CN1308144A

CN1308144A - High-performance impact resisting steel

Info

Publication number: CN1308144A
Application number: CN 00136243
Authority: CN
Inventors: 董瀚; 时捷; 王琪
Original assignee: Central Iron and Steel Research Institute
Current assignee: Central Iron and Steel Research Institute
Priority date: 2000-12-25
Filing date: 2000-12-25
Publication date: 2001-08-15
Anticipated expiration: 2020-12-25
Also published as: CN1102671C

Abstract

The present invention belongs to the field of low-alloy steel, in particular it is applicable to production of high-performance high impact-resistance steel which possesses tensile strength range of 1900-2273 MPa as well as good combination property and excellent deep-punching property. The chemial composition of said steel includes: C 0.3-0.6%, Si 0.1-2.3%, Mn 0.2-2.0%, Ni 1.0-4.0%, Zr 0.01-0.1%, RE 0.001-0.05%, P less than or equal to 0.05%, S less than or equal to 0.020%, Al less than or equal to 0.01%, Cu less than or equal to 0.2%, Ca less than or equal to 0.02%, Mo and/or W 0.2-1.5% and V,Nb,Ti and B 0.02-0.6% besides Fe. As compared with existent technology said steel possesses good combination property, high tensile strength, good processing property and excellent deep punching property.

Description

High-performance impact resisting steel

The invention belongs to the low alloy steel field.Be applicable to that mainly making the tensile strength scope is 1900-2273MPa, the high-performance impact resisting steel that has good over-all properties and good deep drawability simultaneously.

Shellproof (thorn) vest, shield, protective helmet and fortune paper money bullet-proof vehicle, all the weight to self has strict requirement, so just requires the hammer strap that uses to have the high impact-resistant grade, also satisfies certain processing performance requirement simultaneously.Not only require used hammer strap to approach for protective helmet with shellproof steel sheet, also requirement will have good deep drawability simultaneously, so that moulding keeps higher lumber recovery smoothly.Also require hammer strap to have good and economic simultaneously.

Domestic hammer strap commonly used all exists certain deficiency as 616 steel, 232 steel helmets with steel, F601 hammer strap at present, lower as 616 hardness of steel, shock resistance is poor, though and F601 hammer strap processing performance is better, but the grade of tensile strength only is the 1700MPa level, has also limited the performance of its shock resistance.And 232 steel helmets of domestic early development steel, though tensile strength can be handled the 2000MPa level theoretically, but after reaching high strength like this, the plasticity and the toughness of steel plate sharply descend, shock resistance is declined to a great extent, use so only be processed into the 1700MPa level at present, and its processing performance and shock resistance are all poor than the F601 hammer strap.

Studies show that both at home and abroad along with the increase of steel plate hardness, shock resistance significantly improves.For this reason, advanced country all is devoted to develop the ultrahigh hardness hammer strap.When the strength grade of hammer strap is the 2000MPa level, utilize the ultrahigh hardness of steel plate to make impacted object produce gross distortion, thus the impact energy that increases the weight of to consume impacted object, and destroy its penetration stability, the shock resistance of steel plate is significantly improved.But the past is in the research process of seeking ultrahigh impact performance steel plate, fail to solve owing to increasing substantially of hardness makes hammer strap toughness always and reduce, the problem that finally causes shock resistance to descend significantly, thus limited the production of 2000MPa level ultrahigh hardness hammer strap.

The clear 60-169654 steel of Japanese Patent is a compound cast steel, difference by the ectonexine alloying element, adjust the wear resistance and the hot strength that improve finished-product material, to satisfy the demand of cylinder buss, can't reach the shock resistance requirement and its intensity and plasticity and toughness are all very low, can not use in the art.Clear 58-123859 steel is the high temperature tool steel, mainly improve the wear resistance and the toughness of steel at the content of the residual austenite of adjusting material by alloying element and thermal treatment process, and this steel requires to add a certain amount of Cu to improve the oxidation-resistance and the creep property of steel, and in this steel, Cu content is strict control.The S that also adds 0.03-0.4% in the steel is arranged again, its objective is the free cutting property that improves steel, but the also toughness of badly damaged steel and plasticity.The intensity of this steel and toughness proportioning extreme difference simultaneously can't satisfy shock resistance at all and require and be not suitable for this area.

