What are the meanings of 2B and BA on the surface of stainless steel

There are many kinds of surfaces of stainless steel cold-rolled products, among which 2B and BA are the two most important surfaces. What do 2B and BA mean respectively?
       They refer to different categories of cold-rolled surface treatment processes. Among them, the formation of 2B is cold rolling-annealing pickling-levelling, and the formation of BA is cold rolling-bright annealing-levelling. The main difference lies in the annealing process. Different, 2B is annealed and pickled, the surface is oxidized to a certain extent, darker; BA is bright annealed, the surface is not oxidized, and is brighter.
       304 is one of the main members of the stainless steel family, with huge output and circulation, and 304J1, as the "brother" of 304 stainless steel plate, is a copper-containing material of 304. The deep drawing performance is better than 304, and it is mainly used for deep processing. , belongs to the nickel-saving series.
       What is the difference between hot-rolled and cold-rolled 304 stainless steel plates

       Rolling is divided into cold rolling and hot rolling, with recrystallization temperature as the distinguishing point.

Hot rolled sheet
       1. Poor toughness and surface smoothness, lower price;
       2. The temperature of hot rolling is similar to that of forging;
       3. The hot plate is processed by hot rolling, and the surface has oxide skin, and the thickness of the plate has a difference;
       4. The price and application of hot-rolled products are much wider than that of cold-rolled products;
       5. The mechanical properties of hot-rolled steel sheets are far inferior to those of cold processing and inferior to forging processing, but they have better toughness and ductility;
       6. The surface of the hot-rolled plate without electroplating is dark brown;
       7. It can be distinguished from the smoothness of the surface after electroplating, and the smoothness of the hot-rolled plate is low;
cold rolled sheet
       1. Good stretchability and toughness, but more expensive;
       2. The surface of the cold-rolling process has no scale, and the quality is good;
       3. Cold rolling is generally used to produce strips, and its rolling speed is relatively high;
       4. The thickness accuracy of cold rolling is higher than that of hot rolling, and the mechanical properties and surface are above hot rolling;
       5. Due to a certain degree of work hardening, the cold-rolled steel plate has low toughness, but it can achieve a better yield ratio, and is used for cold bending spring sheets and other parts;
       6. Because the yield point of the cold plate is closer to the tensile strength, there is no predictability of danger during use, and accidents are prone to occur when the load exceeds the allowable load
       7. The surface of the cold-rolled plate without electroplating is gray.
       8. The smoothness of the surface of the cold-rolled plate after electroplating is higher than that of the hot-rolled plate.