Tantalum-containing cast nickel-based superalloy for 700 DEG C unit and preparation method thereof

A nickel-based high-temperature alloy and unit technology, applied in the field of heat-resistant alloys, can solve the problems of reducing the uniformity of the alloy structure, affecting the mechanical properties of the alloy, and slowing the diffusion rate, achieving high microhardness at room temperature, improving structure stability, and inhibiting The effect of coarsening

Pending Publication Date: 2022-03-15
INST OF METAL RESEARCH - CHINESE ACAD OF SCI
View PDF0 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Ta is an effective solid solution strengthening element, which can improve the strength of the alloy matrix; it is also a forming element of the γ' strengthening phase, which can effectively enhance the precipitation strengthening effect of the γ' phase; it is also a strong forming element of MC carbide, and MC carbide The material has good stability, thereby improving the stability of the structure; in addition, it can also reduce the tendency of freckles in the casting process, and significantly improve the casting performance of superalloys; The solid solubility in superalloys is limited, the diffusion rate is slow, and serious element segregation is prone to occur during solidification, and large MC-type carbides are formed. Therefore, excessive Ta elements will reduce the uniformity of the alloy structure and affect The mechanical properties of the alloy; therefore, the main γ' phase forming elements Al and Ti, as well as the reasonable element ratio and composition range of Ta elements can effectively improve the microstructure stability of nickel-based superalloys for long-term high-temperature service

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Tantalum-containing cast nickel-based superalloy for 700 DEG C unit and preparation method thereof
  • Tantalum-containing cast nickel-based superalloy for 700 DEG C unit and preparation method thereof
  • Tantalum-containing cast nickel-based superalloy for 700 DEG C unit and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0046] Prepare raw materials according to the set composition; raw materials contain Ta 0.49%, Cr 22.21%, Co 12.00%, Mo 8.55%, Al 1.2%, Ti 0.34%, Al+Ti=1.54%, C 0.044%, B 0.004% by mass percentage , the balance being Ni, (Al+Ti) / Ta=1.54 / 0.49=3.14≥0.8; and Ti / Al=0.34 / 1.2=0.28≤0.8;

[0047] Put the raw materials into a vacuum induction furnace and melt under vacuum conditions; the melting temperature is 1530±25°C;

[0048] Refining and removing impurities of the smelted material under vacuum conditions, and then casting wax molds under vacuum conditions; the pouring temperature is 1460±25°C;

[0049] After the pouring is completed, keep the vacuum condition until the molten steel conjunctiva is released from the furnace, and then cooled to room temperature to make an ingot;

[0050] The as-cast microstructure of the ingot is as follows: figure 1 As shown in the figure, it can be seen that the structure is mainly composed of typical dendrites, in which the secondary dendrite sp...

Embodiment 2

[0060] Method is with embodiment 1, and difference is:

[0061] (1) The raw material contains Ta 0.5%, Cr 20.5%, Co 11.4%, Mo 8.5%, Al 1.15%, Ti 0.36%, Al+Ti=1.51%, C 0.057%, B 0.003%, and the balance is Ni, (Al+Ti) / Ta=1.51 / 0.5=3.02≥0.8; and Ti / Al=0.36 / 1.15=0.31≤0.8;

[0062] (2) Solid solution treatment is carried out when the temperature drops to 1200°C, and the time is 1.5h;

[0063] (3) Tensile strength at room temperature σ of cast nickel-base superalloy containing tantalum b 581MPa, yield strength σ 0.2 It is 269MPa, the elongation at break is 49%, and the reduction of area is 52%; the tensile strength σ at 700±1°C b 385MPa, yield strength σ 0.2 It is 138MPa, the elongation at break is 56%, and the reduction of area is 49%.

Embodiment 3

[0065] Method is with embodiment 1, and difference is:

[0066] (1) The raw material contains Ta 1.89%, Cr 22.5%, Co 12%, Mo 8.4%, Al 1.25%, Ti 0.34%, Al+Ti=1.59%, C 0.05%, B 0.004%, and the balance is Ni, (Al+Ti) / Ta=1.59 / 1.89=0.84≥0.8; and Ti / Al=0.34 / 1.25=0.272≤0.8;

[0067] (2) When the temperature drops to 1150°C, solid solution treatment is carried out for 2 hours;

[0068] (3) Tensile strength at room temperature σ of cast nickel-base superalloy containing tantalum b 590MPa, yield strength σ 0.2 It is 272MPa, the elongation at break is 47-51%, and the reduction of area is 55%; the tensile strength σ at 700±1°C b 390MPa, yield strength σ 0.2 It is 139MPa, the elongation at break is 60%, and the reduction of area is 49%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
tensile strengthaaaaaaaaaa
yield strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a tantalum-containing cast nickel-based high-temperature alloy for a 700 DEG C unit and a preparation method thereof. The alloy comprises the following components in percentage by mass: 0.2-2.0% of Ta, 20-23% of Cr, 11-13% of Co, 8-9% of Mo, 1.2-2.4% of Al + Ti, less than or equal to 1% of Nb, less than or equal to 0.06% of C, less than or equal to 0.004% of B and the balance of Ni. The method comprises the following steps: (1) preparing raw materials according to set components; (2) smelting under a vacuum condition; (3) refining and removing impurities, and then carrying out vacuum pouring; (4) keeping the vacuum condition until the molten steel forms a film, and discharging to prepare a cast ingot; and (5) preserving heat at 1150-1200 DEG C for 1-2 hours, carrying out solution treatment, and carrying out water cooling. According to the invention, the strength of the solid solution is ensured by utilizing the matching of several elements including the Ta element, meanwhile, a more stable precipitated phase is formed, the coarsening of a grain boundary is inhibited, and meanwhile, the optimal chemical component range, the optimal element adding proportion and the optimal heat treatment process system are determined.

Description

technical field [0001] The invention belongs to the technical field of heat-resistant alloys, in particular to a tantalum-containing cast nickel-based superalloy for a 700°C unit and a preparation method thereof. Background technique [0002] Due to their excellent high-temperature mechanical properties, thermal corrosion resistance and good long-term structural stability, superalloys have become indispensable materials for core hot-end components in nuclear energy, thermal power, aviation, aerospace and other industrial fields. The interaction of harsh conditions such as high temperature, corrosion, oxidation, and load. Among them, nickel-based superalloy is the most widely used superalloy, which has excellent oxidation resistance and corrosion resistance. Nickel-based superalloys are generally divided into solid-solution-strengthened and precipitation-strengthened superalloys. The types of elements in the two types of alloys are roughly the same, and the main difference l...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C22C19/05C22C1/02C22F1/10
CPCC22C19/055C22C1/023C22F1/10C22F1/002C21D2211/001C21D2211/004
Inventor 侯介山高双郭永安王常帅秦学智周兰章
Owner INST OF METAL RESEARCH - CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap