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→Inconel alloys: bellows |
There's no actual evidence that SX refers to monocrystaline catered alloys in this instance. SX means SpaceX here. Monocrystalline casting isn't necessary in this application. |
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[[File:Inconel 718.JPG|thumb|Inconel 718 round bar]]
'''Inconel''' is a [[nickel]]-[[chromium]]-based [[superalloy]] often utilized in extreme environments where components are subjected to high temperature, pressure or [[Mechanical load|mechanical loads]]. Inconel alloys are [[oxidation]]- and [[corrosion]]-resistant. When heated, Inconel forms a thick, stable, [[passivation (chemistry)|passivating]] oxide layer protecting the surface from further attack. Inconel retains strength over a wide temperature range, attractive for high-temperature applications where
Inconel alloys are typically used in high temperature applications. Common trade names for various Inconel alloys include:
*
*
*
== History ==
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==Specific data==
{| class="sortable wikitable" style="text-align:
|-
! Alloy
! [[Solidus (chemistry)|Solidus]] °C (°F)
! [[Liquidus]] °C (°F)
|-
|align="left"| Inconel 600<ref>{{cite web |title = NINC30 |department=ASM Material Data Sheet |website=asm.matweb.com |url=http://asm.matweb.com/search/SpecificMaterial.asp?bassnum=NINC30
| 1354 ({{convert|1354|C|F|disp=number}})
| 1413 ({{convert|1413|C|F|disp=number}})
|-
|align="left"| Inconel 617<ref>{{cite web |title = Inconel 617 Alloy |website = American Elements |url=https://www.americanelements.com/inconel-617-alloy
| 1332 ({{convert|1332|C|F|disp=number}})
| 1377 ({{convert|1377|C|F|disp=number}})
|-
|align="left"| Inconel 625<ref>{{cite web |title = Inconel 625 Alloy |website = American Elements |url=https://www.americanelements.com/inconel-625-alloy
| 1290 ({{convert|1290|C|F|disp=number}})
| 1350 ({{convert|1350|C|F|disp=number}})
|-
|align="left"| Inconel 690<ref>{{cite web |title = Inconel 690 Alloy |website = American Elements |url=https://www.americanelements.com/inconel-690-alloy
| 1343 ({{convert|1343|C|F|disp=number}})
| 1377 ({{convert|1377|C|F|disp=number}})
|-
|align="left"| Inconel 718<ref>{{cite web |title = Inconel 718 Alloy |website = American Elements |url=https://www.americanelements.com/inconel-718-alloy
| 1260 ({{convert|1260|C|F|disp=number}})
| 1336 ({{convert|1336|C|F|disp=number}})
|-
|align="left"| Inconel X-750<ref>{{cite web |title = NINC35 |department=ASM Material Data Sheet |website=asm.matweb.com |url=http://asm.matweb.com/search/SpecificMaterial.asp?bassnum=NINC35
| 1390 ({{convert|1390|C|F|disp=number}})
| 1430 ({{convert|1430|C|F|disp=number}})
|}
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|-
| 600<ref>[http://www.specialmetals.com/assets/smc/documents/alloys/inconel/inconel-alloy-600.pdf Inconel alloy 600] {{Webarchive|url=https://web.archive.org/web/20210127104028/https://www.specialmetals.com/assets/smc/documents/alloys/inconel/inconel-alloy-600.pdf |date=2021-01-27 }}, Special Metals Corporation</ref>
| ≥72.0{{efn|Includes [[cobalt]]}}
| 14.0–17.0
| 6.0–10.0
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== Strengthening mechanisms ==
The most prevalent hardening mechanisms for Inconel alloys are [[Precipitation hardening|precipitate strengthening]] and [[solid solution strengthening]]. In Inconel alloys, one of the two often dominates. For alloys like Inconel 718, precipitate strengthening is the main strengthening mechanism. The majority of strengthening comes from the presence of gamma double prime (γ″) precipitates.