| Metal beryllium has widely applied to the nuclear, space flight and aeroplane industry due to the characteristic of low density, high strength ratio, high specific heat and excellent thermal property. In general, the main methods to bond Be with the other materials have melting welding, brazing, diffusion bonding and glued joint, et al. The glued joint of Be with the other materials have the shortcomings such as the low strength, the easy aging and no enduring high temperature. The melting welding would result in the thermal crack and cannot be used to bond the big and bended parts due to the low welding depth. It has been showed that it is very difficult to bond beryllium with stainless steel due to weld stress and crack resulting from brittle inter-phase. So brazing and diffusion bonding are studied in this paper.It has been showed aboard that brazing and diffusion bonding is good methods to bond beryllium and stainless steel, but there are brittle inter-phase and the crack in bonding zone. The parameter and interlayer material choose, the bonding interface characteristics, the diffusion mechanism and the inter-phase formation mechanism are ambiguous, so it need to be further studied. The model of diffusion composition field isn't reported.In this paper, Be and HR-1 stainless steel were bonded by brazed and diffusion bonded. The composition, microstructure and proprieties of the bonding area are analyzed. In order to overcome and reduce brittle-phase, some technology are used and the properties are improved. Meantime, the element distribution in bonding joint of Be and HR-1 stainless steel is first modeled by finite element method. These studies have an important significance to design reasonable bonding technology and obtain excellent bonding joint. Lastly, the adsorption, oxidation and machining damage of Be were studied because of the importance of Be surface for bonding Be and HR-1 stainless steel.Be and HR-1 stainless steel was bonded at the different holding temperature, holding time, holding pressure and interlayer material. The joint strength was tested, and the fracture was observed with scanning electron microscopy(SEM). The hardness and elastic module of the joints were analyzed with nano-indenter, the microstructure was analyzed with optical microscopy and SEM, and the composition was analyzed with Auger Electron Spectroscopy (AES).There was a rapid diffusion path in Be. Firstly Cr, Fe, Ni, Mo elements segregated at interface and then diffused along grain boundary, when Be and HR-1 stainless steel were directly bonded at the holding temperature of the range from 750-1050℃, Be11Fe, Be5Fe,Be2Fe,BeCr, Be2Cr, Be12Cr, Be12Ni5, Be12Mo compounds are formed at interface and diffusion zone with peeling diffusion bonding joint. There were amount of inter-phases in bonded joints at the holding temperature of the range from 800-950℃,then the joints are very brittle. The sort and amount of the inter-phases at the holding temperature 750 and 1050 ℃ was less, so the strength of the joint was increased. This suggest that the bad properties of the joints between Be and HR-1 stainless steel are due to segregation of elements in diffusion zone and formation of brittle phases. So controlling the holding temperature and time can prevent from segregating at interface and forming brittle phases, then increase strength of Be and HR-1 stainless steel joint.Be and HR-1 stainless steel was also bonded by hot isostatic pressure bonding whose technology was novel, The interlayer material Ag, Al, Cu, Ag/Al and Cu/Ni were selected, which were coated by magnetron sputter deposition. Ag and Cu/Ni were the best interlayer for bonding Be and HR-1 stainless steel. The tensile strength of Be/Ag/HR-1 stainless steel joint and Be/Cu/Ni/HR-1 stainless steel joint are 64 MPa and 49 MPa, respectively. It is showed that the bonding technological parameter control is difficult when Cu, Al, Ag/Al interlayer are selected.It is showed that the holding pressure was closely relative with surface roughness. Diffusion width...
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