N4 nickel plate selection solution| Ni201 Ultra High Temperature + Ultra Low Carbon Exclusive Zone| 6 types of applications +3 cases + domestic import prices

Published by Engineering Team, Shaanxi Qianyi Tuoda Technology Co., Ltd on 2026-07-27

Rooted in Baoji China Titanium Valley, Shaanxi Qianyi Tuoda Deep ploughing nickel material, Titanium non-standard equipment 12 years, N4 nickel plate, High purity nickel processing field accumulated a large number of chemical, nuclear power, Practical experience in semiconductor projects.A nuclear power plant steam generator support plate project, The drawing marks the selection of N4 nickel plate, that is, Ni201 material., Supplier mistakenly supplies as N6 (Ni200), The ingredients seem similar., But there's a 0.08% difference in carbon content., The applicable temperature range of materials differs by 200℃.Graphite embrittlement of N6 alloy easily occurs in the temperature range of 425-650℃., The nuclear power steam generator operates at 320℃ for a long time, is in that risk zone.Carbon content of N4 nickel plate shall be controlled within 0.02%, No sensitization problems, This is nuclear power., ultra-high temperature reactor, The core reason why N4 nickel plate is often selected for semiconductor target projects.the composition of N4 nickel plate is explain in detail in this paper, material property, Six application scenarios, project case, Market Price and Purchase Avoidance Points, Equipment Engineer, Material purchasing personnel collection reference.

core conclusions: N4 is Ni201, suitable for ultra-low carbon and ultra-high temperature working conditions;N6 can be used as an economical alternative to N4 and is only suitable for operating conditions not exceeding 315℃.When the operating temperature is greater than 315℃, or when the whole heat treatment cannot be performed after the welding of the workpiece is completed, N4 nickel plate is more suitable for selection.

The corresponding national standard of N4 nickel plate is N4, which implements GB/T 5235-2021 standard, American standard UNS number N02201, ASTM brand Nickel 201.Comparison of Main Element Index between N4 and N6 Nickel Materials, Total Ni + Co N4 not less than 99.9%, N6 is not less than 99.5%Carbon element N4 is controlled within 0.02%, and the upper limit of N6 is 0.10%.The composition limits of manganese, iron, sulfur, silicon and copper are consistent.The core difference between the two is the carbon content, 0.08% carbon gap, Bring three material performance changes, N6 will precipitate carbon in the range of 425-650℃, graphitization embrittlement, N4 does not have this sensitization phenomenonN4 can be used stably at about 600℃ for a long time, and N6 can be used at 315℃ for a long time.N4 nickel cobalt purity is higher, can meet the basic threshold of semiconductor high purity materials.

Divide the selection interval from temperature condition, When the operating temperature does not exceed 315℃, N6 can be used., The N6, which costs less, is preferred.In the range of 315 to 425℃, N4 is recommended to avoid sensitization risk;Graphite embrittlement of N6 occurs between 425 ℃ and 650℃, and N4 is preferred in this range.Temperatures above 650 ° C, N4 needs a special process, generally used with nickel-based alloys.Many large nickel equipment can not carry out overall heat treatment after welding, such as nuclear steam generator, semiconductor production equipment, No heat treatment after N6 welding, superimposition sensitization effect of weld stress, Stress corrosion cracking is easy to occurN4 relies on an extremely low carbon content to eliminate the risk of sensitization and to provide stable operation without post-weld heat treatment.In the field of electronic semiconductors, Semiconductor sputtering target requires nickel cobalt purity of 99.995%, Ordinary N6 purity is difficult to meet standards, N4 is the basic material selection of electronic grade nickel materials, High-end scenarios also require 4 N 5 to 5N high purity specifications.

