The Study On Plasma Spraying Preparation Process Of Iron-based Amorphous Alloy Coating And Its Properties

As a new material of new and high technology, iron-based amorphous alloy has been widely applied in business, of which Fe78Si9B13and Fe73.5Cu1Nb3Si13.5B9amorphous alloy strip are the most widely in use. However, the rapid development of iron-based amorphous alloy brings the increase of waste material in the production process. How to deal with the iron-based amorphous alloy scrap strip economically and efficiently and be two times used have been become an urgent problem to be resolved.In this paper, different granularity of Fe-based amorphous and nanocrystalline powders were got through annealing, ball milling, sieving of Fe-based amorphous alloy scrap the strip. Fe-based amorphous coating had been prepared on Q235steel substrate using plasma spraying process. The microstructure of Fe-based amorphous coating were analyzed by metallographic microscope and scanning electron microscope. The phases were examined by X ray diffraction. At the same time, the porosity of coating, microhardness, bond strength and wear resistance were tested and analysed systematacially. And the effects of different spraying powder coating on the amorphization degree, porosity, interface binding were also studied.The Fe based powder prepared by embrittlement and ball-milling process were analysised by XRD. The results show that Fe78Si9B13alloy powder is amorphous and Fe73.5Cu1Nb3Si13.5B9alloy powder exists part of the nanocrystalline particles. The prepared iron-based amorphous coating is uniform on structure and smooth on surface. XRD analysis shows that the coating is composed by amorphous phase and dispersion a-Fe(Si) nanocrystalline and the amorphization degree of Fe78Si9B13coating is higher than that of Fe73.5Cu1Nb3Si13.5B9coating and the coating mixture.Combined with the coating porosity, when the arc voltage is60V, arc current is500A, spraying distance is100mm, the properties of the coating are the best in the plasma spraying process. The lowest coating porosity of Fe78Si9B13alloy powder, Fe73.5Cu1Nb3Si13.5B9powder, mixed powder is11.30%,16.07%,14.60%, respectively. The microhardness value of Fe78Si9B13coating, Fe73.5Cu1Nb3Si13.5B9coating and mixed coating is918.7,727.7,661.7, respectively under the best process, of which Fe78Si9B13coating microhardness value is the best. Hardness value on coating surface is lower than on the coating middle section. When moving to the outer end of the cross section of (far away from the base end), microhardness values begin to decline, coating microhardness values show "hill shape" of the bigger middle, two smaller ends. The wear amount of Fe78Si9B13coating is less than that of Fe73.5Cu1Nb3Si13.5B9coating and the mixed coating on abrasive wear test. The stress of Fe78Si9B13coating, Fe73.5Cu1Nb3Si13.5B9coating and mixed coating is6.4KPa,5.8KPa,6.4KPa, respectively during the coating fracture on three point bending test. The test results indicate that the bond strength of Fe78Si913o coatings is better than that of Fe73.5Cu1Nb3Si13.5B9coating and the coating mixture.Comprehensive study showed that the Fe78Si9B13spraying powder coating has better properties than Fe73.5Cu1Nb3Si13.5B9spraying powder and mixed spraying powder when the arc voltage is60V, arc current is500A and spraying distance is100mm in plasma spraying process.