<ref name="Mignanelli-2017">{{Cite journal |last1=Mignanelli |first1=P. M. |last2=Jones |first2=N. G. |last3=Pickering |first3=E. J. |last4=Messé |first4=O. M. D. M. |last5=Rae |first5=C. M. F. |last6=Hardy |first6=M. C. |last7=Stone |first7=H. J. |date=2017-07-15 |title=Gamma-gamma prime-gamma double prime dual-superlattice superalloys |journal=Scripta Materialia |language=en |volume=136 |pages=136–140 |doi=10.1016/j.scriptamat.2017.04.029 |issn=1359-6462|doi-access=free }}</ref><ref name="Devaux-2008">{{Cite journal |last1=Devaux |first1=A. |last2=Nazé |first2=L. |last3=Molins |first3=R. |last4=Pineau |first4=A. |last5=Organista |first5=A. |last6=Guédou |first6=J. Y. |last7=Uginet |first7=J. F. |last8=Héritier |first8=P. |date=2008-07-15 |title=Gamma double prime precipitation kinetic in Alloy 718 |url=https://www.sciencedirect.com/science/article/pii/S0921509307016073 |journal=Materials Science and Engineering: A |language=en |volume=486 |issue=1 |pages=117–122 |doi=10.1016/j.msea.2007.08.046 |issn=0921-5093}}</ref><ref name="Hosseini-2019">{{Cite journal |last1=Hosseini |first1=E. |last2=Popovich |first2=V. A. |date=2019-12-01 |title=A review of mechanical properties of additively manufactured Inconel 718 |url=https://www.sciencedirect.com/science/article/pii/S221486041930226X |journal=Additive Manufacturing |language=en |volume=30 |pages=100877 |doi=10.1016/j.addma.2019.100877 |issn=2214-8604}}</ref><ref name="Shankar-2001">{{Cite journal |last1=Shankar |first1=Vani |last2=Bhanu Sankara Rao |first2=K |last3=Mannan |first3=S. L |date=2001-02-01 |title=Microstructure and mechanical properties of Inconel 625 superalloy |url=https://www.sciencedirect.com/science/article/pii/S0022311500007236 |journal=Journal of Nuclear Materials |language=en |volume=288 |issue=2 |pages=222–232 |doi=10.1016/S0022-3115(00)00723-6 |bibcode=2001JNuM..288..222S |issn=0022-3115}}</ref> Inconel alloys have a γ matrix phase with an [[Face Centered Cubic | FCC]] structure.<ref name="Hosseini-2019" /><ref name="Tucho-2017">{{Cite journal |last1=Tucho |first1=Wakshum M. |last2=Cuvillier |first2=Priscille |last3=Sjolyst-Kverneland |first3=Atle |last4=Hansen |first4=Vidar |date=2017-03-24 |title=Microstructure and hardness studies of Inconel 718 manufactured by selective laser melting before and after solution heat treatment |url=https://www.sciencedirect.com/science/article/pii/S092150931730223X |journal=Materials Science and Engineering: A |language=en |volume=689 |pages=220–232 |doi=10.1016/j.msea.2017.02.062 |issn=0921-5093}}</ref><ref name="Yu-2021">{{Cite journal |last1=Yu |first1=Xiaobin |last2=Lin |first2=Xin |last3=Tan |first3=Hua |last4=Hu |first4=Yunlong |last5=Zhang |first5=Shuya |last6=Liu |first6=Fencheng |last7=Yang |first7=Haiou |last8=Huang |first8=Weidong |date=2021-02-01 |title=Microstructure and fatigue crack growth behavior of Inconel 718 superalloy manufactured by laser directed energy deposition |url=https://www.sciencedirect.com/science/article/pii/S0142112320305375 |journal=International Journal of Fatigue |language=en |volume=143 |pages=106005 |doi=10.1016/j.ijfatigue.2020.106005 |issn=0142-1123}}</ref><ref name="Jambor-2017">{{Cite journal |last1=Jambor |first1=Michal |last2=Bokůvka |first2=Otakar |last3=Nový |first3=František |last4=Trško |first4=Libor |last5=Belan |first5=Juraj |date=2017-06-01 |title=Phase Transformations in Nickel base Superalloy Inconel 718 during Cyclic Loading at High Temperature |journal=Production Engineering Archives |language=en |volume=15 |issue=15 |pages=15–18 |doi=10.30657/pea.2017.15.04|doi-access=free }}</ref> γ″ precipitates are made of Ni and Nb, specifically with a Ni<sub>3</sub>Nb composition. These precipitates are fine, coherent, disk-shaped, intermetallic particles with a tetragonal structure.