Hot water acid-resistant enamels for sheet steel

✍ Scribed by A. S. Kassem; M. Z. Mostafa; M. F. Abadir; S. A. El Sherbiny

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: German
• Weight: 176 KB
• Volume: 61
• Category: Article
• ISSN: 0947-5117
• DOI: 10.1002/maco.200805230

✦ Synopsis

Abstract

Several enamel frit recipes were formulated for direct‐on application on sheet steel. Their suitability as hot water and acid‐resistant coatings were investigated. DTA analyses were performed on raw batches to follow up physico‐chemical changes occurring on firing. Then batches with different recipe compositions were fritted and mixed with mill additions. These were then tested for thermal expansion and the corresponding linear coefficients as well as glass transition temperatures and softening points were obtained. Also, the viscosity of molten frits was determined as a function of temperature. These frits were then applied on sheet steel and the following properties were investigated: resistance to hot water, acid resistance, surface gloss, and adherence to steel. It was found that recipe No. 4, containing no manganese dioxide and the highest amount of nickel oxide among all the suggested recipes, gave the best results. The optimum conditions for application on steel sheet were: firing at 850 °C for 5 min.