N4 nickel plate six typical application industries and parts, Nuclear power field for steam generator support plate, reactor internals, Adapting to high temperature conditions above 320℃ by virtue of non-sensitizing characteristicsUltra-high temperature reaction equipment, molten sodium hydroxide reactor, adapt to 315℃ above concentrated alkali corrosion environment;Semiconductor industry for sputtering targets, electronic components, high-purity materials can reduce production pollution;Glass bulb and high temperature melting glass equipment, bulb mold, glass stirrer, Can withstand molten glass environment above 1000℃Vacuum equipment, vacuum furnace liner, vacuum valve, low outgassing rate under high temperature vacuum environment;High-purity chemical equipment, high-purity reagent production equipment, low-carbon materials to avoid carbon pollution.According to the statistics of Nickel Cobalt Branch of China Nonferrous Metals Industry Association, The domestic market scale is about CNY 1.2 billion for N4 nickel plate products in 2014, Annual market growth rate of 18%, The nuclear and semiconductor industries together account for 55 to 65 percent of overall N4 demand.

Three real engineering applications.case one, N4 nickel plate support plate for steam generator of nuclear power station, Specifications DN800, Sheet thickness 30mm, The medium is high temperature and high pressure steam, Temperature 320℃, Pressure 15MPa.N6 nickel plate was selected initially, graphitization embrittlement occurred after 1 to 2 years of operation.After replacing N4 nickel plate, strictly control carbon content, no heat treatment after welding, stable operation of equipment for 12 years.The unit price of industrial grade N4 nickel plate is about 240-280 yuan per kilogram.Case 2, semiconductor factory N4 nickel sputtering target, specification Φ 300, thickness 10 mm, plasma sputtering environment, temperature 300 ℃.N6 material has high carbon content, which will bring impurity pollution;Using N4 target, nickel cobalt purity meets 99.95% semiconductor requirements, vacuum melting + precision machining process, high purity target unit price 800-1500 yuan per kilogram.Case 3, molten NaOH reactor N4 composite plate equipment, DN1500, length 3000mm, N4+ Q345R composite plate, medium 400℃ molten alkali.Sensitization embrittlement of N6 composite plate, 4mm N4 plate cladding after modification, The shear strength of composite interface is not lower than 140MPa., The whole equipment has been running stably for 6 years, The total price of the whole set of equipment is 600,000 - 850,000 yuan.

N4 sheet production process strict carbon control, Vacuum smelting process required, Material cold work hardening tendency is obvious, The cold forming process requires an intermediate annealing step.The whole process includes incoming inspection, vacuum smelting, hot forging, annealing softening, cold roll forming, CNC blanking, Argon arc welding, non-destructive testing of welds, acid passivation, hydrostatic test, Vacuum nitrogen-filled packaging.Key process points: The vacuum degree of vacuum smelting is controlled within 10Pa to ensure that the carbon element meets the standard;Single cold forming deformation should not exceed 25%, large deformation processing needs to add intermediate annealing;ERNi-1 welding wire, carbon content of welding wire is also controlled at 0.02%.Acid pickling can only use 20%-30% nitric acid, not with hydrofluoric acid;After welding, heat treatment can be selected as required. N4 materials do not require post-weld heat treatment.

N4 nickel material implementation related standards, GB/T 5235-2021 Designation and chemical composition of wrought nickel and nickel alloys, GB/T 2054-2013 Nickel and nickel alloy plates, ASTM B162 Specification for Nickel Alloy Plate, ASME BPVC Pressure Vessel Related Materials Code, Nuclear power projects will also refer to the RCC-M French Nuclear Island Equipment Specification, NB/T series pressure welding and nondestructive testing standards.In the procurement stage of nuclear power orders, it is recommended to refer to GB/T 5235, ASTM B162 and ASME BPVC Section III standards at the same time to reduce the procurement risk of N6 passing off as N4.

Market conditions for the second quarter of 2026, Domestic N4 sheet thickness 2-4mm annealed sheet price 220-260 yuan per kilogram, Import prices are about twice as high as domestic pricesThickness 4-10mm medium plate domestic 210-250 yuan per kilogram;10-30mm thick plate domestic 200-240 yuan per kg;Φ20-100mm N4 bar made in China 200-240 yuan per kg;4N5 electronic high purity N4 material domestic 800-1500 yuan per kilogram, import prices reached 2 to 2.5 times domestic.Compared with N6, the price of N4 material rises by 10%-15% due to low carbon smelting process;High purity 4N5 specification, the price is 4 to 5 times higher than that of ordinary industrial grade.Domestic Jinchuan, Baoji Nickel Industry can stably supply industrial grade N4, Imported materials are still selected for some scenarios of nuclear power first-class pressure-bearing components.

