Hastelloy CNC Machining
Superior corrosion resistance. Chemical resistant. Heat resistant. Maintains ductility.
Hastelloy Machining Overview
Hastelloy is a family of nickel-based super alloys renowned for their exceptional resistance to chemical corrosion. Where other materials would rapidly degrade in contact with aggressive acids, chlorides and oxidising environments, Hastelloy maintains its structural integrity and mechanical properties. This makes it the material of choice for the most demanding chemical processing, pharmaceutical and pollution control applications.
Like other nickel-based super alloys, Hastelloy presents significant machining challenges. Its tendency to work harden, combined with high strength and poor thermal conductivity, means that specialist knowledge and equipment are essential for producing quality components. Many UK machine shops lack the experience to work with Hastelloy reliably.
At Clarent Precision, we have proven experience machining Hastelloy C276 and other grades. Our portfolio includes components such as chemical processing stirrers in C276 Hastelloy, demonstrating our practical capability with this demanding material. We also machine C22, B2 and X grades as required.
Key Properties of Hastelloy
Superior Corrosion Resistance
Outstanding resistance to pitting, crevice corrosion and stress corrosion cracking in the most aggressive chemical environments.
Chemical Resistance
Resists attack from hydrochloric acid, sulphuric acid, phosphoric acid, acetic acid and many other corrosive chemicals.
Heat Resistant
Maintains strength and corrosion resistance at elevated temperatures up to 675°C for C276 and higher for other grades.
Maintains Ductility
Retains excellent ductility and toughness even after prolonged exposure to high temperatures and corrosive media.
Oxidation Resistant
Excellent resistance to oxidising and reducing environments, giving versatility across a wide range of chemical processes.
Weldable
Can be welded without post-weld heat treatment in most cases, allowing complex fabricated and machined assemblies.
The Hastelloy Machining Challenge
Hastelloy shares many of the machining challenges common to nickel-based super alloys. Understanding and managing these is essential for producing quality components.
- Work hardening: Hastelloy work hardens rapidly during machining. Consistent tool engagement and avoiding rubbing or dwelling is critical to prevent the surface from becoming unmachinable.
- Heat concentration: Poor thermal conductivity means cutting heat builds up at the tool tip, accelerating wear and potentially affecting surface integrity.
- Tool wear: The combination of hardness, heat and abrasive carbide particles in the alloy leads to rapid tool degradation. Correct tool selection and cutting parameters are essential.
- Surface finish: Achieving a good surface finish on Hastelloy requires sharp tooling, optimised speeds and feeds, and effective coolant delivery.
Our approach to Hastelloy machining involves specialist carbide and coated tooling, optimised cutting strategies, high-pressure coolant and the practical experience that comes from regularly working with nickel-based super alloys.
Our Hastelloy Machining Capabilities
- CNC Milling: 3 and 4 axis machining with high-pressure coolant. Sizes up to 762mm x 406mm x 508mm.
- CNC Turning: Live tooling lathes for complete mill-turn operations. Capacity up to Ø279mm x 413mm.
- Batch Sizes: From single prototypes to production batches. Milling runs up to 1,000+, turning up to 10,000.
- Tolerances: Routinely achieving +/- 0.01mm on critical dimensions, verified by CMM inspection.
- Grades: C276 (confirmed portfolio experience), C22, B2, X and others on request.
Applications and Industries
Hastelloy components are relied upon wherever aggressive chemicals and high temperatures combine.
- Chemical processing reactor vessels, agitators and stirrers
- Pollution control scrubbers and stack liners
- Waste treatment equipment
- Pharmaceutical processing equipment
- Petrochemical heat exchangers and piping components
- Flue gas desulphurisation systems
Post-Production Treatments
Hastelloy components may require specific treatments depending on the application and operating environment.
- Heat treatment: Solution annealing to optimise corrosion resistance and mechanical properties.
- Passivation: Chemical treatment to enhance the protective surface layer.
- Surface grinding: For precision sealing faces and critical tolerance requirements.
Hastelloy Component Examples
Examples of Hastelloy components produced at our Leighton Buzzard facility.
Hastelloy C276 chemical processing stirrer
Precision machined engineering component
Quality Assurance
Hastelloy components are typically used in safety-critical and process-critical applications where quality documentation is essential. Our ISO 9001 certified quality system provides full material traceability, Certificates of Conformity and detailed dimensional inspection reports. Every component is inspected in our temperature-controlled inspection department using CMM and precision hand tools.
Our quality systems →Frequently Asked Questions
What is Hastelloy C276?
Hastelloy C276 is a nickel-molybdenum-chromium super alloy with outstanding resistance to a wide range of chemical environments. It resists pitting, crevice corrosion and stress corrosion cracking in aggressive media including hydrochloric acid, sulphuric acid and chloride-containing solutions. It is the most versatile of the Hastelloy family and is widely used in chemical processing, pollution control and pharmaceutical applications.
What is the difference between Hastelloy and Inconel?
Both are nickel-based super alloys, but they are optimised for different conditions. Hastelloy is primarily designed for maximum corrosion resistance in aggressive chemical environments, while Inconel is optimised for maintaining strength at extreme high temperatures. In simple terms, choose Hastelloy when the primary concern is chemical attack, and Inconel when the primary concern is high-temperature mechanical performance.
What applications use Hastelloy?
Hastelloy is used extensively in chemical processing (reactor vessels, agitators, heat exchangers), pollution control (scrubbers, stack liners), pharmaceutical processing, waste treatment, petrochemical operations and flue gas desulphurisation. Any application involving exposure to aggressive acids, chlorides or mixed corrosive environments is a strong candidate for Hastelloy.
How much does Hastelloy CNC machining cost?
Hastelloy is one of the more expensive materials to machine due to high raw material costs, slow cutting speeds and increased tool consumption. The exact cost depends on component complexity, tolerances, batch size and the specific grade required. Send us your drawings for an accurate, competitive quotation. Our experience with Hastelloy allows us to optimise cutting strategies and minimise waste, keeping costs as low as possible.
Need Hastelloy Components Machined?
Proven C276 experience and deep super alloy expertise. Send us your drawings for a competitive quote.