GB/T 30789.9-2014Paints and varnishes -- Evaluation of degradation of coatings -- Designation of quantity and size of defects, and of intensity of uniform changes in appearance -- Part 9: Assessment of degree of filiform corrosion (English PDF)

Foreword

GB/T 30789 "Paints and varnish coating aging rating number and size of the defect and the identity of the extent of uniform changes in appearance." Divided into the following nine sections.

--- Part 1. General and identification systems;

--- Part 2. Evaluation of blistering levels;

--- Part 3. Evaluation of rust grade;

--- Part 4. Evaluation cracking grade;

--- Part 5. Evaluation of flaking grade;

--- Part 6. Assessment of degree of chalking tape method;

--- Part 7. Method for Evaluation of velvet cloth chalking rating;

--- Part 8. scribe or other artificial defect assessment and corrosion peeling peripheral level;

--- Part 9. Evaluation of filiform corrosion level.

This section GB/T Part of 930,789.

This section drafted in accordance with GB/T 1.1-2009 given rules.

This section uses the translation method identical with ISO 4628-10:2003 "Paints and varnish coating aging quantity evaluation of defects and large Part 10 small degree of uniformity and appearance change logo. Evaluation of filiform corrosion level. " this part is proposed by the China Petroleum and Chemical Industry Association.

This part of the National Standardization Technical Committee and the pigment coating (SAC/TC5) centralized.

This section drafted by. CNOOC Changzhou coating Chemical Research Institute, Changzhou brilliant Chemical Co., Ltd. Shaanxi limited Baotashan paint Shares the company, Zhuhai fluorine Technology Co., Ltd, Nanjing Product Quality Supervision and Inspection Institute, Shenzhen Hirota Decoration Group Co., Ltd., of Ocean Power Research Institute.

1 Scope

This section GB/T 30789 is given by measuring the scratches caused by filamentous corrosion longest filament length L and the most frequent Filaments filiform corrosion length M thus assessed approach.

Part A of this Appendix with the legend of filiform corrosion longest filament length L and the most frequently occurring filaments of different lengths M grade. Appendix A test model in Figure 12 Comparative figures can not replace the necessary assessment (Tier 1 or Tier 2).

2 Terms and definitions

The following terms and definitions apply to this document.

Filiform corrosion Occur in paint, varnish or related products, coatings, usually from the exposed edges of coating or partial destruction of a linearly beginning corrosion.

Note 1. the usual filiform corrosion and extend the length direction is erratic, but they can be regarded as approximately parallel and approximately of equal length.

Note 2. filiform corrosion may also occur under other protective coating.

Note 3. In general, the filamentous texture metal corrosion along the substrate surface extending across not cross, and was originally caused by the corrosive ions.

[GB/T 13452.4-2008 and GB/T 26323-2010]

3 Ratings