1. Įvadas
Nikelis (chemical symbol Ni, atominis skaičius 28) yra plastiškas, silvery-white transition metal belonging to Group 10 periodinės lentelės.
Authoritative thermodynamic data from NIST and the Royal Society of Chemistry confirms that pure nickel has a standard melting point of 1455 ° C. (2651 ° F., 1728 K).
The elemental metal has a single melting point in practical terms, but nickel-base alloys usually melt over a range because alloying changes the solidus and liquidus temperatures.
Nickel’s melting behavior is one reason it is so widely used in corrosion-resistant and heat-resistant products.
Commercial nickel and nickel-base alloys are found in chemical processing equipment, Šilumokaičiai, furnace hardware, jūrų tarnyba, and high-temperature structural parts, where thermal stability and controlled solidification matter just as much as strength.
2. The Melting Point of Pure Nickel
For the elemental metal, nickel is generally treated as a single-melting-point material rather than a broad-range alloy.
Published values from different technical sources are extremely close, which is what engineers want from a reference metal: a stable number that can be used confidently in process design.
Representative values for pure nickel
| Medžiaga | Melting behavior | Inžinerinė prasmė |
| Grynas nikelis | 1453–1455°C / 2647–2651°F / 1726–1728 K | Elemental nickel is essentially a sharp-melting metal in practical use. |
The small spread between 1453°C and 1455°C is normal for published melting data.
It reflects differences in purity, measurement method, and rounding conventions rather than any meaningful change in the metal itself.
Inžineriniams tikslams, pure nickel should be treated as a metal with a melting point of about 1455° C..
3. Nickel Alloys and Melting Ranges
Nickel-base alloys do not behave like pure nickel.
Once other elements are added, the alloy usually develops a solidus ir skystis, so the metal begins to melt at one temperature and finishes melting at a higher one.
That is why alloy datasheets report a lydymosi diapazonas instead of a single point.
| Nickel grade / lydinys | melting range °C | melting range °F | melting range K |
| Nikelis 200 / Nikelis 201 | 1435–1445°C | 2610–2630°F | 1708.15–1718.15 K |
| Monel Alloy 400 | 1300–1350 ° C. | 2370–2460°F | 1573.15–1623.15 K |
| INCONEL Alloy 600 | 1354–1413°C | 2470–2580°F | 1627.15–1686.15 K |
| VDM Alloy 601 | 1330–1370°C | 2426–2498°F | 1603.15–1643.15 K |
| HAYNES / INCONEL 617 | 1330–1375°C | 2430–2510°F | 1603.15–1648.15 K |
| INCONEL Alloy 625 | 1290–1350 ° C. | 2350–2460°F | 1563.15–1623.15 K |
| INCONEL Alloy 718 | 1260–1336°C | 2300–2437°F | 1533.15–1609.15 K |
| HASTELLOY C-276 | 1323–1371°C | 2415–2500°F | 1596.15–1644.15 K |
| VDM Alloy 690 | 1390–1410°C | 2534–2570°F | 1663.15–1683.15 K |
4. Factors That Influence Nickel’s Melting Behavior
Grynumas
Purity is the first and most important factor.
Pure nickel shows a single, sharply defined melting point, while commercially pure grades such as Nickel 200/201 show a narrow melting range because even small compositional differences matter.
The closer the material is to elemental nickel, the closer it behaves to a one-point transition.
Legiravimo priedai
Alloying is the main reason nickel materials develop melting ranges.
Additions of copper, Chromas, lygintuvas, kobaltas, molibdenas, and other elements alter phase stability and shift the solidus and liquidus temperatures.
That is why Monel 400, Inconel 600, and ATI 617 each have a different melting interval even though all are nickel-based materials.
Product form and specification
Commercial nickel products may be supplied with slightly different published values depending on product form and supplier data sheet.
This does not mean the metal’s fundamental behavior has changed; it means the reported range reflects the exact grade, minor impurities, and product condition.
For process engineers, that is a reminder to use the supplier datasheet for the specific heat or lot rather than relying on a generic nickel value.
Thermal-process context
Nickel’s melting behavior must always be interpreted in context. A casting furnace, a brazing cycle, and a welding process do not use the same thermal target.
The melt range determines how much thermal headroom the operator has before the metal softens, begins to flow, or loses shape.
In nickel-base high-temperature alloys, that window is a core part of the design logic, not an afterthought.
5. Fizinis & Chemical Changes During Nickel Melting
Oksidacijos elgesys
Molten nickel is highly chemically active. Aukščiau 1000 ° C., nickel reacts rapidly with oxygen to generate nickel oxide (NiO).
Without inert gas protection, a dense dark oxide film covers the liquid surface, increasing smelting slag inclusion defects.
Industrial nickel melting must adopt argon shielding or vacuum smelting to isolate oxygen.
Solubility of Gas Elements
Molten nickel has strong hydrogen and nitrogen solubility. Gas solubility peaks near the melting point; excessive dissolved gas forms pinhole porosity after solidification.
Degassing treatment is mandatory for high-purity nickel castings.
