CN103060616B

CN103060616B - Nickel-base heat-resisting alloy

Info

Publication number: CN103060616B
Application number: CN201210572668.4A
Authority: CN
Inventors: 杨钢; 王鲁; 刘正东; 程世长; 王立民; 林肇杰; 李密
Original assignee: Central Iron and Steel Research Institute
Current assignee: Central Iron and Steel Research Institute
Priority date: 2012-12-25
Filing date: 2012-12-25
Publication date: 2015-01-21
Anticipated expiration: 2032-12-25
Also published as: CN103060616A

Abstract

The invention discloses a nickel-base heat-resisting alloy and belongs to the technical field of heat-resisting alloy. The nickel-base heat-resisting alloy comprises chemical components according to percentage by weight are that 0.02-0.05% of carbon (C); 0.6% in maximum of silicon (Si); manganese (Mn) <= 0.02; sulfur (S) <= 0.02; phosphorus (P) <= 0.02; 19-21% of chromium (Cr); 1-2% of aluminum (Al); 1.5-3.0% of titanium (Ti); 5-10% of molybdenum (Mo); 2-10% of wolfram (W); 0-1.5% of niobium (Nb); 0.002-o.005% of boron (B); 0.05-0.2% of zirconium (Zr) and the balance nickel (N). Compared with the prior art, the nickel-base heat-resisting alloy has the advantages that the content of Mo is adjusted, the W and the microelements the B, the Zr, the Nb are added and the cost is improved hardly, but room-temperature mechanical properties after time effects are all improved remarkably, particularly the high-temperature mechanical property is increased remarkably.

Description

A kind of Refractoloy

Technical field

The invention belongs to refractory alloy technical field, in particular, provide a kind of Refractoloy, the blade material of preparation work in high-temperature fuel gas or steam corrosion environment.

Background technology

In the prior art, be operated in the blade material in high-temperature fuel gas or steam corrosion environment, by the difference of use temperature, mainly contain martensite heat-resistant steel, austenitic heat-resistance steel and superalloy.In recent years, for further the net efficiency of fired power generating unit being brought up to more than 50%, just steam-turbine temperature must be brought up to more than 700 DEG C.The high efficiency extra-supercritical unit of development high-parameters, conventional heat-resisting steel material can not meet the service requirements of 700 DEG C of temperature parameter lower blades, but for nickel-base alloy, because its γ ' precipitation strength at high temperature can maintain its creep strength, make it have good high-temperature behavior, and be successfully applied to the high-temperature component of engine and internal combustion turbine, use temperature reaches more than 900 DEG C.A series of research and devleopment plan has been worked out, in the works all using nickel-base alloy as extra-supercritical unit blade material in the World Developed Countries such as Europe, Japan, U.S. and area for this reason.Along with the fast development of China's extra-supercritical unit and internal combustion turbine, also more and more higher to the performance requriements of material, some modern technique empirical values external in selection obtain our and use for reference.USC141 alloy is that Japan's 700 DEG C of ultra supercritical coal-fired unit research and develop one of calculated alternative blade material.USC141 is at first for the parts of 600 ~ 650 DEG C of steam parameters, and as blade, foundry goods etc., at present for using it for the parts of 700 DEG C of steam parameters, its mechanical property, structure stability need further raising.

Summary of the invention

The object of the present invention is to provide a kind of Refractoloy, with USC141 refractory alloy (a kind of low bulk nickel-base alloy being used as blade and bolt material jointly researched and developed by Hitachi and Hitachi Metals, derive from low expansion alloy Alloy252, its coefficient of expansion is identical with ferritic steel) based on, adjust its principal element composition and add the mechanical property that strengthening element realizes significantly improving after timeliness, its chemical composition is as follows:

Chemical component weight percentage composition of the present invention is: C:0.02 ~ 0.05%, Si:0.6% max, Mn≤0.02,, S≤0.02, P≤0.02, Cr:19 ~ 21%, Al:1 ~ 2%, Ti:1.5 ~ 3.0%, Mo:5 ~ 10%, W:2 ~ 10%, Nb:0 ~ 1.5%, B:0.002 ~ 0.005%, Zr:0.05 ~ 0.2%, Ni: surplus.

Adopt on the basis of USC141 refractory alloy according to above-mentioned purpose the present invention, by adjustment Mo content, and add the alloying elements such as W, Nb, B, Zr, achieve the object significantly improving room, mechanical behavior under high temperature.

Nickel-base alloy adopts solution strengthening, precipitation strength and grain-boundary strengthening three kinds of schedule of reinforcements usually.The technological principle of foregoing invention technical scheme is solution strengthening element W, precipitation-strengthening element Nb and boundary-strengthening element B and Zr.

Use Thermo-calc software to carry out thermodynamic simulation to the amount of precipitation variation tendency of each strengthening phase in alloy after adjustment W and Mo constituent content, calculation result is by shown in Fig. 1,2 and 3.Fig. 1 be adjustment Mo and content of element W on the impact of γ ' phase, as seen from the figure, adjustment Mo content, adds W element, can promote the precipitation of γ ' phase on a small quantity; Fig. 2 is for adjustment Mo and content of element W are to M ₂₃c ₆impact, as seen from the figure, adjustment Mo content, adds W element, can improve M ₂₃c ₆complete solvent temperature, little on the impact of its amount of precipitation; Fig. 3 is for adjustment Mo and content of element W are to M ₆the impact of C, as seen from the figure, adjustment Mo content, adds W element, can promote M ₆the precipitation of C, and improve M ₆the Precipitation Temperature of C.So adjustment Mo content, adds W element, can improve M ₂₃c ₆and M ₆the transition temperature of C, promotes precipitation and the M of γ ' phase ₆the precipitation of C, improves the precipitation strength effect of γ ' phase and the grain-boundary strengthening effect of carbide, comprehensively can improve the mechanical property of material.But W content can not add too much, otherwise easily form harmful phase P phase in During Process of Long-term Operation, lose strengthening effect.

