CN103361546A - Ultra-high strength strapping raw sheet and manufacturing method thereof - Google Patents

Abstract

The invention provides an ultra-high strength strapping raw sheet and a manufacturing method thereof. The raw sheet comprises the following chemical components by weight percent: 0.15-0.60% of C, 0.25-1.80% of Si, 1.0-3.5% of Mn, the balance of Fe and inevitable impurities, wherein one or more of 0.05-1.00% of Cr, 0.05-0.50% of Ni, 0.01-0.50% of Mo, 0.002-0.010% of B, 0.01-0.10% of Ti, 0.01-0.10% of V, and 0.01-0.10% of Nb also can be added to the steel. The manufacturing method of the raw sheet mainly adopts the processes of smelting, casting, hot rolling, pickling and cold rolling; the hot rolling finishing temperature is 850-950 DEG C; the hot-rolling coiling temperature is 550-750 DEG C; and the cold rolling reduction ratio is 50-70%. The tensile strength of the raw sheet disclosed by the invention after the process of isothermal quenching, or quenching and tempering can achieve over 1250 MPa; the extensibility can be up to over 12%; the requirements of wool and cotton packaging on the high strength and high tenacity are met; the section size of the strapping steel is reduced; consumption of steel products is reduced; and the ultra-high strength strapping raw sheet has a broad popularization and application prospect.

Description

The strong tie raw sheet of superelevation and manufacture method thereof

Technical field

The invention belongs to tie and use the rings territory, particularly the strong tie raw sheet of a kind of superelevation and manufacture method thereof.

Background technology

Use the rings territory at tie, in order to improve the service efficiency of steel, guarantee Package Quality, satisfy the requirement of various industries, continually develop out high-strength binding band steel and manufacturing technology thereof, wherein wool, cotton packing etc. are had relatively high expectations to the strength and toughness of tie steel.It is that 0.20%-0.25%, manganese content are that 0.30%-0.60%, boron are the aluminium killed steel of 1.07-1.43 with the ratio of free nitrogen that CN95103707.2 adopts carbon content, 600 ℃ of coiling temperatures, cold rolling draft about 80%, the tie steel tensile strength of making is 880-1090MPa, unit elongation is not more than 4%, and this tie need to carry out zinc-plated processing; It is that 0.22%-0.29%, manganese content are the chill steel band of 1.3%-1.5%, aluminium content 〉=0.015%, content of niobium 〉=0.012% that CN02109635.X adopts carbon content, after 450-550 ℃ of processing, can make the tie steel of tensile strength 〉=920MPa, unit elongation 〉=11%; It is that 0.8%-1.2%, silicone content are that 0.2%-0.4%, titanium content are that 0.025%-0.045%, content of vanadium are the steel of 0.05%-0.07% that US20030034100, CN03104312.7 adopt carbon content＜0.2%, manganese content, finishing temperature is 900 ℃, coiling temperature is 570 ℃, be rolled into 0.8mm through 60% cold rolling draft, be quickly cooled to room temperature after being heated to two-phase region, the tie steel tensile strength of making is 970-1070MPa, unit elongation A ₅₀Be 10-14%; , to adopt carbon content be that 0.15%-0.28%, silicone content are that 0.005%-0.07%, manganese content are the chill steel band of 1.2%-1.7% to CN200410031162.8, after 400-600 ℃ of processing, can make the tie steel of tensile strength 〉=930MPa, unit elongation 〉=8%; It is that 0.11%-0.17%, silicone content are that 0%-0.05%, manganese content are the chill steel band of 0.25%-0.55% that CN200910300597 adopts carbon content, after 380-420 ℃ of processing, can make the tie steel of tensile strength 〉=800MPa, unit elongation 〉=10%; It is that 0.25%-0.42%, silicone content are not more than 0.45%, manganese content is the chill steel band of 1.0%-2.0% that CN200910045451.6 adopts carbon content, after 430-580 ℃ of blue annealing, can make the tie steel of tensile strength 〉=1000MPa; It is that 0.25%-0.35%, Mn content are that 1.0-2.0, Si are not more than 0.4% steel that CN200910046229.8 adopts carbon content, through hot rolling, cold rolling after, adopt the thermal treatment process of ferrite+rapid quenching+tempering of austenite two-phase region, can make the tie steel of tensile strength 〉=1100MPa, unit elongation 〉=10%; US20070235112 provides a kind of cold rolling fully hard matter tie steel and manufacture method thereof, the chemical ingredients of steel is: carbon 0.02%-0.25%, manganese 0.15%-1.5%, aluminium 0.01%-0.12%, nitrogen 0.04%-0.03%, copper 0.04%-0.50%, nickel 0.03%-0.25%, molybdenum 0.02%-0.25%, chromium 0.03%-0.25%, silicon are not more than 0.25%, and tie steel tensile strength is about 900MPa; EP14288295 adopts C-Mn-Si steel lead patenting technique, and production tensile strength is 1170-1240MPa, and unit elongation is 6.5% tie steel; US5542995 adopts that C is 0.56%, the AISI1055 bar of Mn0.70%, is rolled into flat tie, and tensile strength can reach 1170MPa, and unit elongation is 5%, and this technology manufacturing process is complicated, and dimensional precision is difficult to guarantee.