<ref name="Devaux-2008" /><ref name="Hosseini-2019" /><ref name="Shankar-2001" /><ref name="Tucho-2017" /><ref name="Bennett-2021">{{Cite journal |last1=Bennett |first1=Jennifer |last2=Glerum |first2=Jennifer |last3=Cao |first3=Jian |date=2021-01-01 |title=Relating additively manufactured part tensile properties to thermal metrics |url=https://www.sciencedirect.com/science/article/pii/S0007850621000779 |journal=CIRP Annals |language=en |volume=70 |issue=1 |pages=187–190 |doi=10.1016/j.cirp.2021.04.053 |issn=0007-8506}}</ref><ref name="Li-2020">{{Cite journal |last1=Li |first1=Zuo |last2=Chen |first2=Jing |last3=Sui |first3=Shang |last4=Zhong |first4=Chongliang |last5=Lu |first5=Xufei |last6=Lin |first6=Xin |date=2020-01-01 |title=The microstructure evolution and tensile properties of Inconel 718 fabricated by high-deposition-rate laser directed energy deposition |url=https://www.sciencedirect.com/science/article/pii/S2214860419308450 |journal=Additive Manufacturing |language=en |volume=31 |pages=100941 |doi=10.1016/j.addma.2019.100941 |issn=2214-8604}}</ref><ref name="Glerum-2021">{{Cite journal |last1=Glerum |first1=Jennifer |last2=Bennett |first2=Jennifer |last3=Ehmann |first3=Kornel |last4=Cao |first4=Jian |date=2021-05-01 |title=Mechanical properties of hybrid additively manufactured Inconel 718 parts created via thermal control after secondary treatment processes |url=https://www.sciencedirect.com/science/article/pii/S0924013621000078 |journal=Journal of Materials Processing Technology |language=en |volume=291 |pages=117047 |doi=10.1016/j.jmatprotec.2021.117047 |issn=0924-0136}}</ref><ref name="Deng-2018">{{Cite journal |last1=Deng |first1=Dunyong |last2=Peng |first2=Ru Lin |last3=Brodin |first3=Håkan |last4=Moverare |first4=Johan |date=2018-01-24 |title=Microstructure and mechanical properties of Inconel 718 produced by selective laser melting: Sample orientation dependence and effects of post heat treatments |url=https://www.sciencedirect.com/science/article/pii/S0921509317316416 |journal=Materials Science and Engineering: A |language=en |volume=713 |pages=294–306 |doi=10.1016/j.msea.2017.12.043 |issn=0921-5093}}</ref>
Secondary precipitate strengthening comes from gamma prime (γ') precipitates. The γ' phase can appear in multiple compositions such as Ni<sub>3</sub>(Al, Ti).<ref name="Devaux-2008" /><ref name="Hosseini-2019" /><ref name="Shankar-2001" /> The precipitate phase is coherent and has an FCC structure, like the γ matrix;<ref name="Deng-2018" /><ref name="Tucho-2017" /><ref name="Bennett-2021" /><ref name="Li-2020" /><ref name="Glerum-2021" /> The γ' phase is much less prevalent than γ″. The volume fraction of the γ″ and γ' phases are approximately 15% and 4% after precipitation, respectively.<ref name="Devaux-2008" /><ref name="Hosseini-2019" /> Because of the coherency between the γ matrix and the γ' and γ″ precipitates, strain fields exist that obstruct the motion of dislocations. The prevalence of carbides with MX(Nb, Ti)(C, N) compositions also helps to strengthen the material.<ref name="Hosseini-2019" /> For precipitate strengthening, elements like niobium, titanium, and tantalum play a crucial role.<ref name="Aeether">{{Cite web |author=Aeether Co Limited |title=What is Solid Solution? Why do Nickel Alloy / Superalloy need Solution Treatment? |url=https://www.aeether.com/AEETHER/media/media-29/media.html |access-date=2023-05-08 |website=aeether.com |language=en}}</ref>
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Another common phase in Inconel alloys is the Laves intermetallic phase. Its compositions are (Ni, Cr, Fe)<sub>x</sub>(Nb, Mo, Ti)<sub>y</sub> and Ni<sub>y</sub>Nb, it is brittle, and its presence can be detrimental to the mechanical behavior of Inconel alloys.<ref name="Tucho-2017" /><ref name="Deng-2018" /><ref name="Sohrabi-2018">{{Cite journal |last1=Sohrabi |first1=Mohammad Javad |last2=Mirzadeh |first2=Hamed |last3=Rafiei |first3=Mohsen |date=2018-08-01 |title=Solidification behavior and Laves phase dissolution during homogenization heat treatment of Inconel 718 superalloy |url=https://www.sciencedirect.com/science/article/pii/S0042207X18305700 |journal=Vacuum |language=en |volume=154 |pages=235–243 |doi=10.1016/j.vacuum.2018.05.019 |bibcode=2018Vacuu.154..235S |issn=0042-207X}}</ref> Sites with large amounts of Laves phase are prone to crack propagation because of their higher potential for stress concentration.<ref name="Li-2020" /> Additionally, due to its high Nb, Mo, and Ti content, the Laves phase can exhaust the matrix of these elements, ultimately making precipitate and solid-solution strengthening more difficult.<ref name="Glerum-2021" /><ref name="Sohrabi-2018" /><ref name="Yu-2021" />
