What is the difference between hot-rolled galvanized steel sheets and cold-rolled galvanized steel sheets

1. Cost

Because there is one less process than cold-rolled substrate, the production cost of hot-rolled substrate galvanizing is lower than that of cold-rolled substrate, mainly the annealing cost and cold-rolling rolling cost, and the other processes are similar.

2. Quality performance

Because the hot-rolled substrate is only pickled and annealed to remove surface impurities, its surface is relatively rough, the zinc layer has good adhesion, and the coating thickness tends to be 140/140g/m2. However, the thickness size is not as accurate as that of cold rolling. Since most of them are thick zinc layers, the zinc layer thickness control is also uneven. There is not much difference in mechanical properties, and some properties are even better than cold rolling.

3. Application field

Hot-rolled substrate galvanized steel sheet is not as good as cold-rolled substrate in dimensional accuracy and surface quality, but thicker than cold-rolled galvanized steel sheet, so it is often used in structural components with low surface requirements but high strength and thickness requirements. For example, structural parts of home appliances such as washing machines and refrigerators, internal structural parts of automobiles, structural parts of automobile chassis, passenger car bodies, roofs, highway guardrails, cold-bent steel, etc. Because the cost of hot-rolled galvanized steel sheets is low, and with the progress of technology, the thickness of specifications is getting larger and larger, and the usage is gradually increasing.

4. Brand

The common brands of hot-rolled galvanized steel sheet are DD51D+Z, HD340LAD+Z, HR340LA, HR420LA, HR550LA, etc.;

The corresponding brands of cold-rolled galvanized steel sheet are DC51D+Z, HC340LAD+Z, HC340LA, HC420LA, HC550LA, etc.;

There is also a brand that does not specify whether it is a cold-rolled or hot-rolled substrate, such as DX51D+Z. Generally, this brand can be considered as a hot-rolled galvanized steel sheet.