While most stainless steel applications function exactly as the designer intended, there are times when this most durable of materials fails to meet the high expectations of the consumer. Normally the causes of these issues are pretty straightforward and, with a little foreknowledge, can be easily prevented. Here a few tips on ensuring you get the best of out of stainless steels.
Typical issues with stainless steel
Problems with stainless steel normally arise because of the long supply chain and manufacturing process that the material goes through. Issues can occur at several key points so it is useful to have some knowledge of the stages involved. The main factors to consider during the process are:
Surface finish
While selecting a grade of stainless steel is commonly recognised as an important step in the process, getting the right surface finish is just as crucial. A polished surface finish will give the best resistance to corrosion. In most harsh environments, coastal and dense urban areas for instance, a polish equivalent to the EN 10088-2 2K (Ra = 0.5 micron maximum), normally made using silicon carbide abrasives, will give sufficient corrosion resistance.
Common surface finishes using 240 grit alumina abrasives give surface roughness Ra values of above one micron. This is not enough to prevent corrosion in some tough environments. Architectural drawings without a specific surface finish can be the cause of major problems in the future. Specialist advice on surface finish should be sought if there are any doubts.
Post fabrication treatments
Because welds in stainless steel almost always produce heat tint (an oxidised surface with a reduced resistance to corrosion compared to its parent metal), post weld treatment is essential. Any good fabrication of stainless steel should always include this process.
不锈钢展-2014第十五届广州国际不锈钢工业展-效果最好的不锈钢展会-The 15th China(Guangzhou)Int''l Stainless Steel Industry Exhibition
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