For alloys like Inconel 625, solid-solution hardening is the main strengthening mechanism. Elements like Mo {{clarification needed | date= July 2024}} are important in this process. Nb and Ta can also contribute to solid solution strengthening to a lesser extent.<ref name="Aeether" /> In solid solution strengthening, Mo atoms are substituted into the γ matrix of Inconel alloys. Because Mo atoms have a significantly larger radius than those of Ni (209 pm and 163 pm, respectively), the substitution creates strain fields in the crystal lattice, which hinder the motion of dislocations, ultimately strengthening the material.
The combination of elemental composition and strengthening mechanisms is why Inconel alloys can maintain their favorable mechanical and physical properties, such as high strength and fatigue resistance, at elevated temperatures, specifically those up to 650°C.<ref name="Mignanelli-2017" />
==Machining==
Inconel is a difficult metal to shape and to machine using traditional [[cold forming]] techniques due to rapid [[work hardening]]. After the first machining pass, work hardening tends to plastically deform either the workpiece or the tool on subsequent passes. For this reason, age-hardened Inconels such as 718 are typically machined using an aggressive but slow cut with a hard tool, minimizing the number of passes required. Alternatively, the majority of the machining can be performed with the workpiece in a "solutionized" form,{{clarification needed|date=September 2022}} with only the final steps being performed after age hardening. However some claim{{
External [[screw thread|threads]] are machined using a [[lathe]] to "single-point" the threads or by rolling the threads in the solution treated condition (for hardenable alloys) using a [[screw machine (automatic lathe)|screw machine]]. Inconel 718 can also be roll-threaded after full aging by using [[induction heat]] to {{Convert|700|C|-1}} without increasing the grain size.{{Citation needed|date=January 2010}} Holes with internal threads are made by threadmilling. Internal threads can also be formed using a sinker [[electrical discharge machining]] (EDM).{{citation needed|date=August 2013}}
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==Uses==
[[File:Astra_Rocket_Engine_—_Delphin_3.0.jpg|thumb|Delphin 3.0 rocket engine, used on [[Astra Rocket]]. 3D-printed in Inconel]]
Inconel is often encountered in extreme environments. It is common in [[gas turbine]] blades, seals, and combustors, as well as [[turbocharger]] rotors and seals, electric submersible well pump motor shafts, high temperature fasteners, chemical processing and [[pressure vessel]]s, [[heat exchanger]] tubing, steam generators and core components in nuclear [[pressurized water reactors]],<ref>{{cite web|url=http://www.specialmetals.com/documents/Inconel%20alloy%20625.pdf|archive-url=https://wayback.archive-it.org/all/20090226220715/http://www.specialmetals.com/documents/Inconel%20alloy%20625.pdf|url-status=dead|archive-date=2009-02-26|title=''Inconel alloy 625'', Specials Metals, 2015}}</ref> [[natural gas processing]] with contaminants such as H<sub>2</sub>S and CO<sub>2</sub>, [[firearm]] [[suppressor|sound suppressor]] blast baffles, and [[Formula One racing|Formula One]], [[NASCAR]], [[National Hot Rod Association|NHRA]], and [[Audi Performance and Racing|APR, LLC]] exhaust systems.<ref>[http://www.specialmetals.com/power.php Power Generation] {{webarchive|url=https://archive.today/20120914045808/http://www.specialmetals.com/power.php |date=2012-09-14 }}, Special Metals Corporation.</ref><ref>[http://www.specialmetals.com/chemical.php Chemical Processing] {{webarchive|url=https://archive.today/20130202213225/http://www.specialmetals.com/chemical.php |date=2013-02-02 }}, Special Metals Corporation.</ref> It is also used in the turbo system of the 3rd generation [[Mazda RX7]], and the exhaust systems of high powered [[Wankel engine]]
