  The new generation internal beam dump of the Super Proton Synchrotron (SPS)
at CERN will have to dissipate approximately 270 kW of thermal power, deposited
by the primary proton beam. For this purpose, it is essential that the cooling
system features a very efficient heat evacuation. Diffusion bonding assisted by
Hot Isostatic Pressing (HIP) was identified as a promising method of joining
the cooling circuits and the materials of the dump's core in order to maximise
the heat transfer efficiency. This paper presents the investigation of HIP
assisted diffusion bonding between two CuCr1Zr blanks enclosing SS 316L tubes
and the realisation of a real size prototype of one of the dump's cooling
plate, as well as the assessments of its cooling performance under the dumps
most critical operational scenarios. Energy-dispersive X-ray (EDX)
spectroscopy, microstructural analyses, measurements of thermal conductivity
and mechanical strength were performed to characterize the HIP diffusion bonded
interfaces (CuCr1Zr-CuCr1Zr and CuCr1Zr-SS316L). A test bench allowed to assess
the cooling performance of the real size prototype. At the bonded interface,
the presence of typical diffusional phenomena was observed. Moreover, measured
tensile strength and thermal conductivity were at least equivalent to the
lowest ones of the materials assembled and comparable to its bulk properties,
meaning that a good bonding quality was achieved. Finally, the real size
prototype was successfully tested with an ad-hoc thermal test bench and with
the highest operational thermal power expected in the new generation SPS
internal beam dump.
