Pickling solution for removing hot-rolled double-phase stainless steel oxide skin and pickling method of pickling solution

Abstract

The invention provides a pickling solution for removing hot-rolled double-phase stainless steel oxide skin and a pickling method of the pickling solution, and the picking solution can be used for quickly removing the iron oxide skin on the surface of a hot-rolled double-phase stainless steel strip better. The picking method comprises the following steps: preparing the pickling solution by sequentially mixing hydrochloric acid, nitric acid and hydrofluoric acid to obtain a mixture, and standing the mixture for about half an hour after lightly mixing the mixture for about 1-2 minutes, wherein the pickling solution consists of the following components in parts by mass: 2-3 parts of hydrochloric acid with concentration being 36%-38%, 1 part of nitric acid with the concentration being 65%-68%, and not less than 1 part of hydrofluoric acid with the concentration being 40%; completely soaking a hot-rolled double-phase stainless steel sample into the prepared pickling solution for pickling for 20-35 minutes, observing the oxide skin removal condition of a plate surface, and taking out the plate surface when the oxide skin almost drops; and under tap water, clearing the residual iron oxide skin attached to the plate surface by use of a banister brush, then, flushing the plate surface for 1-2 minutes by use of hot water, quickly blow-drying the plate surface by use of an air blower, thereby obtaining a pickled solution with better degree of finish.

Description

technical field [0001] The invention relates to a pickling solution for removing scale of hot-rolled duplex stainless steel and a pickling method thereof, which belongs to the technical field of stainless steel surface treatment and is especially suitable for duplex stainless steel 2205, 2101 and 2507. Background technique [0002] Since the advent of duplex stainless steel, due to the performance advantages of both ferritic and austenitic stainless steel, it has excellent mechanical properties, welding properties, and resistance to stress corrosion cracking, especially in chloride ion environments. The combination of these excellent properties makes it widely used in petroleum, chemical, electric power and other fields. However, due to the poor thermal processing performance of duplex stainless steel, there is a tendency to edge cracks and surface cracks during thermal processing. [0003] During the hot rolling or solid solution process of duplex stainless steel, a layer ...

AI Technical Summary

Problems solved by technology

[0004] Check the current open literature and patents, there are some shortcomings in the existing duplex stainless steel pickling solution, for example, the publication number is that CN103820798A is only used for continuous pickling production, and is not suitable for its research field; the publication number is that CN104404551A mentions Use a mixed solution of nitric acid and hydrofluoric acid as pickling solution for stainless steel. The pickling solution has no obvious pickling effect on hot-rolled duplex stainless steel. The pickling solution needs to be heated, and the operation is complicated and the steps are cumbersome.