--- title: "Inconel Machining | 625, 718 Nickel Superalloy Parts | OpenSpindle" description: "Get quotes for custom Inconel parts from independent machine shops. 625 and 718 nickel superalloy machined for high-heat and corrosive service. Upload a drawing." canonical: https://openspindle.com/materials/inconel --- # Custom Inconel parts from independent machine shops Inconel is a family of nickel-chromium superalloys that keep their strength and resist oxidation where steel and titanium give up: hot exhaust, turbines, and sour, corrosive service. Upload a drawing and hear back from shops set up for hard-to-machine superalloys. ## Inconel shops on OpenSpindle Real shops set up to machine nickel superalloys. See their equipment and get a competitive quote for your project. [Browse all Inconel shops](https://openspindle.com/manufacturers?material=Inconel%2C625%2C718) ## Inconel grades shops run most The grade sets whether the alloy is prized for corrosion resistance or for high-temperature strength. These are the two you will see quoted most. ### Inconel 625 Outstanding corrosion resistance and good strength up to high temperature, used as-welded without heat treatment. The choice for chemical, marine, and sour-service hardware. **Best for:** Sour service, chemical, marine, exhaust ### Inconel 718 A precipitation-hardening superalloy with very high strength that holds up to about 700 C. The workhorse for turbine and rocket hardware. Age-hardened after machining. **Best for:** Turbine, aerospace, and rocket structure ### Inconel 600 / 601 Nickel-chromium alloys for high-temperature oxidation resistance in furnaces and heat-treat fixtures, where scaling resistance matters more than strength. **Best for:** Furnace parts, heat-treat fixtures, thermal ### Hastelloy (related) A related family of nickel-molybdenum superalloys for the most aggressive chemical environments. Shops that run Inconel often run Hastelloy too. **Best for:** Severe chemical and acid service ## Material Properties Representative values for Inconel 718 in the aged condition. Exact numbers vary by grade and heat treatment. | Property | Value | | --- | --- | | Density | 8.19 g/cm³ (0.296 lb/in³) | | Tensile strength (718 aged) | ~205 ksi (1410 MPa) | | Yield strength (718 aged) | ~170 ksi (1170 MPa) | | Max service temp (718) | ~700 °C (1300 °F) with strength retained | | Max service temp (625, oxidation) | ~980 °C (1800 °F) | | Machinability | Difficult; work-hardens fast, needs rigid setups and low speeds | | Corrosion resistance | Excellent, including chloride and sour (H2S) service | | Weldability | Good, especially 625; 718 welded then aged | Inconel work-hardens as it is cut, so machining is slow and tooling-intensive. That, plus the raw stock cost, is why Inconel parts carry a premium. ## Stock Forms - **Round bar** -- Turned fittings, shafts, and valve parts. - **Sheet & plate** -- Cut and formed panels, flanges, and brackets. - **Tube & pipe** -- Seamless tube for exhaust, heat exchangers, and lines. ## Processes That Run This Material - [CNC Turning](https://openspindle.com/capabilities/cnc-turning.md) -- Turned fittings, valve bodies, and shafts from bar. - [CNC Machining](https://openspindle.com/capabilities/cnc-machining.md) -- Milled flanges, housings, and structural parts. - [CNC Machining · 5-Axis](https://openspindle.com/capabilities/5-axis-machining.md) -- Turbine and rocket geometry in a single setup. - [EDM](https://openspindle.com/capabilities/edm.md) -- Wire and sinker EDM for hard superalloy features and slots. - [Waterjet Cutting](https://openspindle.com/capabilities/waterjet-cutting.md) -- Cold cutting plate and sheet with no heat-affected edge. ## Finishes Inconel resists corrosion on its own, so finishing is usually about cleanliness and surface condition rather than protection. - **As-machined** -- Bare superalloy needs no coating for corrosion resistance and ships as-machined for most parts. - **Passivation** -- A cleaning treatment that removes free iron and restores the passive oxide layer for chemical and medical service. - **Bead blast** -- A uniform matte texture that removes tool marks; common before inspection or assembly. - **Electropolish** -- A smooth, ultra-clean surface for chemical, semiconductor, and sanitary applications. Call out any surface finish (Ra), passivation, or cleanliness requirement, since these drive cost on superalloy parts. ## Applications - Aerospace & defense - Energy / oil & gas - Turbomachinery - Chemical processing - Marine - Motorsport exhaust Inconel earns its premium where heat and corrosion rule out cheaper metals. ## How It Compares How Inconel compares to the other high-performance metals shops quote. ### [Stainless Steel](https://openspindle.com/materials/stainless-steel.md) - Inconel keeps strength and resists oxidation at temperatures where stainless softens and scales - Stainless is far cheaper and much easier to machine, and covers most corrosion needs - Inconel resists chloride and sour (H2S) cracking that attacks standard stainless **Verdict:** Choose Inconel for high heat and the most corrosive or sour service. Choose stainless for general corrosion resistance at a fraction of the cost. ### [Titanium](https://openspindle.com/materials/titanium.md) - Titanium is far lighter with excellent corrosion resistance at moderate temperature - Inconel holds strength at much higher temperatures where titanium weakens - Both are expensive and slow to machine; the choice is heat vs weight **Verdict:** Choose Inconel for high-temperature strength. Choose titanium when light weight and moderate-temperature corrosion resistance matter more. ## Frequently Asked Questions ### What is the difference between Inconel 625 and 718? 625 is prized for corrosion resistance and is used as-welded without heat treatment, making it the choice for chemical, marine, and sour-service hardware. 718 is a precipitation-hardening alloy with very high strength that holds up to about 700 C, used for turbine and rocket parts and age-hardened after machining. Pick 625 for corrosion, 718 for high-temperature strength. ### Why is Inconel expensive to machine? Inconel work-hardens rapidly as it is cut, so it demands rigid setups, sharp tooling, low speeds, and generous coolant, which makes cycle times long and tool wear high. Combined with costly nickel-alloy raw stock, that is why Inconel parts carry a premium over steel or aluminum. Budget extra lead time as well. ### Does Inconel need heat treatment? 625 is typically used in the as-machined or annealed condition with no hardening. 718 is precipitation (age) hardened after machining to reach full strength, which the shop coordinates. Note the required condition and any strength or hardness spec on your drawing. ### Is Inconel suitable for sour (H2S) service? Yes. Inconel 625 in particular resists chloride stress-corrosion cracking and sour, H2S-bearing environments that attack standard stainless, which is why it is used for oil-and-gas and downhole hardware. Confirm the specific NACE or service requirement so the shop selects the right grade and condition. ### Can shops weld Inconel? Yes. Inconel welds well, especially 625, which is often used as-welded. 718 is welded and then aged. Note welded joints and any post-weld requirements on your drawing so the shop plans filler and heat treatment. ### What files should I send for an Inconel part? STEP, IGES, X_T, or a dimensioned PDF. Include the grade (for example 625 or 718), the required condition or heat treatment, surface finish and any passivation or cleanliness spec, critical tolerances, and quantity. Expect longer lead times than steel or aluminum. ## Related Materials - [Stainless Steel](https://openspindle.com/materials/stainless-steel.md) - [Titanium](https://openspindle.com/materials/titanium.md) - [Alloy Steel](https://openspindle.com/materials/alloy-steel.md) - [Cobalt-Chrome](https://openspindle.com/materials/cobalt-chrome.md) - [Aluminum](https://openspindle.com/materials/aluminum.md) - [Copper](https://openspindle.com/materials/copper.md) ## Get Inconel part quotes Upload a drawing once and compare quotes from independent shops set up to machine Inconel 625 and 718.