The effects of chemical compositions and microstructures on wearability properties of overlaid corrugating roll were studied, and the factors governing the hardness and the wearability of overlaid layer were explored....The effects of chemical compositions and microstructures on wearability properties of overlaid corrugating roll were studied, and the factors governing the hardness and the wearability of overlaid layer were explored. The results show that the hardness and wearability of the overlaid layer significantly rise with the increase of the mass fraction of various types of eutectic, but the crack-resistance falls. The chief factor governing the hardness of overlaid layer is the matrix microstructure, especially the amount of austenite; and the second is the amount of carbide. The principal factor governing the wearability of overlaid layer is the amount of special carbide, particularly the amount of eutectic; and the second is the hardness of overlaid layer. Meanwhile, high alloying electrodes may cause the gear-surface hardness of corrugating roll to be higher than 63HRc, and may enhance the wearability of the gear-surface of corrugating roll by a factor of 5.63 and 9.08.展开更多
This study was carried out to evaluate the resistance of overlaid pavement incorporating stress absorbing membrane interlayers to permanent deformation. In this study, the permanent deformation of the interlayer mixtu...This study was carried out to evaluate the resistance of overlaid pavement incorporating stress absorbing membrane interlayers to permanent deformation. In this study, the permanent deformation of the interlayer mixtures was determined using the RLAT （repeated load axial text） carried out in the Nottingham Asphalt Tester. Also, a test pavement was constructed in the laboratory to assess the resistance to permanent deformation of overlaid pavement incorporating SAMIs （stress absorbing membrane interlayers）. The test pavement was divided into two along the centre line. Each of the divisions has three sections--two having SAMIs and one without SAMIs. The pavement was instrumented and trafficked. Trafficking was stopped when the pavement was deemed to have failed. The results showed that the measured permanent deformation values of the control sections were less than the sections having SAMIs. The increased permanent deformation values indicate that the introduction of SAMIs causes more vertical/horizontal deformation of the pavement. It was also found that the permanent deformation values varied depending on the composition and thickness of the SAMIs.展开更多
文摘The effects of chemical compositions and microstructures on wearability properties of overlaid corrugating roll were studied, and the factors governing the hardness and the wearability of overlaid layer were explored. The results show that the hardness and wearability of the overlaid layer significantly rise with the increase of the mass fraction of various types of eutectic, but the crack-resistance falls. The chief factor governing the hardness of overlaid layer is the matrix microstructure, especially the amount of austenite; and the second is the amount of carbide. The principal factor governing the wearability of overlaid layer is the amount of special carbide, particularly the amount of eutectic; and the second is the hardness of overlaid layer. Meanwhile, high alloying electrodes may cause the gear-surface hardness of corrugating roll to be higher than 63HRc, and may enhance the wearability of the gear-surface of corrugating roll by a factor of 5.63 and 9.08.
文摘This study was carried out to evaluate the resistance of overlaid pavement incorporating stress absorbing membrane interlayers to permanent deformation. In this study, the permanent deformation of the interlayer mixtures was determined using the RLAT （repeated load axial text） carried out in the Nottingham Asphalt Tester. Also, a test pavement was constructed in the laboratory to assess the resistance to permanent deformation of overlaid pavement incorporating SAMIs （stress absorbing membrane interlayers）. The test pavement was divided into two along the centre line. Each of the divisions has three sections--two having SAMIs and one without SAMIs. The pavement was instrumented and trafficked. Trafficking was stopped when the pavement was deemed to have failed. The results showed that the measured permanent deformation values of the control sections were less than the sections having SAMIs. The increased permanent deformation values indicate that the introduction of SAMIs causes more vertical/horizontal deformation of the pavement. It was also found that the permanent deformation values varied depending on the composition and thickness of the SAMIs.
