Study on characteristics of Ni-W-B composites containing CeO_2 nano-particles prepared by pulse elec

来源 :Journal of Rare Earths | 被引量 : 0次 | 上传用户:LHL1111111111
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Ni-W-B composites containing CeO2 nano-particles on the surface of 45 steel were prepared by pulse electrodeposition,and the in-fluence of pulse frequency,pulse duty circle and heat treatment temperature on the structures and properties were investigated.The results in-dicated that the pulse co-deposition of Ni,W,B and CeO2 nano-particles led to Ni-W-B/CeO2 composites possessing higher microhardness and better wear resistance when heat-treated at 400 oC for 1 h.The microhardness of 636 HV and the deposition rate of 0.0281 mm/h of the as-deposited alloy were the highest at pulse frequency of 1000 Hz,pulse duty circle of 10% and pulse average current density of 10 A/dm2.The composites were mainly in the amorphous state and were partially crystallized as-deposited,and the crystallization trend was strength-ened when heat-treated at 400 oC.Decreasing pulse duty cycle from 75% to 10% was favorable to the refinement in grain structures and im-provement of microstructures.The crystal sizes of the composites were smaller by means of pulse electrodeposition. Ni-WB composites containing CeO2 nano-particles on the surface of 45 steel were prepared by pulse electrodeposition, and the in-fluence of pulse frequency, pulse duty circle and heat treatment temperature on the structures and properties were investigated.The results in-dicated that the pulse co-deposition of Ni, W, B and CeO2 nano-particles led to Ni-WB / CeO2 composites possessing higher microhardness and better wear resistance when heat-treated at 400 oC for 1 hour. The microhardness of 636 HV and the deposition rate of 0.0281 mm / h of the as-deposited alloy were the highest at pulse frequency of 1000 Hz, pulse duty circle of 10% and pulse average current density of 10 A / dm2. composites were mainly in the amorphous state and were partially crystallized as-deposited, and the crystallization trend was strength-ened when heat-treated at 400 oC. Decreasing pulse duty cycle from 75% to 10% was favorable to the refinement in grain structures and im-provement of microstructures. of the composites were smaller by means of pulse electrodeposition.
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