Cyclic Corrosion Tests in Japanese Industries

The article presents the results of work on improving the corrosion resistance of magnets of the REM–Fe–B system manufactured in China, by applying an ion-plasma coating of the SDP-1T + VSDP-13 system on an industrial vacuum-arc installation MAP-3. A comparative assessment of the tread protection of the vacuum-arc coating of the SP-1T + VSP-13 system was carried out with an already applied Ni–Cu–Ni coating under conditions of accelerated cyclic corrosion tests at a temperature of 300 °C. The coating of the SDP-1T + VSDP-13 system, applied in the FSUE «VIAM», creates a much more resistant protection of the magnets of the REM–Fe–B system from corrosion compared to the electroplating of the Ni–Cu–Ni system, manufactured in China.

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Susceptibility of Automobile Spring Steels to Wet-Dry Cyclic Corrosion Induced Environmental Embrittlement

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.297-300.933 ◽

2005 ◽

Vol 297-300 ◽

pp. 933-938

Author(s):

K. Kobayashi ◽

Shinichi Komazaki ◽

Toshihei Misawa ◽

T. Fukuzumi

Keyword(s):

Significant Influence ◽

Pitting Corrosion ◽

Experimental Results ◽

Strength Level ◽

Nacl Solution ◽

Rust Layer ◽

Corrosion Tests ◽

Environmental Embrittlement ◽

Cyclic Corrosion ◽

Spring Steels

The susceptibility to environmental embrittlement (EE) of automobile spring steels was investigated using six different steels. A SSRT test and TDS analysis were applied to specimens subjected to wet-dry cyclic corrosion tests in a NaCl solution. Experimental results revealed that the reduction in ductility after the corrosion tests was pronounced with increasing strength level. This degradation was closely associated with the resistance to pitting corrosion. Consequently, the hydrogen absorbed in steel and the corrosion pit as a geometric damage were responsible for the EE of spring steels. The hydrogen in rust layer had no significant influence on the EE.

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Effects of Mg Additions on Surface Morphology and Corrosion Resistance of Hot-Dipped Zn Coatings

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.273-276.300 ◽

2008 ◽

Vol 273-276 ◽

pp. 300-305 ◽

Cited By ~ 1

Author(s):

Lucia Suarez ◽

Frans Leysen ◽

C. Masquelier ◽

D. Warichet ◽

Yvan Houbaert

Keyword(s):

Corrosion Resistance ◽

Construction Material ◽

Coating Properties ◽

Surface Layers ◽

Corrosion Tests ◽

X Ray ◽

Cyclic Corrosion ◽

Wide Range ◽

Excellent Method

Steel is still the main construction material for automobiles, general equipment and industrial machinery. Hot dipping has been proven to be an excellent method of corrosion protection of steels for a wide range of applications worldwide. Coatings of Zn-Al alloys on steel sheet have high corrosion resistance due to the corrosion prevention ability from Zn and the passivation of Al Bath composition, immersion velocity/time and substrate composition are the hot dipping parameters that more influence on the thickness and corrosion resistance of the deposited coating. In order to study their influence small amounts of magnesium were added. Experiments were performed in a hot dipping simulator using different substrates, bath compositions and hot dipping parameters. Surface layers were characterised by: Scanning Electron Microscopy (SEM) and Energy dispersive X-Ray spectroscopy (EDX or EDS). Cyclic corrosion tests were performed in order to observe the corrosion resistance for different Zn-Al-Mg coatings. Results show that the microstructure and composition of the substrate strongly affect the desired coating properties. Nevertheless, the influence of the magnesium on coating thickness is relevant, increasing when added in small quantities in a molten bath of Zn-5wt %Al. The quality and microstructure of the coating is affected by the amount of Mg in the bath. Cyclic corrosion tests results show that the quality of the coating is affected by the amount of Mg in the bath.

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