Nb can promote the precipitation of γ ' phase, delays the agglomeration process of γ ' phase, can put forward heavy alloyed hot strength.But Nb has very strong electronegativity, very easily promote the precipitation of TCP phase, and the antioxidant property of Nb heavy losses alloy, the Nb content therefore in superalloy is generally all lower than 3%.

B and Zr is strengthening crystal boundary element, can be adsorbed near crystal boundary and cause part alloying, slow down the diffusion process near crystal boundary and stable crystal boundary Micro Phases form, crystal boundary sheet, born of the same parents' shape precipitated phase can be suppressed and improve the state of the intensive uneven distribution of carbide.And B is at Grain Boundary Segregation, M can be formed in conjunction with the TCP phase forming element of some amount ₃b ₂boride (a kind of gap phase of high temperature alloy), improves microstructure stability, thus favourable to heat resistance.

According to above-mentioned purpose and technological principle technical scheme of the present invention be: on the basis of USC141 refractory alloy chemical composition, adjustment Mo content, add 2 ~ 10%W, 0 ~ 1.5%Nb, 0.002 ~ 0.005%B, 0.05 ~ 0.2%Zr, under identical thermal treatment process, the mechanical property of new alloy after high-temperature aging can significantly improve.

Compared with prior art, adjustment Mo content, add W and micro-B, Zr, Nb, cost improves little, but the room-temperature mechanical property after timeliness is significantly increased, and especially mechanical behavior under high temperature significantly increases in the present invention.

Accompanying drawing explanation

Fig. 1 be adjustment Mo and content of element W on the impact of each strengthening phase, promote the precipitation of γ ' phase.

Fig. 2 be adjustment Mo and content of element W on the impact of each strengthening phase, can M be improved ₂₃c ₆mutual transition temperature.

Fig. 3 be adjustment Mo and content of element W on the impact of each strengthening phase, can M be improved ₆the mutual transition temperature of C.

Embodiment

Embodiment 1:

Testing material is selected on the basis of USC 141 refractory alloy chemical composition standard, adjustment Mo content, add 2 ~ 10%W, 0 ~ 1.5%Nb, 0.002 ~ 0.005%B, 0.05 ~ 0.2%Zr, adopt chemical composition in table 1, other composition outside experiment material Mo and W is all same as the prior art.The room-temperature mechanical property contrast table of embodiment 1 and prior art is in table 2.The present invention has formulated multiple thermal treatment process, and after identical thermal treatment, the room-temperature mechanical property of embodiment 1 all promotes to some extent compared with the room-temperature mechanical property of prior art.In above-mentioned list, sequence number 2-7 is the embodiment of the present invention 1, and sequence number 1 is the steel grade of prior art.

Table 1 uses chemical composition for the embodiment of the present invention 1

Sequence number	C	Si	Mn	S	P	Cr	Ni	Al	Ti	Mo	W	Nb	B	Zr
															1	0.026	0.36	0.40	0.0011	＜0.005	19.89	66.31	1.18	1.60	10.05
2	0.024	0.32	0.43	0.0014	＜0.005	20.03	64.18	1.22	1.64	8.12	4.03
															3	0.025	0.33	0.42	0.0008	＜0.005	19.94	60.84	1.19	1.67	5.20	10.24
4	0.033	0.32	0.40	0.0011	＜0.005	19.96	65.11	1.19	1.65	10.23		1.10
															5	0.026	0.31	0.42	0.0012	＜0.005	20.02	65.06	1.20	1.62	10.21		1.12	0.0025
6	0.028	0.35	0.43	0.0008	＜0.005	19.98	66.12	1.19	1.65	10.15			0.0023	0.089
															7	0.032	0.33	0.41	0.0010	＜0.005	20.08	64.72	1.25	1.64	10.43		1.03	0.0025	0.072

The room-temperature mechanical property contrast table of table 2 embodiment of the present invention 1 and prior art

Embodiment 2:

Testing material is identical with embodiment 1, with the mechanical behavior under high temperature contrast table of prior art in table 3.In above-mentioned list, sequence number 2-7 is the embodiment of the present invention 2, and sequence number 1 is the steel grade of prior art.The present invention through the hot strength of 600 DEG C ~ 800 DEG C of twice solution treatment after twice ageing treatment apparently higher than the hot strength of former technology under corresponding temperature after identical thermal treatment, the hot strength of 700 DEG C is even higher than the hot strength of former technology 600 DEG C, and mechanical behavior under high temperature obtains significant raising.

The room-temperature mechanical property contrast table of table 3 embodiment of the present invention 1 and prior art

Claims

1. a Refractoloy, is characterized in that, chemical component weight percentage composition is:

C:0.024%, Si:0.32%, Mn:0.43%, S:0.0014%, P:< 0.005%, Cr:20.03%, Ni:64.18%, Al:1.22%, Ti:1.64%, Mo:8.12%, W:4.03%, total amount is 100%;

Or C:0.026%, Si:0.31%, Mn:0.42%, S:0.0012%, P:< 0.005%, Cr:20.02%, Ni:65.06%, Al:1.21%, Ti:1.62%, Mo:10.21%, Nb:1.12%, B:0.0025, total amount is 100%;

Or C:0.032%, Si:0.33%, Mn:0.41%, S:0.0010%, P:< 0.005%, Cr:20.08%, Ni:64.72%, Al:1.25%, Ti:1.64%, Mo:10.43%, Nb:1.03%, B:0.0025%, Zr:0.072%, total amount is 100%.