoting solid solution strengthening. At high temperaturesHigh-temperature (≥500 °C), the alloyAlloys entered the super-saturation regime causing relatively constant hardnessHardness (~117 HV).