Effect of Surface Abrasive Treatment on the Strength of Galvanised Steel Sheet Adhesive Joints

The surface morphology and microstructure of galvannealed steel sheet (GA) coatings prepared at different galvannealing parameters were analyzed by X-ray diffraction and SEM, and powdering amount of GA coating was investigated by the double-Olsen powdering tester. The results show that when the Al contents below 0.16 wt%, the Ra of GA coating surface was measured namely below 1.0 μm, and powdering amount of GA coating was below 30 mg/m2, it is within a reasonable value required by automotive makers. After that with the Al contents increased in zinc liquid the amount of powdering increased, this means that the powdering resistance performance of GA coating not only depended on the iron content in the coating, but depended on the roughness profiles of the surface coating. When the galvanizing coating with 0.22 wt% Al content and galvannealing at 500 °C, with the inhibition effect of Fe2Al5Znxinhibit layer, the thickness of δ1k-phase was different in the GA coating, which deteriorated the powdering resistance performance of GA coating.

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Effect of Surface Segregation during Annealing and Surface Oxide Film on Phosphate Coating of Cold Rolled Steel Sheet

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.66.7_945 ◽

1980 ◽

Vol 66 (7) ◽

pp. 945-952 ◽

Cited By ~ 6

Author(s):

Shigeru WAKANO ◽

Noriaki USUKI ◽

Minoru NISHIHARA ◽

Nobukatsu FUJINO

Keyword(s):

Oxide Film ◽

Steel Sheet ◽

Surface Segregation ◽

Surface Oxide ◽

Phosphate Coating ◽

Rolled Steel ◽

Surface Oxide Film ◽

Cold Rolled Steel ◽

Cold Rolled ◽

Effect Of Surface

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Effect of Surface Treatment on Adhesive Strength Properties of Al/PC Adhesive Joints

Transactions of the Korean Society of Mechanical Engineers A ◽

10.3795/ksme-a.2003.27.5.840 ◽

2003 ◽

Vol 27 (5) ◽

pp. 840-847

Keyword(s):

Surface Treatment ◽

Adhesive Strength ◽

Strength Properties ◽

Adhesive Joints ◽

Effect Of Surface

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Effect of nano ZnO containing sol-gel coating on galvanised iron sheet

Pigment & Resin Technology ◽

10.1108/prt-01-2014-0007 ◽

2015 ◽

Vol 44 (4) ◽

pp. 239-249 ◽

Cited By ~ 3

Author(s):

Akshya Kumar Guin ◽

Manish Bhadu ◽

Mohua Sinhababu ◽

Tapan Kumar Rout ◽

G. Udayabhanu

Keyword(s):

Corrosion Resistance ◽

Water Permeability ◽

Steel Sheet ◽

Salt Spray ◽

Sol Gel ◽

Nano Zno ◽

Content Type ◽

Galvanised Steel ◽

Passivation Treatment ◽

Hexavalent Chrome

Purpose – This paper aims to investigate the potential of sol-gel coating as replacement for hazardous hexavalent chrome passivation treatment for galvanised iron (GI) sheet. Generally, corrosion resistance properties of the GI sheet are increased by hexavalent chrome passivation treatment. But hexavalent chrome is hazardous and not environment friendly. Design/methodology/approach – The aim of this study was to understand the effect of nano zinc oxide (ZnO) on corrosion behaviour of sol-gel coating prepared by hydrolysis of the 3-(Glycidoxy propyl) methyl diethoxy silane (GPTMS) and tetra-ethyl-orthosilicate (TEOS). The morphology of the film was characterised by a scanning electron microscope (SEM). The corrosion resistance of the coated samples was evaluated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarisation curve and salt spray test. Findings – From a different corrosion resistance study, it has been observed that sol-gel coating doped with 1 per cent nano ZnO rendered maximum corrosion protection. Beyond 1 per cent of nano ZnO, corrosion resistance property of coated galvanised steel sheet decreased drastically which may be due to agglomeration of nano ZnO and high water permeability of coated galvanised steel sheet. Research limitations/implications – The anti-corrosive property of the coating can be tested by means of atmospheric exposure which produces a real-time evaluation of the anti-corrosive nature of the coating under natural conditions rather than using an accelerated laboratory test. Practical implications – It may be useful for other metal industry like aluminium. The work can be used as a guiding chemistry for development of chrome-free passivation for aluminium. Social implications – It has the potential to replace hexavalent chrome passivation. Originality/value – The use of nano ZnO in sol-gel polymer matrix for the development of corrosion resistant chrome-free polymer coating for galvanised steel sheet and its corrosion resistance study (EIS curve fitting, capacitance value and water permeability) is a novel approach in this research.

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