| 摘要 |
PURPOSE:To descale a hot rolled austenitic stainless steel sheet at a high speed by subjecting the sheet to mechanical descaling then preheating the sheet to an adequate temp. and pickling the sheet with an aq. soln. contg. nitric acid and hydrofluoric acid prepd. to an adequate concn. CONSTITUTION:The hot rolled sheet or strip of the austenitic stainless steel is subjected to mechanical descaling of a shot blast method, etc. Said steel sheet or strip is then preheated to 40-150 deg.C surface temp. and is thereafter pickled by using the aq. soln. consisting of nitric acid and hydrofluoric acid contg. 100-400g/l NHO3 and 75-400g/l HF. The reaction between the above- mentioned steel sheet or strip is thereby initiated right after the immersion and thereafter the reaction is stably continued, by which the steel sheet or strip is quickly descaled and the excellent surface free from intergranular corrosion is obtd.
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