Phase Transformations Of Ni-P Alloy Under Extreme Conditions

Ni₇₇P₂₃ amorphous alloy film can be produced up by electrodeposit. TheNi-P ingots were prepared by remelting and casting in an argon-arc furnace. Thesolidification was researched by fluxing and drop tube containnessless. And thecompression behavior of Ni₇₇P₂₃ amorphous alloy is investigated at roomtemperature using high pressure energy dispersive x-ray diffraction. The Ni₇₇P₂₃ was disposed by B2O3 which is used as a fluxing. It wassubstantiated that this method is effect to eliminate impurity, and it can be highlyundercooled, the effect of cycle times, superheating time and superheatingtemperature was investigated, the deeper undercooling we gained was 214K.The Phase morphologies of different undercooling was observed, which showsthat the microstructures are primary Ni3P dendrites and Ni-P eutectics.Compared with the equation solidification, the microstructures of primary Ni3Pdendrites were more bulky,By calculation, solute undercooling plays adominant role in crystal growth under lower undercooling. Solidified droplets are achieved by drop tube. The primary is Ni3P dendrites.With the decreasing of diameter of droplet, it was refinement of primary Ni3P.The relationship between drop time and sample temperature of differentdiameter was gained. And the solute transfer's modulus under gravitation andtiny gravitation were calculated. The effect of excess free volume for volume change of Ni₇₇P₂₃ amorphouswas researched by using high pressure energy dispersive x-ray diffraction. It isfound that the structure of Ni₇₇P₂₃ amorphous alloy is stable under pressures upto 30.5 GPa. The equation of state of the Ni₇₇P₂₃ amorphous alloy isdeterminated: -ΔV/V₀ =0. 08606P-3.2×P²+5.7×10^-6P³...