Steel for seamless tin and manufacturing method thereof

Abstract

The invention relates to steel for two piece can and a manufacturing method thereof, the proportion by weight percent of the steel is that: 0.001%<=C<=0.003%; Si<=0.02%, 0.1%<=Mn<=1.0%, P<=0.015%, S<=0.020%, Al<=0.1%, N<=0.005%, the proportion also comprises at least one of four elements: Nb<=0.01%, Ti<=0.01%, Cr<=0.02%, Ni<=0.02%, the rests are Fe and unavoidable impurities. The manufacturing method comprises the steps of: 1) smelting according to above ingredients to cast into the billet; 2) heating and rolling the billet in the range from 1100 to 1250 DEG C, finally rolling the billet in single phase austenite area at the temperature over Ar<3>, the thickness of hot rolling plate is less than 3mm, the coiling temperature is 500 to 700 DEG C; 3) cool-rolling the billet with deflection of 80-95% after pickling; 4) performing recrystallization annealing to the billet below the 730 DEG C in the continuous annealing furnace; 5) secondarily cool-rolling with the deflection of 2-10% to obtain the product having the thickness less than 0.24mm. The steel of the invention includes outstanding processing performance and deep draw performance.

Description

technical field [0001] The invention relates to a steel plate or steel strip for two-piece cans and a manufacturing method thereof, in particular to an ultra-thin steel plate or steel strip for two-piece cans requiring good deep drawing performance and processing performance and a manufacturing method thereof. Background technique [0002] Steel sheets for cans, such as tin-plated steel sheets made of tin-plated steel sheets and tin-free steel sheets treated with chromic acid, are widely used in the manufacture of food cans and pop cans. Such cans can be mainly divided into two-piece cans and three-piece cans. [0003] Two-piece cans usually consist of a bottom, a thin wall body and a lid. Due to the low manufacturing cost, the proportion of two-piece cans in the total cans has increased year by year in recent years. Two-piece cans need to undergo harsh processing operations such as multi-stage deep drawing or DWI (Drawing and Wall Ironing, that is, drawing and thinning af...

AI Technical Summary

Problems solved by technology

The low elongation and r value of the steel plate for two-piece cans will lead to a decrease in deep drawing performance and processing performance, and a decrease in the yield; while excessive strength will result in a decrease in the formability during the can making process and a decrease in the life of the die, etc.

When the recrystallization temperature is increased, the grain growth becomes extremely easy, and the steel structure becomes coarse. Therefore, when deep drawing is performed, the surface will be rough, the appearance will be resistant, and the yield of cans will be reduced.

In addition, these problems increase the energy consumption and cost in the steel plate production process.