===Aerospace===
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* [[North American Aviation]] constructed the skin of the [[North American X-15]] [[rocket-powered aircraft]] out of Inconel X/750 alloy.<ref>Robert S. Houston, Richard P. Hallion, and Ronald G. Boston, [http://www.hq.nasa.gov/office/pao/History/hyperrev-x15/ch-0.html Editor's introduction, "Transiting from Air to Space: The North American X-15"] {{Webarchive|url=https://web.archive.org/web/20070810061825/http://www.hq.nasa.gov/office/pao/History/hyperrev-x15/ch-0.html |date=2007-08-10 }}, ''The Hypersonic Revolution: Case Studies in the History of Hypersonic Technology'', Air Force History and Museums Program, 1998. NASA.gov.</ref>
* [[Rocketdyne]] used Inconel X-750 for the thrust chamber of the [[F-1 (rocket engine)|F-1 rocket engine]] used in the first stage of the [[Saturn V]] booster.<ref>Anthony Young, "The Saturn V Booster: Powering Apollo into History", Springer-Verlag, 2009.</ref>
* [[SpaceX]] uses
* In a first for [[3D-printer|3D printing]], the SpaceX [[SuperDraco]] [[rocket engine]] that provides [[launch escape system]] for the [[Dragon V2]] crew-carrying [[space capsule]] is fully printed. In particular, the engine combustion chamber is printed of Inconel using a process of [[direct metal laser sintering]], and operates at very high temperature and a [[chamber pressure]] of {{convert|1000|psi|MPa|disp=flip}}.<ref name=ludiInco/><ref name=aw20140530>{{cite news |last=Norris |first=Guy |title=SpaceX Unveils 'Step Change' Dragon 'V2' |url=http://aviationweek.com/space/spacex-unveils-step-change-dragon-v2 |access-date=2014-05-30 |newspaper=Aviation Week |date=2014-05-30 |archive-date=2014-05-31 |archive-url=https://web.archive.org/web/20140531110355/http://aviationweek.com/space/spacex-unveils-step-change-dragon-v2 |url-status=dead }}</ref><ref name=sdc20140529>{{cite news |last=Kramer|first=Miriam |title=SpaceX Unveils Dragon V2 Spaceship, a Manned Space Taxi for Astronauts — Meet Dragon V2: SpaceX's Manned Space Taxi for Astronaut Trips |url=http://www.space.com/26063-spacex-unveils-dragon-v2-manned-spaceship.html |access-date=2014-05-30 |newspaper=space.com |date=2014-05-30 }}</ref><ref name=nsf20140530>
{{cite news |last=Bergin|first=Chris |title=SpaceX lifts the lid on the Dragon V2 crew spacecraft |url=http://www.nasaspaceflight.com/2014/05/spacex-lifts-the-lid-dragon-v2-crew-spacecraft/ |access-date=2015-03-06 |newspaper=NASAspaceflight.com |date=2014-05-30 }}</ref><ref name=nsj20140530>{{cite news |last=Foust|first=Jeff |url=http://www.newspacejournal.com/2014/05/30/spacex-unveils-its-21st-century-spaceship/|title=SpaceX unveils its "21st century spaceship" |access-date=2015-03-06 |newspaper=NewSpace Journal |date=2014-05-30}}</ref><ref name=sx20140801>{{cite web |title=SpaceX Launches 3D-Printed Part to Space, Creates Printed Engine Chamber for Crewed Spaceflight |url=http://www.spacex.com/news/2014/07/31/spacex-launches-3d-printed-part-space-creates-printed-engine-chamber-crewed |publisher=SpaceX |access-date=2015-03-06 |quote=''Compared with a traditionally cast part, a printed [part] has superior strength, ductility, and fracture resistance, with a lower variability in materials properties. ... The chamber is regeneratively cooled and printed in Inconel, a high performance superalloy. Printing the chamber resulted in an order of magnitude reduction in lead-time compared with traditional machining – the path from the initial concept to the first hotfire was just over three months. During the hotfire test, ... the SuperDraco engine was fired in both a launch escape profile and a landing burn profile, successfully throttling between 20% and 100% thrust levels. To date the chamber has been fired more than 80 times, with more than 300 seconds of hot fire.'' |archive-date=2017-08-25 |archive-url=https://web.archive.org/web/20170825191053/http://www.spacex.com/news/2014/07/31/spacex-launches-3d-printed-part-space-creates-printed-engine-chamber-crewed |url-status=dead }}</ref><!