Additively manufactured ultra-high vacuum chamber below $10^{-10}$ mbar
Metal-based additive manufacturing (AM) represents a paradigm change in engineering and production methods across multiple industries and sectors. AM methods enable mass reduction and performance optimisation well beyond that achievable via conventional manufacturing, thereby impacting significantly on aerospace and space technologies. Technologies relying on high and ultra-high vacuum (UHV), such as x-ray photo-electron spectroscopy, photo-sensors, cameras and cryostats, could also benefit greatly from AM. Despite recent advances in AM processing of metals, additively manufactured UHV chambers have so far not been achieved. Reducing the mass of UHV equipment is particularly critical for the development of portable cold atom systems, which are expected to underpin the next generation of sensing and timekeeping technologies and to allow novel space-based sensors for fundamental research. We demonstrate here an additively manufactured UHV chamber reaching a pressure below $10^{-10}$ mbar, enabling a cloud of cold $^{85}$Rb atoms to be trapped - the starting point for many precision timekeeping and sensing devices. The chamber is manufactured from aluminium alloy AlSi10Mg by laser powder bed fusion and has a mass of less than a third of a commercially-available equivalent. Outgassing analysis based on mass spectrometry was performed and it was demonstrated that even without active pumping the system remains in the $10^{-9}$ mbar regime for up to 48 hours.