The objective of the invention is to propose a kind ofly have under good plasticity and the flexible prerequisite, tensile strength reaches the 2000MPa level, and have premium properties and favorable manufacturability can the very-high performance impact resisting steel.

According to above-mentioned purpose, the technical solution adopted in the present invention is: (1) is design of alloy reasonably, satisfies steel plate mechanical property, hardening capacity, processing performance and economy requirement.(2) satisfy economic purity requirement, the content of control P, S, O, N, H, with the plasticity and the toughness of assurance steel plate, and the requirement of welding and cutting property, the while has also guaranteed the economy of steel plate.(3) be mingled with form by Sization thing in the Ca processing change steel, have good plasticity when improving the shock resistance of steel plate and guaranteeing the Spheroidizing Annealing attitude.(4) add elements such as a small amount of V, Nb, Zr, generate the tiny carbonitride of disperse with refine austenite crystal grain, improve the intensity and the toughness of steel, the S effect in Zr and the steel reduces the harm of S simultaneously, has obviously improved the shock resistance of steel.(5) pass through the diffusion of effect fix N, P, S and the inhibition hydrogen of W, Ti, Mo, thereby improve the plasticity and the toughness of steel.(6) improve the hardening capacity of steel by B, make steel plate under the lower condition of alloy content, guarantee through hardening fully in air.According to foregoing, the concrete chemical ingredients of steel of the present invention (weight %) that we proposed is as follows: C:0.30-0.60%, Si:0.10-2.30%, Mn:0.20-2.00%, P :≤0.050%, S :≤0.020%, Cr:0.10-2.00%, Mo and W add wherein any one and two kinds of sum: 0.20-1.50%, Ni:1.00-4.00%, Zr:0.01-0.10%, V, Nb, Ti, must add wherein a kind of among the B and other three kinds in the content of arbitrary element sum be: 0.02-0.60%, RE 0.001-0.05 0%, Al :≤0.01%, Cu :≤0.20%, Ca≤0.02%, all the other are Fe.

The effect of each element and proportioning are according to as follows:

C: quench, after the tempering in order to obtain required high strength, C content must be more than 0.30%, but too much C content can worsen the plasticity and the toughness of steel, and the processing performance of steel, thereby C content is controlled to be 0.30-0.60%.

Si: when content is controlled at 0.10-0.40%, mainly be to be used for reductor.But add 1～2.3%Si in steel tempered martensite fragility low ebb is moved to the high temperature direction, the carbon martensite steel can be in the mesophilic range tempering in making, this moment intensity and not obvious decline, and plasticity and toughness have raising by a relatively large margin.Si does not postpone the formation of εTan Huawu, but to Fe ₃C is formed with inhibition.The precipitation of εTan Huawu is little to the weakening of intensity, but Fe ₃The formation of C and first kind temper brittleness have confidential relation.

Mn:Mn is the effective element of deoxidation, can also improve the hardening capacity and the intensity of steel, but during the Mn too high levels, the tendency that makes the crystalline grain of steel alligatoring is arranged, and increases the crisp susceptibility of tempering of steel, thereby control Mn content is below 2.00%.

P:P can form microsegregation when solidification of molten steel, gather partially at crystal boundary when austenitizing temperature heats subsequently, and the fragility of steel is enlarged markedly, so the content of control P is below 0.050%.

S: inevitable impurity, formation MnS are mingled with and can worsen the plasticity and the toughness reduction of steel at grain boundary segregation, thereby control its content below 0.020%.

Cr: can improve the hardening capacity and the resistance to tempering of steel effectively, to obtain required high strength.Content is difficult to function as described above less than 0.50%, but content surpasses 2.0% toughness and cold-workability that can worsen steel.

Ni: the effect of solution strengthening is arranged, but most importantly improve the toughness of steel, especially low-temperature flexibility is had good effect.

Mo and W: when improving the hardening capacity of steel and resistance to tempering effectively, can also strengthen crystal boundary, reduce temper brittleness.Content is difficult to function as described above less than 0.20%, but content is saturated above 1.50% above-mentioned action effect, and cost is higher.

V: can crystal grain thinning, improve the grain coarsening temperature, thereby reduce the superheated susceptivity of steel, and further improve the intensity and the toughness of steel.V content then is difficult to function as described above very little, but content effect above 0.40% is saturated.

Al: deoxidation and crystal grain thinning effectively, content does not have above-mentioned effect less than 0.005%, but content effect above 0.10% is saturated, and the thick alumina inclusion that forms can worsen the toughness of steel.