Be summed up, the main production of high-strength binding band steel has four kinds at present: the one, adopt the technique of annealing after the cold rolling reinforcement, and take full advantage of cold rolling work hardening, the tie steel toughness that this technique is made is lower, and it is larger that performance is affected by raw material; The 2nd, the bainite reinforcing process of employing lead patenting, but its equipment is complicated, particularly adopts lead bath to process, and can cause serious environmental pollution, and some countries have limited use; The 3rd, the martensite strengthening technique that adopts two-phase region to quench can adopt water as quenchant, non-environmental-pollution; The 4th, adopt rod hot rolling to become flat material technique.Tensile strength reaches 1250MPa, unit elongation reaches 12% the strong tie steel of superelevation and raw sheet thereof but above-mentioned technology can't be made.

Summary of the invention

The object of the present invention is to provide a kind of tensile strength to reach 1250MPa, unit elongation reaches 12% superstrength tie raw sheet and manufacture method thereof.

1250MPa grade super strength tie raw sheet of the present invention adopts smelting, casting, hot rolling, pickling, cold-rolling process to produce, and smelting can be adopted the variety of way deoxidations such as silicon deoxidation, aluminium deoxidation and aluminium silicon complex deoxidization, it is characterized in that:

A) chemical ingredients of steel is C0.15%-0.60%, Si0.25%-1.80%, Mn1.0%-3.5%, and all the other are iron and inevitable impurity.

B) can also add among 0.05%-1.00%Cr, 0.05%-0.50%Ni, 0.01%-0.50%Mo, 0.002%-0.010%B, 0.01%-0.10%Ti, 0.01%-0.10%V, the 0.01%-0.10%Nb one or more in the steel.

C) hot rolling finishing temperature is 850-950 ℃, and the hot rolling reeling temperature is 550-750 ℃, cold rolling draft 50-70%.

D) strand can adopt the hot-loading and hot-conveying mode to enter stove, and charging temperature is not less than 600 ℃.

Carbon is most economical in the steel, topmost alloying element, and is all very large to final tissue and the intensity effect of steel, can obviously improve hardening capacity and the hardenability of steel.If carbon content is excessively low, when becoming martensite, austenitic transformation can not produce enough distortion to strengthen martensite, the undercapacity of steel plate; But too high carbon content has a negative impact to plasticity, toughness, weldability.Therefore its content range is 0.15%-0.60%.

Manganese is displaced type solution strengthening element, can change austenite transformation temperature, is conducive to obtain tiny phase-change product, improves the hardening capacity of steel, and the content range of manganese is 1.0%-3.5%

Silicon is the solution strengthening element, can change austenite transformation temperature, can also suppress cementite and separate out stable austenite; But too high silicon can make the oxide film of surface of steel plate be difficult to remove, and the content range of silicon is 0.25%-1.80%.

In order to improve hardening capacity, can also add chromium and boron, chromium can also play solution strengthening effect and improve the solidity to corrosion of steel.The scope of chromium and boron is respectively 0.05%-1.00% and 0.002%-0.010%.

