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The traditional tungsten alloy is easily formed in the penetration process the mushroom head can not be a good adiabatic shear band . Mn, low thermal conductivity of the adiabatic shear band formation is very favorable . And the low melting point of the Mn , Mn and Ni to form an adhesive phase and a Ni-Fe , Ni-Co as a binder phase compared to its liquid phase generating temperature lower to about 300 ℃ . In this experiment, W, Ni, Mn , and nickel-manganese alloy powder as raw material , the use of liquid-phase sintering prepared 90W-Ni-Mn alloy . The main raw material powder performance , alloy composition , sintering temperature and holding time , heat treatment and swaging deformation effect on the mechanical properties of the alloy . Adoption the Archimede method measuring the density of the sample ; the fracture micro components using The metallographic microscope sample microstructure , scanning electron microscopy (SEM) observation fractography using spectroscopy (EDS) analysis . The results show that : 1 ) the same sintering temperature and holding time , the density and tensile strength of the nickel- manganese alloy powder prepared the 90W-6Ni-4Mn alloy are higher than the elemental powder and alloys . The sintering temperature of 1280 ° C , the holding time 120min prepared the 90W-6Ni-4Mn alloy by alloy powder , the relative density of 96.5% , the tensile strength of 675.5MPa . 2) Since the characteristics of Mn element is easy oxidation , 90W-Ni-Mn alloy can not be sintered to full density with the increase of the Mn content , the relative density and the tensile strength of the alloy are decreased gradually . Mn content of 2% , the sintering temperature of 1280 ° C , the holding time 120min , the the alloy relative density of 97.32% , the tensile strength of 702.5MPa . 3 ) alloy solid solution after quenching , tungsten - tungsten particles interface on small particles similar to the binding phase . Increase the interfacial bond strength , thus improving the mechanical properties of the alloy . Tensile strength and ductility of the vacuum heat treatment to reduce the hydrogen content of the interface and the matrix phase of the alloy , to elimination of hydrogen embrittlement , and thickening of the diffusion layer of tungsten particles and a binder phase , the bonding strength of the two phases of the alloy can be enhanced , improved alloy make the 90W-6Ni-4Mn elongation reached 14.8% . 4) after swaging , the tungsten particles have a different degree of deformation , the increase in strength of the tungsten particles to increase in the tensile strength of the alloy , the tensile strength of of 90W- 6Ni 4Mn of 693.38MPa to 782.4MPa , and the rate of alloy extending from 14.8% down to 6.6% .
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