Steel characteristics: the surface gloss of 304d and 304 stainless steel welded pipes (measured at an angle of 60 degrees) is very high, around 510, of which the surface gloss of 304d is slightly better than 304. Mechanism: the surface gloss and hardness of stainless steel welded pipes are strong Related. In general, the higher the hardness of the welded pipe, the better the gloss of the polishing, and the easier it is to polish. The hardness of 304d stainless steel welded pipe is about 230hv, and that of 304 stainless steel is about 175hv. The hardness of the 304d welded pipe is significantly higher than 304, so polishing is more time-saving and easier to polish. The development direction of decorative welded pipes is to maintain the good corrosion resistance of 304 stainless steel. Implement high reinforcement. Aod refined 304, widely used in the market, has good corrosion resistance but low strength. Especially for the thin-gauge 304 welded pipe, if it is accidentally transported or used, it may be deformed when it encounters external forces, and it will seriously affect delivery and use. The strength of 200 series stainless steel is higher than that of 304, but the corrosion resistance is very poor, and the corrosion failure will not occur soon. What users dream of is a good material that combines corrosion resistance and high strength. 304d stainless steel just came into being, which meets the needs of the market in both corrosion resistance and high strength. It can completely replace 304, and its comprehensive cost performance is better than 304.