Nb: the toughness effect of crystal grain thinning and raising steel is arranged, but content effect above 0.10% is saturated.

Zr: the austenite crystal of energy refinement steel, can be combined to ZrS with S, prevent the red brittleness of steel.Zr can also improve the low-temperature flexibility of steel, but the solubleness of Zr in steel is very little, and costs an arm and a leg, and general content is no more than 0.10%.

Ti: except that the effect of crystal grain thinning, precipitation strength and fix N, S, the TiC that disperse is separated out is the highest hydrogen trap of trap energy in the steel, can capture hydrogen and make it be evenly dispersed in intracrystalline, suppresses the diffusion of hydrogen, thereby improves the plasticity and the toughness of steel.Ti content does not have above-mentioned effect less than 0.005%, but content effect above 0.10% is saturated.

The main application of B:B in steel is the hardening capacity that increases steel, thereby saves other more valuable alloying elements, as Ni, Cr, Mo etc.

Ca:Ca can change the form of the sulfide inclusion in the steel, makes it the effect of nodularization, and its content should be controlled at below 0.020%.

RE: deoxidization desulfuration is arranged and to the effect of non-metallic inclusion denaturing treatment with reduce hydrogen and other harmful element poly-partially on crystal boundary, the grain-boundary strength of raising steel.RE content does not have above-mentioned effect less than 0.001%, but content surpasses 0.05 0%, then because inclusion increases, worsens the structure property of steel on the contrary.Control its content at 0.001-0.050%.

Steel of the present invention can adopt electric arc furnace, induction furnace, vacuum induction furnace smelting, is cast into steel ingot or continuous casting becomes base, is rolled into plate product through 950-1250 ℃, anneals then.Steel plate carries out 150-300 ℃ of temper then in quench (but air quenching, oil quenching and shrend) behind 800-1150 ℃ of austenitizing.

Impact resisting steel of the present invention is compared with the prior art steel grade and is had good intensity and toughness proportioning, and the maximum tensile strength is 2273MPa, and being far longer than at present, used tensile strength is the hammer strap of 1700MPa.Its armour-piercing mechanism makes the impacted object gross distortion by the theory transition that the plastic deformation ability of former 1700MPa level hammer strap by steel plate consumes the impacted object energy to the ultrahigh hardness that utilizes steel plate, thereby the serious consumption and the interference impacted object penetration stability that cause the impacted object energy, compare steel of the present invention with present used hammer strap shock resistance good comprehensive performances is not only arranged, and tensile strength reaches more than the 2200Mpa, also has good deep drawability and favorable manufacturability energy simultaneously.

Embodiment

Adopt alloy ingredient scope of the present invention to smelt the alloy of 10 kinds of compositions altogether, sequence number 1-10 is an alloy ingredient of the present invention in table 1, wherein sequence number is for 1,2,3,4,5, No. 6 to adopt the 200kg vacuum induction furnace smelting, sequence number is for 7,8,9, No. 10 to adopt 50 tons of electric furnaces+external refining to smelt, for contrasting conveniently, we have smelted the most close impact resisting steel material of three stoves simultaneously, and its sequence number is 11,12,13.Steel ingot of the present invention carries out anneal at 1100 ℃ after being rolled into sheet material again, and Heat Treatment Of Steel of the present invention is to adopt oil quenching after 900 ℃ of insulations, carries out 200 ℃ of temper then.Its performance sees Table 2.In the embodiments of the invention contrast, table 1 is the composition contrast of the embodiment of the invention and prior art steel.Table 2 is the tempered contrast of handling the back mechanical property of the embodiment of the invention and compared steel.Sequence number 1-10 is a steel of the present invention in table 1 table 2, and sequence number 11 is 232 impact resisting steels, and sequence number 12 is 616 impact resisting steels, and sequence number 13 is the F601 impact resisting steel, and sequence number 14 is the clear 60-169654 cast steel of Japanese Patent, and sequence number 15 is the clear 58-123859 steel of Japanese Patent.Has good plasticity and toughness when can find out that by contrast steel of the present invention has ultrahigh hardness again, can guarantee that steel plate of the present invention not avalanche and steel plate under impacted object impacts do not produce entire crack in the impact of impacted object repeatedly, can effectively reduce behind the hammer strap in the suffered surging force of face upholder.Steel of the present invention in addition is in mechanical workout, and welding, flame cutting and cold plastic deformation all are better than the prior art steel.