Magnetic Transition
Nickel possesses ferromagnetism at room temperature. Its Curie temperature is 358 ° C.; above this critical temperature, nickel loses magnetism permanently until cooling down.
Magnetic disappearance during melting facilitates electromagnetic stirring in smelting furnaces.
6. How to Test the Melting Point of Nickel?
Differential scanning calorimetry and differential thermal analysis
For laboratory-scale determination, DSC ir DTA are the standard thermal-analysis tools for determining melting and crystallization temperatures of pure materials.
ASTM E794 states that this test method describes the determination of melting and crystallization temperatures by differential scanning calorimetry and differential thermal analysis, and that the method is useful for quality control, specification acceptance, and research.
Praktiškai, calibration is performed using known reference standards, and pure metals are commonly used as the calibration materials.
The melting temperature is typically taken from the extrapolated onset of the transition, while the sample is fully melted at the peak.
That makes DSC especially useful for nickel when a precise lab value is needed.
Optical pyrometry
For very hot industrial conditions, optinė pirometrija is a practical non-contact method because it measures thermal radiation from the hot object rather than requiring physical contact.
That makes it valuable for furnace observations, lydalo tvarkymas, and other high-temperature process checks where contact sensors may be impractical.
Practical comparison of methods
| Metodas | Geriausias naudojimas | Stiprybė | Apribojimas |
| DSC / DTA | Lab determination of melting and crystallization temperatures | Good for controlled measurement and calibration-based analysis | Requires small samples and controlled test conditions. |
| Optical pyrometry | Furnace and process temperature measurement | Non-contact and suitable for very hot surfaces | Measures radiative temperature in the viewing path, so setup and emissivity matter. |
7. Industrial Applications of Nickel Melting Range Control
PrecisionCasting
Į precizinis liejimas, the melting range determines how much thermal headroom the furnace must provide and how carefully the melt must be managed before pouring.
Pure nickel and nickel-base alloys are used in furnace components, chemical processing vessels, exchangers, high-temperature aerospace parts, branduoliniai reaktoriai, and turbines, which means the casting route has to handle both high temperature and aggressive service requirements.
For alloy castings, the important point is not the single melting point but the solidus-liquidus window.
A nickel-base alloy may start to freeze while part of the metal is still liquid, so foundry practice must account for feeding, susitraukimas, and solidification control across the full range.
That is an engineering inference from the published melt intervals of nickel-base alloys.
Suvirinimas
Nickel-base materials are widely welded because they can be joined by conventional welding processes and retain useful performance in demanding environments.
INCONEL Alloy 600 is described as readily joined by conventional welding processes, and the manufacturer lists specific welding materials for shielded metal-arc, gas tungsten-arc, and gas metal-arc joining.
MONEL Alloy 400 is also described as readily joined by conventional processes.
Suvirinimui, melting-range control matters because the base metal must not be overheated beyond the intended fusion zone.
Nickel alloys are often selected precisely because their melting intervals, stiprybė, and thermal response can support controlled joining in service-critical applications.
This is especially important when the welded part must remain dimensionally stable and corrosion resistant after fabrication.
Terminis apdorojimas
Heat treatment is another area where melting range control matters, because the operator must stay safely below any incipient-melting condition while still reaching the required thermal cycle.
ATI 617, pavyzdžiui, is normally solution annealed at 1175° C. (2150° F.), which sits below its published melting range of 1330–1380 ° C..
That gap is the usable thermal window that makes heat treatment possible without collapsing the microstructure.
The same logic applies more broadly to nickel-base alloys: heat treatment must be selected with the alloy’s solidus and liquidus in mind so the part gains the intended metallurgical state without partially melting.
In practical manufacturing, this is why nickel alloys are usually processed with much tighter temperature discipline than lower-melting metals.
8. Išvada
The melting point of pure nickel is about 1455° C. (1728 K / 2651° F.), with authoritative references clustering very close to that value.
The slight spread in published numbers is normal and reflects measurement history and rounding, not a meaningful engineering disagreement.
More importantly, nickel’s real industrial value lies in the way that melting behavior changes when nickel is alloyed.
Commercially pure nickel grades melt over a narrow range, while nickel-base alloys such as Monel 400, Inconel 600, and ATI 617 are engineered around their own solidus-liquidus intervals.
That is why nickel is not just a metal with a high melting point; it is a high-temperature platform for designing corrosion-resistant and heat-resistant materials.
DUK
What is the melting point of nickel in Celsius and Fahrenheit?
Pure nickel melts at about 1455° C., kuri yra apie 2651° F.. ASM gives a closely related value of 1453° C..
Why do nickel alloys have melting ranges instead of one exact point?
Because alloying changes phase equilibrium, so the material begins to melt at a solidus temperature and finishes melting at a higher skystis temperatūra.
Is pure nickel easier to process than nickel alloys?
Nebūtinai. Pure nickel has a sharp melting point, but nickel-base alloys are often selected because they offer better corrosion resistance, strength retention, or heat resistance for the intended service.
Why is nickel so important in high-temperature engineering?
Because it combines a high melting point with useful ductility and the ability to form heat-resistant alloy families used in furnace hardware, exchangers, aerokosminės dalys, and turbine-related systems.