N4 material procurement exists inferior situation, recommend three-step identification method.First, the third-party carbon content detection, using infrared absorption or combustion method, genuine N4 carbon content ≤0.02%, N6 counterfeit products carbon content mostly in 0.05-0.10%;second, Determination of Nickel by XRF Spectroscopy, Genuine N4 Nickel Peak High, Nickel and cobalt content not less than 99.9%, Stainless steel impersonates products with obvious iron peak valueThird, density verification, N4 nickel density 8.89g/cm³, with the size plate compared to 316L stainless steel weight 12% higher.Procurement of N4 nickel plate, The contract needs to be clearly marked, carbon content index, Nickel cobalt purity, testing requirements, executive standard, Welding wire specification.

Five key points to avoid pits in processing links: strictly control carbon content and vacuum smelting;Hydrochloric acid is prohibited in pickling;Cold forming single channel deformation control to prevent plate cracking;ERNi-1 low carbon welding wire is selected for welding;Control the cutting speed, adapt the nickel material work hardening characteristic.Five Risk Points in Procurement Stage, Be wary of suppliers replacing N4 with N6, Non-vacuum smelting low-carbon substandard pseudo-N4, Stainless steel impersonates high purity nickel, Shrinkage of clad thickness, Omit third-party carbon testing.

FAQ

Q1: How to select N4 and N6?Working condition ≤315℃, whole annealing after welding, optional N6;Temperature greater than 315℃ or unable to post weld heat treatment, priority N4. Q2: N4 annealed mechanical properties?Tensile strength not less than 350 MPa, Yield ≥80MPa, Elongation ≥40%, Mechanical strength close to N6, The differences focus on carbon content and sensitivity. Q3: Is N4 resistant to hydrochloric acid?Dilute hydrochloric acid without oxidant can be used at room temperature, contains iron ions, Not suitable for hydrochloric acid environment of oxidizing agent such as nitrate, TA9 titanium can be selected.

Three major development directions of the industry: the restart of domestic nuclear power projects drives the demand for N4 nickel materials;Semiconductor industry promotes localization of high-purity nickel materials;Molten alkali evaporator large-scale, N4 composite plate demand continues to rise.

written in the end

N4 nickel plate is not a simple high-priced version of N6, it is a nickel material category suitable for ultra-high temperature and ultra-low carbon conditions.Compared to the N6 price rose slightly, But at 320℃ nuclear power equipment, high-purity semiconductor, the operation of that molten alkali reactor can be stable for a long time, N6 graphitization embrittlement will occur under such conditions.TA2 constitutes a set of corrosion resistant material selection system, N4 adapts to ultra-high temperature and low carbon pressure scenarios, N6 is suitable for concentrated alkali conditions within 315℃, TA9 Adapts Strong Reducing Acid, TA10 for chloride ion, Wet chlorine condition.If you are developing nuclear power equipment, high temperature reactor, Material selection of semiconductor target materials, This N4 nickel plate selection information can be used as a technical communication reference.

Shaanxi Qianyi Tuoda Technology Co., Ltd. is located in Baoji, China Titanium Valley, 12 years of titanium, nickel-based alloy, Hastelloy non-standard equipment and plate processing, N4 nickel plate can be provided with consultation on working condition selection, zero cut, Composite plate customization, Supporting welding technology one-stop service.

related readingtitanium pipeFull solution to selection

            Titanium PlateFull solution to selection

            titanium stirrerSelection Decision Guide

disclaimerMaterial parameters in this paper, price range, The project case is only used as a reference for technical selection, Does not constitute a technical commitment and commercial offer.The actual use effect of materials is affected by medium concentration, temperature fluctuation, processing and welding technology, and field operation and maintenance conditions.Shaanxi Qianyi Tuoda Technology Co., Ltd. reserves the right of final interpretation of this article.Technical consultation: 15909236031 / 0917-3557966.