-- this source also has an excellent-quality photo of the printed SuperDraco rocket engine combustion chamber, but I am unsure how Fair Use works and whether it might be possible to use the image on Wikipedia. -->
* SpaceX cast the [[Raptor (SpaceX)|Raptor]] rocket engine manifolds from SX300, later SX500, which are
===Automotive===
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==Inconel alloys==
[[Alloy]]s of
* Inconel 188: Readily fabricated for commercial gas turbine and aerospace applications.
* Inconel 230: Alloy 230 Plate & Sheet mainly used by the power, aerospace, chemical processing and industrial heating industries.
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* Inconel 601
* Inconel 617: Solid solution strengthened (nickel-chromium-cobalt-molybdenum), high-temperature strength, corrosion and oxidation resistant, high workability and weldability.<ref>{{cite web |date=March 2005 |title=Inconel alloy 617 |url=https://www.specialmetals.com/documents/technical-bulletins/inconel/inconel-alloy-617.pdf |access-date=14 July 2022}}</ref> Incorporated in [[ASME Boiler and Pressure Vessel Code]] for high temperature nuclear applications such as [[molten salt reactor]]s {{circa}} April, 2020.<ref>{{cite web|title=Commercial alloy qualified for new use, expanding nuclear operating temperature|publisher=U.S. Department of Energy [[Idaho National Laboratory]]|date=April 28, 2020|url=https://inl.gov/article/a-new-material-expands-nuclear-operating-temperature/}}</ref>
* [[Inconel 625]]: Acid resistant, good weldability.<ref>{{cite web |url=https://www.refractorymetal.org/inconel-625/ |title=Inconel 625 |website=Advanced Refractory Metal |access-date=Aug 11, 2024}}</ref> The LCF version is typically used in [[bellows]]. It is commonly used for applications in [[aeronautic]], aerospace, marine, chemical and petrochemical industries.<ref>{{cite journal |last1=Oliveira |first1=Mauro |last2=Couto |first2=Antonio |year=2019 |title=Mechanical Behavior of Inconel 625 at Elevated Temperatures |journal=Metals |volume=9 |issue=3 |page=301 |doi=10.3390/met9030301 |doi-access=free}}</ref> It is also used for reactor-core and control-rod components in pressurized water reactors and as heat exchanger tubes in ammonia cracker plants for heavy water production.<ref>{{cite journal |last1=Shankar |first1=Vani |last2=Rao |first2=K.B. |year=2001 |title=Microstructure and mechanical properties of Inconel 625 superalloy |journal=Journal of Nuclear Materials |volume=288 |issue=2-3 |pages=222-232 |doi=10.1016/S0022-3115(00)00723-6}}</ref>
* Inconel 690: Low cobalt content for nuclear applications, and low resistivity<ref>[http://www.ndt-ed.org/GeneralResources/MaterialProperties/ET/Conductivity_Iron.pdf Inconel alloy 690] {{Webarchive|url=https://web.archive.org/web/20131112040149/http://www.ndt-ed.org/GeneralResources/MaterialProperties/ET/Conductivity_Iron.pdf |date=2013-11-12 }}, NDT Resource Center</ref>
* Inconel 706
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* Inconel 738
* Inconel X-750: Commonly used for gas turbine components, including blades, seals and rotors.
* Inconel 751: Increased
* Inconel 792: Increased
* Inconel 907
* Inconel 909
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==References==
{{reflist|
[[Category:Nickel–chromium alloys]]
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