Wave Processes and Mass Transfer on the Copper-Stainless Steel Interface under Solid Phase Bonding by High-Temperature Rolling

Abstract

The paper presents the study of hierarchy of deformation wave-processes from nano-to macro-structural level, which takes place in dissimilar materials, bonded by high-temperature vacuum rolling in solid phase. The focus was on the processes that occur on the interface of the bonded materials: mass trasfer of impurities and alloying elements stimulated by deformation, the study of nano-and micro-hardness.

THERMAL ANNEALING EFFECTS ON MICROSTRUCTURE AND MECHANICAL PROPERTIES OF THE Ta-W-Ta SOLID PHASE JOINTS FOR NEUTRON PRODUCING TARGETS OF THE RESEARCH NUCLEAR FACILITY “SOURCE OF NEUTRONS”

“…This fact is the evidence of the preferential niobium advance through the interfaces even at the stage of joining materials due to its increased diffusion mobility in comparison with neighboring materials. The same effect was also experimentally observed in such material pairs like Cu-Pb and stainless steel-Cu and others and described in [5,6,9]. With the annealing temperature increasing this effect intensifies (Fig.…”

“…A common technological technique for the vacuum hot roll bonding, is the possibility of influencing the transition zone formation process by introducing of a intermediate layer material into the contact zone [11] in order to reduce the rolling temperature, the reduction pressure and accelerate the high-quality solid-phase junctions formation when dissimilar materials joining is taking place. From this point of view it is appropriate to use intermediate layers that facilitate the volumetric interaction processes development in the contact zone and activate the joining process that is the materials with high plastic properties possessing a lower plastic deformation resistance comparing to those of the base metals [4][5][6][7][12][13][14]. As a rule the main requirement for such layers materials is the ability to form the solid solutions with both joining materials [9,15].…”

“…The laminates are a specific type of junctions and play an important role in today's innovative solutions where multitask solutions are required. The creation of the refractory metals solid-phase junctions with high tightness which can prevent the radioactive products release from tungsten into the cooling water is possible by using the vacuum hot roll bonding (VHRB) [3][4][5][6][7][8][9]. The point of this method is heating and subsequent entire batch deformation consisting of materials layers to be joined by means of roll bonding under the vacuum conditions.…”

The Deformation Value Effect on the Ta-W-Ta Solid-Phase Junction Nature With Intermediate Ti (Titanium) Interlayers for the Neutron Producing Target of the Neutron Source

“…The vacuum hot roll bonding (VHRB) is one of the most relevant and modern methods of refractory metals joining due to their mutual high-temperature vacuum friction [6][7][8][9][10][11][12][13][14][15][16]. Using a combined way for the solidphase junctions creation based on such a pair of refractory metals as tantalum-tungsten which includes the CVD and VHRB methods it was possible to obtain high-quality high-strength solid-phase tantalumtungsten-tantalum junctions with titanium interlayers, at much lower technological parameters, suitable for neutron producing targets at the NRF 'Neutron Source' at NSC KIPT.…”