Low-cost extra-deep-drawing-quality cold-rolled galvanized steel strip and preparation method thereof

Abstract

The invention discloses a low-cost extra-deep-drawing-quality cold-rolled galvanized steel strip and a preparation method thereof. The steel strip is prepared from, by mass percent, 0.001% to 0.005% of C, 0.07% to 0.12% of Mn, not larger than 0.012% of S, not larger than 0.012% of P, not larger than 0.03% of Si, 0.010% to 0.060% of Als, not larger than 0.0040% of N, 0.0015% to 0.0030% of B and the balance Fe and inclusion within an allowed range. According to the galvanized steel strip, the reasonable carbon content is controlled to reduce the content of free carbon in steel as much as possible; and meanwhile, a certain amount of boron is added to fix interstitial nitrogen and part of carbon, and therefore the timeliness of an extra-deep-drawing-quality galvanized product can be guaranteed. According to the galvanized steel strip, boron is used for fixing carbon atoms, so that the cost of an alloy material is greatly reduced, meanwhile, the heating temperature and soaking temperature of a galvanization procedure can be greatly reduced, and therefore production difficulty and energy consumption are effectively lowered.

Description

technical field [0001] The invention relates to a galvanized steel strip, in particular to a low-cost ultra-deep drawing grade cold-rolled galvanized steel strip and a preparation method thereof. Background technique [0002] With the progress of the steel industry, the manufacturing of household appliances and other machinery has also developed rapidly. As people's requirements for product processing formability and corrosion resistance are getting higher and higher, the amount of ultra-deep drawing galvanized products is increasing. Big. Especially in industries such as home appliances and automobiles. Since home appliances and automobiles are limited by transportation distance and processing cycle, it is necessary to ensure that there are no interstitial atoms in the steel, so as to ensure the timeliness and formability of the steel. [0003] At present, most ultra-deep drawing galvanized products fix interstitial atoms in steel such as carbon and nitrogen by adding a c...

AI Technical Summary

Problems solved by technology

In this way, due to the high cost of niobium or titanium, the cost of raw materials for ultra-deep drawing galvanized products will be roughly 120-150 yuan / ton (different steelmaking levels cause differences in costs)

In addition to fixing the interstitial atoms, niobium and titanium also have an important role in refining the grains and increasing the recrystallization temperature; this will cause the strip heating temperature and soaking temperature in the subsequent galvanizing process to be generally around 820°C. Even higher; high temperature results in high energy consumption for the production of ultra-deep drawing galvanized products. If there is a problem with the production rhythm and it is easy to cause high-temperature broken belts, resulting in very difficult production

[0004] This will make the overall cost of producing ultra-deep-drawing galvanized products very high, and the production is also very difficult, making the price of ultra-deep-drawing galvanized products on the market much higher than ordinary commercial-grade galvanized products