Table 1 embodiment of the invention and prior art steel constitution contrast (weight %)

Steel grade	Numbering	????C	????Si	????Mn	????Cr	??Ni	????Mo	????P	????S	????Zr	????Nb	????V	????W	????RE	????Ti	????B	????Fe
Steel grade	Numbering	????C	????Si	????Mn	????Cr	??Ni	????Mo	????P	????S	????Zr	????Nb	????V	????W	????RE	????Ti	????B	????Fe	Impact resisting steel of the present invention	??1	??0.32	????0.20	????0.73	????0.54	??1.64	??0.40	????0.010	????0.008	????0.05	??0.09	????-	??-	??-	????-	????-	Surplus
??2	??0.35	????0.14	????0.82	????1.34	??3.46	??0.32	????0.010	????0.005	????0.02	??-	????-	??0.61	??0.004	????-	????-	Surplus			??1	??0.32	????0.20	????0.73	????0.54	??1.64	??0.40	????0.010	????0.008	????0.05	??0.09	????-	??-	??-	????-	????-	Surplus
??2	??0.35	????0.14	????0.82	????1.34	??3.46	??0.32	????0.010	????0.005	????0.02	??-	????-	??0.61	??0.004	????-	????-	Surplus	??3		??0.38	????1.42	????0.89	????1.24	??1.23	??0.28	????0.012	????0.005	????0.05	??0.07	????0.09	??-	??-	????-	????0.003	Surplus
????4	??0.39	????1.42	????0.80	????0.94	??1.19	??0.36	????0.009	????0.006	????0.06	??-	????0.17	??-	??0.009	????-	????-	Surplus	??3		??0.38	????1.42	????0.89	????1.24	??1.23	??0.28	????0.012	????0.005	????0.05	??0.07	????0.09	??-	??-	????-	????0.003	Surplus
????4	??0.39	????1.42	????0.80	????0.94	??1.19	??0.36	????0.009	????0.006	????0.06	??-	????0.17	??-	??0.009	????-	????-	Surplus	??5		??0.44	????1.41	????0.79	????0.95	??1.23	??0.35	????0.010	????0.007	????0.04	??-	????-	??-	??-	????0.08	????-	Surplus
????6	??0.52	????0.23	????0.49	????0.88	??1.54	??0.28	????0.009	????0.005	????0.09	??0.20	????-	??-	??-	????-	????-	Surplus	??5		??0.44	????1.41	????0.79	????0.95	??1.23	??0.35	????0.010	????0.007	????0.04	??-	????-	??-	??-	????0.08	????-	Surplus
????6	??0.52	????0.23	????0.49	????0.88	??1.54	??0.28	????0.009	????0.005	????0.09	??0.20	????-	??-	??-	????-	????-	Surplus	??7		??0.45	????0.27	????0.38	????0.94	??1.44	??0.32	????0.005	????0.002	????0.07	??-	????0.07	??-	??-	????-	????-	Surplus
??8	??0.43	????0.22	????0.43	????0.83	??1.42	??0.26	????0.005	????0.005	????0.10	??-	????0.12	??-	??-	????0.02	????-	Surplus	??7		??0.45	????0.27	????0.38	????0.94	??1.44	??0.32	????0.005	????0.002	????0.07	??-	????0.07	??-	??-	????-	????-	Surplus
??8	??0.43	????0.22	????0.43	????0.83	??1.42	??0.26	????0.005	????0.005	????0.10	??-	????0.12	??-	??-	????0.02	????-	Surplus	??9		??0.47	????1.23	????0.39	????0.82	??1.39	??-	????0.005	????0.005	????0.03	??-	????0.12	??0.78	??-	????0.04	????-	Surplus
??10	??0.43	????0.25	????0.44	????0.33	??0.42	??0.27	????0.010	????0.005	????0.07	??0.05	????0.11	??-	??-	????0.03	????0.005	Surplus	??9		??0.47	????1.23	????0.39	????0.82	??1.39	??-	????0.005	????0.005	????0.03	??-	????0.12	??0.78	??-	????0.04	????-	Surplus
??10	??0.43	????0.25	????0.44	????0.33	??0.42	??0.27	????0.010	????0.005	????0.07	??0.05	????0.11	??-	??-	????0.03	????0.005	Surplus	The contrast steel grade		??11	??0.40	????1.40	????0.90	????1.10	??0.42	??0.40	????0.018	????0.015	????-	??-	????-	??-	??0.08	????-	????-	Surplus
??12	??0.23	????0.85	????1.75	????-	??-	??-	????0.013	????0.009	????-	??-	????-	??-	??-	????0.05	????0.0027	Surplus			??11	??0.40	????1.40	????0.90	????1.10	??0.42	??0.40	????0.018	????0.015	????-	??-	????-	??-	??0.08	????-	????-	Surplus
??12	??0.23	????0.85	????1.75	????-	??-	??-	????0.013	????0.009	????-	??-	????-	??-	??-	????0.05	????0.0027	Surplus		??13	??0.29	????0.33	????0.90	????0.91	??1.18	??0.31	????0.010	????0.005	????-	??-	????-	??-	??-	????-	????-	Surplus