Effect and the manganese of nickel are similar, can improve in addition the corrosion resisting property of tie steel, but the price of nickel element are higher, and its content range is 0.05%-0.50%.

The adding of molybdenum can improve hardening capacity, improves simultaneously the stability of steel, and its content range is 0.01%-0.50%.

Titanium, vanadium, niobium mainly play the effect of crystal grain thinning and precipitation strength, and its content range is 0.01%-0.10%.

The invention provides a kind of tensile strength and reach 1250MPa, unit elongation reaches 12% superstrength tie raw sheet and manufacture method thereof, this steel after heat treatment can satisfy wool, cotton is packed to the demand of high strength, high tenacity, reduce tie steel sectional dimension, reduce steel consumption, have wide popularizing application prospect.

Embodiment

1250MPa grade super strength tie raw sheet of the present invention adopts smelting, casting, hot rolling, pickling, cold-rolling process production, and its chemical ingredients is as shown in table 1, and manufacturing process is as shown in table 2.The chemical ingredients of sequence number 1～3 is not corresponding with the technique of sequence number 1 in the table 2 in the table 1; The chemical ingredients of sequence number 4～6 is not corresponding with the technique of sequence number 2 in the table 2 in the table 1; The chemical ingredients of sequence number 7～9 is not corresponding with the technique of sequence number 3 in the table 2 in the table 1; Sequence number 10 in the table 1,11 chemical ingredients are not corresponding with the technique of sequence number 4 in the table 2; Sequence number 12 in the table 1,13 chemical ingredients are not corresponding with the technique of sequence number 5 in the table 2; Sequence number 14 in the table 1,15 chemical ingredients are not corresponding with the technique of sequence number 6 in the table 2.

Table 1 chemical ingredients, wt%

Sequence number	C	Si	Mn	Cr	Ni	Mo	B	Ti	V	Nb
											1	0.15	1	2.5
2	0.25	1.8	2
											3	0.35	1.5	2
4	0.45	0.5	2
											5	0.45	1	1	0.2						0.04
6	0.60	0.25	1.5
											7	0.30	0.50	3.5
8	0.15	1	2.5	0.5	0.2
											9	0.25	1	1.8	0.05	0.05	0.01		0.01		0.01
10	0.15	1	2.5	0.5	0.2	0.2
											11	0.15	1	2.5	0.5	0.2		0.01
12	0.25	1.6	2					0.1
											13	0.25	1.6	2						0.1
14	0.25	1.6	2							0.1
											15	0.25	1.6	2	0.1	0.1	0.1	0.002	0.02	0.02	0.02

Table 2 main technologic parameters

Sequence number	Charging temperature, ℃	Final rolling temperature ℃	Coiling temperature ℃	Cold rolling draft, %
					1		950	650	55
2		900	700	60
					3		850	600	65
4	800	850	550	50
					5	700	900	750	70
6	600	950	650	55

According to the tie steel raw sheet that table 1, table 2 are made, be heated to the above temperature of two-phase region and keep for some time, its tensile strength can reach more than the 1250MPa behind isothermal quenching or quenching+tempering, and unit elongation can reach more than 12%.

Claims (4)

1. strong tie raw sheet of superelevation is characterized in that the weight percent of the chemical ingredients of steel is: C0.15%-0.60%, Si0.25%-1.80%, Mn1.0%-3.5%, all the other are iron and inevitable impurity.

2. the strong tie raw sheet of superelevation according to claim 1 is characterized in that adding in the steel among 0.05%-1.00%Cr, 0.05%-0.50%Ni, 0.01%-0.50%Mo, 0.002%-0.010%B, 0.01%-0.10%Ti, 0.01%-0.10%V, the 0.01%-0.10%Nb one or more.

3. one kind is used for claim 1 or the former board fabrication method of 2 described superstrength ties, main smelting, casting, hot rolling, pickling, the cold-rolling process of adopting, it is characterized in that: hot rolling finishing temperature is 850-950 ℃, and the hot rolling reeling temperature is 550-750 ℃, cold rolling draft 50%-70%.

4. the former board fabrication method of superstrength tie according to claim 3 is characterized in that: strand adopts the hot-loading and hot-conveying mode to enter stove, and charging temperature is not less than 600 ℃.