ZYTC Inconel® 751 (UNS N07751) Nickel-Chromium Alloy 

When heavy-duty diesel engine exhaust valves demand exceptional corrosion resistance at 913°C (1675°F) combined with high-temperature strength, material selection is critical. As an ISO 9001 and AS9120 certified supplier, ZYTC Alloy presents this technical guide for Inconel 751.

I. Product Information

• Material Name: Inconel® 751 Nickel-Chromium Alloy (UNS N07751)

• Definition: A modified version of Inconel X-750, specifically enhanced for exhaust valve applications. Retains all excellent physical, mechanical, and corrosion-resistant properties of X-750 while being optimized for aggressive combustion environments.

• Core Value: Exceptional resistance to lead oxide, sulfur, bromine, and chlorine at 913°C (1675°F) —proven by severe lead oxide screening tests showing remarkably low corrosion rates (avg. 4.31 g/dm²/h).

• Key Advantages:

  • Outstanding hot corrosion resistance (lead oxide, sulfur, halogens)

  • High-temperature strength to 913°C

  • Excellent creep resistance under thermal cycling

  • Readily weldable and machinable

• Certification: ISO 9001 & AS9120

• Product Forms: Pipes & Tubes | Sheets & Plates | Bars & Rods | Strips & Wires | Forgings

Chemical Composition (wt%):

C 0.10% max, Mn 1.0% max, Si 0.50% max, Cu 0.50% max, S 0.010% max.

II. Service Conditions & Selection Boundaries

Suitable Conditions (Why choose it?)

1. Heavy-Duty Diesel Exhaust Valves: Continuous exposure to combustion products at 913°C (1675°F) .

2. Lead Oxide Environments: Exceptional resistance to lead-based fuel additives.

3. Sulfur/Bromine/Chlorine Attack: Outstanding performance against halogen and sulfur corrosion.

4. Thermal Cycling Applications: Maintains integrity under repeated heating/cooling cycles.

Typical Applications:

• Heavy-Duty Diesel Engines: Exhaust valves for trucks, ships, locomotives, power generation

• High-Performance Engines: Racing and performance automotive exhaust valves

• Industrial: High-temperature components exposed to corrosive combustion products

Material Selection Boundaries (When to consider alternatives?)

• Need higher strength? → Consider Inconel 718 or X-750 (if corrosion less critical)

• Need maximum oxidation >1000°C? → Consider Inconel 601 or 602 CA

• Need aqueous corrosion resistance? → Consider Inconel 625

• Cost-sensitive applications? → Consider 21-2N or 21-4N valve steels (lower performance)

III. Manufacturing Process & Material Comparison

Heat Treatment Parameters:

Fabrication Guidelines:

• Machining: Conventional techniques (similar to iron-based alloys). Use water-based coolants for high-speed operations (turning, milling, grinding).

• Welding: Readily weldable using SMAW, GTAW/TIG, GMAW/MIG, submerged-arc.

• Cold Working: Effective using standard tooling.

Mechanical Properties (Precipitation Hardened, RT):

Material Comparison Guide:

Request a Quote Today:

For heavy-duty diesel exhaust valves and high-temperature components requiring exceptional corrosion resistance at 913°C, contact ZYTC Alloy for certified Alloy 751.

Contact us for free samples, technical data sheets, and competitive quotes.

Contact Us:

Email:daisy@zytcsteel.com

WhatsApp/WeChat: +86 17335753350