A manufacturing process of a hot stamped coated part comprising the following successive steps, in this order : providing a hot rolled or cold rolled steel sheet comprising a steel substrate and an aluminium-silicon alloy precoating, the precoating containing more than 50% of free aluminium and having a thickness comprised between 15 and 50 micrometers, then cutting the steel sheet to obtain a precoated steel blank, then heating the blank under non protective atmosphere up to a temperature T
i comprised between T
e - 10°C and T
e , Te being the eutectic or solidus temperature of the precoating, then heating the blank from the temperature T
i up to a temperature T
m comprised between 840 and 950°C under non protective atmosphere with a heating rate V comprised between 30°C/s and 90°C/s, V being the heating rate between the temperature T
i and the temperature T
m , in order to obtain a coated heated blank, then soaking the coated heated blank at said temperature T
m for a time t
m comprised between 20s and 90s, then hot stamping the blank in order to obtain a hot stamped coated part, then cooling said stamped part at a cooling rate in order to form a microstructure in the steel substrate comprising at least one constituent chosen among martensite or bainite.