涂层缺陷分析和处理Coating Failures Analysis and Handling•调查研究表明:A great deal of investigations indicatedthat:•80％的涂料的缺陷是由于施工不当造成的•Almost 80% of coating failures were caused by improperapplication.•20％是由于其它原因造成的•20% of coating failures werecaused by other matters.涂层中夹渣／有灰尘杂物Abrasive residues/Dust •喷砂与机械处理方法所产生的灰尘，锈皮等•Dust or other types ofcontaminations caused by blast-cleaning or mechanical pre-treatment process.•要特别注意脚手架上的的磨料和灰尘•Advert to abrasives/dust from the scaffoldings.•如果不清除的话，磨料夹渣和灰尘会与刚喷的涂层合为一体•Abrasive residues/dust may be left or incorporated in the fresh coats.底漆中夹渣引起锈蚀Rust spots due to residues in primer coat刷痕Brushing marks•漆刷不良，引起漆膜成高一道，低一道的不均匀条状•Uneven streaks caused by improper application with brush •高固体份涂料，不易进行刷涂•High solids paint may not be applied with brush.漆膜过厚Excessive film thickness•对靠溶剂挥发来干燥的涂料来说，漆膜过厚会导致溶剂残留在漆膜中，表层干燥，但是下层较软，容易引起涂层内聚力及与底材的附着力问题，并且涂层在以后可能会出现起泡。
•The solvent may be entrapped in films if applying the solvent evaporation coatings in excessive thickness. Surface drying but soft underneath may cause poor cohesion of coats and worse adhesion between the coats and substrates, otherwise blistering may beoccurred in service.•对于固化型涂料来说，会产生内部收缩，引起涂料开裂、剥落，这种现象在内角的流淌处较为常见•For the chemical curing coatings, interior shrinkage of coats may cause cracking, flaking if applying in excessive thickness. These defects usually occur at some corners of structures where to beprone to stack the paints.内角由于流挂产生局部堆厚而开裂Cracking at the corner due to stacking paints partially caused by sagging.溶剂在过厚的漆膜中截留The solvents were entrapped in excessive films and cause into the porous coat.流挂Runs and Sags •流挂的发生，通常是因为：Runs and sags caused by:•超过了规定的膜厚•Too high wet film thickness•加入过量的稀释剂•Too much thinner added•喷枪过分靠近被涂物表面•Spray guns too close to surface •施工时发现流挂，可以快速地用刷子抹平•Brushing to smoothen rapidly once runs and sags occur•干膜的流挂状态，打磨平整后重新薄涂一遍•Abrasion/sanding excessive runs/sags to smoothen and re-coat缩孔/ 鱼眼Fisheye •施工在有油脂、水份、硅油等污染物的表面。
这些油污和湿气可能是打磨工具或不干净的压缩空气带来的•Paint applied on oil/grease, moisture, silicone or other contaminations whichmay be caused by power tools orunclean pressure air•表面张力高的涂料也容易引起缩孔(如施工在具较高光泽度的油漆上面则其表面润湿性较差）•Painted on incompatible coating (Glossy paints give poor wetting)针孔/漏点Pinholes/Pores•以下情况下，极易发生针孔和漏点•Pinholes/Pores caused by:•压力过大Excessive air pressure•涂膜过厚Excessive film thickness•过份的通风或大风环境Too good ventilation or strong wind •喷涂时距离太远Too long spray distance•喷锌、喷铝和无机富锌底漆：•Spraying of Zinc, Aluminum and Inorganic zinc-rich primer:•表面多孔有空气在内，极易产生针孔•Porous substrate contains air inside may be prone to pinholing.•可以用稀释后的涂料薄喷30微米再涂下道漆,称之为雾喷/全喷技巧•Spraying a thin coat in 30 microns via additional thinning and apply the subsequent coat. It is so called “Mist coat/Tiecoat” technique.漏涂Holidays•局部没有涂上油漆称之为漏涂•Holidays are recognized as areas where the applicator has missed applying paint to that part of surface.•球扁钢的球头部位Behind bars ,stiffeners etc•粗糙焊缝At rough welding seams•切口和自由边On notches, cut outs and edges•其它难以喷涂的地方On other areas where is inaccessible to spray•喷涂不良Improper spray application:•行枪时走弧线，中间漆膜过厚，而两侧偏薄•Arcing/tilting the spray gun shall cause into heavy films in the middle and thin films at the beginnings and ends ofspraying.•形成针状点锈•Pin rusting may be formed.•最好的解决办法是对这些地方进行预涂/条涂，并且在喷涂过程中保证每道喷幅间重叠50%以搭接。
•The recommended method is that stripe coating prior to spray and overlap 50% of each pass or cross of spraying.干喷/过喷Dryspray/Overspray •漆膜表面粗糙不平，呈颗粒在表面附着•An uneven film and a rough, sandpaper texture on the surface•这种漆雾附着力极差•Poor adhesion•干喷主要是以下原因造成：•Dryspray caused by：•喷涂距离过远，或涂料干燥太快，高温下施工，喷涂压力过高，强风或通风过度等•Too long spraying distance, drying too fast, too high temperature, too high air pressure , too windy ortoo good ventilation•主要的原因是溶剂还没有到被涂物表面就过早地损失了•The primary cause is that solvent has been lost prematurely not to reach the sprayed object.白化/ 胺起霜Blooming/amine blushing •涂料在完全固化前，有可能会产生发花或白化现象。
冷凝与湿气会在涂层表面形成白点。
•The surface of coatings may be occurring blooming before completely curing and the white spots shall be formed by condensation/moisture.•胺固化的环氧涂料，在较冷或湿润大气环境下进行固化时，胺会与空气中的二氧化碳(CO2)和湿气(H2O)发生反应形成铵盐。
通常我们把这种情况叫做胺起霜或胺白化，其结果就是漆膜发粘，经常呈白色污迹。
•Epoxy paints especially amine cured are particularly subject to poor curing at cold, humid weather conditions. The amines react withcarbon dioxide(CO2)，humidity(H2O) in the air to form an aminecarbamate, commonly referred to as ”amine blooming” or“amine blushing”. The result is a tacky film often appearing aswhite stains.•胺起霜是水溶的，能被干净的温水抹去.。