In the conventional trading of galvanized steel sheets, cold-rolled basic galvanizing is the main method, and hot-rolled substrates are relatively rare. So, what is the difference between hot-rolled substrates and cold-rolled substrates? Let's make a simple interpretation from the following aspects:

1. Cost: Because there is one less process than cold-rolled substrates, the production cost of hot-rolled substrate galvanizing is lower than that of cold-rolled substrates, mainly annealing cost and cold-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 better adhesion, and the coating thickness tends to be 140/140g/m2. However, the thickness size is not as accurate as 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 galvanized steel sheet is not as good as a cold-rolled steel sheet in terms of dimensional accuracy and surface quality, but thicker than a cold-rolled galvanized steel sheet, so it is often used in structural components with low surface requirements but high strength and thickness requirements. Because hot-rolled galvanized steel sheet has low cost, and with the progress of technology, the specification thickness is getting larger and larger, and the usage is gradually increasing.

4. Brand
Common brands of hot-rolled galvanized steel sheet are DD51D+Z, HD340LAD+Z, HR340LA, HR420LA, HR550LA, etc.;
Cold-rolled galvanized steel sheet corresponds to 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, which can generally be considered a hot-rolled galvanized steel sheet.