Table 2 embodiment of the invention and the contrast of prior art mechanical property

Steel grade	Numbering	Tempering temperature ℃	??σ _b??MPa	??σ _0.2??MPa	????δ ????％	????ψ ????％	Akv(-40 ??℃) ????J	??HRC
Steel grade	Numbering	Tempering temperature ℃	??σ _b??MPa	??σ _0.2??MPa	????δ ????％	????ψ ????％	Akv(-40 ??℃) ????J	??HRC	Hammer strap of the present invention	????1	??200	??1900	??1505	????13	????55	????22	????53
????2	??200	??1956	??1503	????15	????63	????26	????53			????1	??200	??1900	??1505	????13	????55	????22	????53
????2	??200	??1956	??1503	????15	????63	????26	????53	????3		??200	??2020	??1525	????12	????53	????20	????54
????4	??200	??2040	??1543	????11	????48	????17	????54	????3		??200	??2020	??1525	????12	????53	????20	????54
????4	??200	??2040	??1543	????11	????48	????17	????54	????5		??200	??2060	??1552	????11	????45	????17	????55
????6	??200	??2273	??1868	????8	????42	????12	????57	????5		??200	??2060	??1552	????11	????45	????17	????55
????6	??200	??2273	??1868	????8	????42	????12	????57	????7		??200	??2070	??1559	????12	????53	????19	????55
????8	??200	??2010	??1510	????12	????54	????16	????54	????7		??200	??2070	??1559	????12	????53	????19	????55
????8	??200	??2010	??1510	????12	????54	????16	????54	????9		??200	??2125	??1710	????10	????43	????14	????56
????10	??200	??2050	??1530	????10	????44	????12	????54	????9		??200	??2125	??1710	????10	????43	????14	????56
????10	??200	??2050	??1530	????10	????44	????12	????54	The contrast steel grade		????11	??230	??1764	??1426	????7	????40	????-	????51
????12	??200	??1400	??1100	????10	????46	????12	????40			????11	??230	??1764	??1426	????7	????40	????-	????51
????12	??200	??1400	??1100	????10	????46	????12	????40		????13	??200	??1710	??1440	????12	????58	????9	????50
????14	???-	??223	??-	????0.45	????-	????-	????-		????13	??200	??1710	??1440	????12	????58	????9	????50
????14	???-	??223	??-	????0.45	????-	????-	????-		????15	??400	??-	??-	????-	????-	????5	????45

Claims

1, a kind of high-performance impact resisting steel is characterized in that the concrete Chemical Composition of this steel is (weight %) C 0.3-0.6%, Si 0.1-2.3%, Mn 0.2-2.0%, Ni 1.0-4.0%, Zr 0.01-0.1%, RE0.001-0.050%, P≤0.05%, S≤0.02%, Al≤0.01%, Cu≤0.2%, Ca≤0.02%, any one is 0.2-1.5% with two kinds of sums among Mo and the W, any one and two kinds of sums are 0.02-0.6% among V, Nb, Ti, the B, and all the other are Fe.

2, according to the described alloy of claim 1, any one is 0.20-1.50% with two kinds of element sums among the Mo kind W that it is characterized in that adding in this alloy ingredient.

3, according to the described alloy of claim 1, must add wherein a kind of among V, the Nb that it is characterized in that in this alloy ingredient, adding, Ti, the B and other three kinds in the arbitrary element sum be 0.02-0.60%.