R405 Hex Bar - UNS N04405 - Monel 405™ Equivalent
Monel R‑405™ is a nickel‑copper alloy developed as a free‑machining version of Monel 400. By increasing sulfur content, alloy R‑405 achieves significantly improved machinability while maintaining nearly the same corrosion resistance and physical properties as Monel 400.
Because of its controlled mechanical property range and excellent machining performance, Monel R‑405™ is especially recommended for screw machine stock and high‑volume precision components.
Typical applications include valve parts, fasteners, and mechanical components used in corrosive marine and seawater environments. Monel R‑405™ also offers exceptional resistance to de‑aerated hydrochloric and hydrofluoric acids, making it well‑suited for specific chemical processing applications. It should be noted that aeration of these acids can reduce corrosion resistance, particularly in fastener applications.
Contact us here for more information on available sizes of R-405™.
- Inventory & Specs
- Chemical Composition
- Physical Properties
- Mechanical Properties
- Additional Info
- FAQs
Characteristics of Monel R‑405™
Monel R‑405™ bar is a nickel‑copper alloy engineered to deliver the corrosion resistance of Monel 400 with significantly improved machinability. The addition of sulfur promotes effective chip breakage during machining, making this alloy especially suitable for high‑volume screw machine applications and precision‑turned components. Despite the enhanced machinability, Monel R‑405™ retains excellent resistance to seawater, brine, and many reducing chemical environments, along with high strength, toughness, and durability across a broad temperature range. It also offers good thermal and electrical conductivity and remains non‑magnetic in the annealed condition, making it reliable for demanding mechanical and marine service conditions.
Working With Monel R‑405™
Monel R‑405™ bar is best suited for machining‑focused applications where efficiency, dimensional accuracy, and tool life are critical. It machines substantially easier than standard Monel 400 and performs well on automatic screw machines and CNC equipment when sharp tooling and rigid setups are used. While limited cold working is possible, this alloy is primarily intended for machined parts rather than extensive forming operations. Welding is generally not recommended due to the sulfur content, which can increase the risk of hot cracking; mechanical fastening methods are typically preferred. In service, Monel R‑405™ performs exceptionally well in marine environments and in contact with de‑aerated hydrochloric and hydrofluoric acids, though corrosion resistance may diminish in strongly oxidizing or aerated conditions.
Other industry standards we comply with:
- QQ-N-281
Common Trade Names
- MONEL Alloy R-405™ (Special Metals Corporation Group)
- Alloy 405
- Alloy R-405
Industry Applications for R405
- Automatic Screw Machine Stock
- Fasteners
- Shafts
- Mechanical Hardware
- Valve Parts
Chemical Composition
| Element | Min | Max | |
|---|---|---|---|
| Ni | Nickel | (Plus Cobalt) 63.0 | - |
| C | Carbon | - | 0.3 |
| Mn | Manganese | - | 2.00 |
| Fe | Iron | - | 2.5 |
| S | Sulfur | 0.025 | 0.060 |
| Si | Silicon | - | 0.5 |
| Cu | Copper | 28.0 | 34.00 |
Physical Properties
| Property | Amount |
|---|---|
| Density, g/cm³ | 8.80 |
| Density, lb/in³ | 0.318 |
| Melting Range °F | 2370-2460 |
| Melting Range °C | 1300-1350 |
| Modulus of Elasticity | 10³ ksi |
| Tension | 26.0 |
| Compression | 26.0 |
| Torsion | 9.5 |
| Poisson's Ration | 0.32 |
| Curie Temperature °F | 70-120 |
| Curie Temperature °C | 21-49 |
Mechanical Properties
| Condition | Tensile Strength, ksi | Yield Strength (0.2% offset) ksi | Elongation % | Hardness Brinell | Hardness Rockwell B |
|---|---|---|---|---|---|
| Annealed | 70-85 | 25-40 | 50-35 | 110-140 | 60-76 |
| Hot Finished | 75-90 | 35-60 | 40-30 | 130-170 | 72-86 |
| Cold Drawn, As Drawn | 85-115 | 50-105 | - | 160-245 | 85-23C |
Additional Info
A Brief History of R405
Monel R‑405™—a free‑machining nickel‑copper alloy derived from Monel 400—was developed to meet the growing demand for corrosion‑resistant materials that could also be efficiently machined into high‑volume, precision components. Known for its enhanced sulfur content, Monel R‑405™ maintains the core corrosion resistance and durability of Monel 400 while offering improved machining performance. This combination made it an important material for industries requiring precision‑machined parts used in aggressive marine, chemical, and industrial environments.
How R405 Was Developed
Monel R‑405™ was engineered as a specialized modification of Monel 400 to address machining challenges associated with traditional nickel‑copper alloys. While Monel 400 provided excellent resistance to seawater, brine, and non‑oxidizing acids, its machining characteristics limited production efficiency for screw‑machined components. By increasing sulfur content in a controlled manner, metallurgists created Monel R‑405™—an alloy that promotes consistent chip breakage, improved tool life, and high dimensional accuracy while retaining nearly identical corrosion resistance and physical properties to Monel 400.
This balance of machinability and performance made Monel R‑405™ especially well-suited for automated machining operations.
Early Applications of R405
As industrial manufacturing shifted toward higher production volumes and tighter tolerances, Monel R‑405™ quickly gained acceptance in screw machine and precision machining applications. It became widely used for valve components, fasteners, fittings, and mechanical hardware exposed to seawater and corrosive chemical environments. Its resistance to de‑aerated hydrochloric and hydrofluoric acids further expanded its role in chemical processing and fluid handling systems where reliability and corrosion control were essential.
How R405 Is Used Today
Today, Monel R‑405™ bar remains a preferred material for machined components requiring corrosion resistance and manufacturing efficiency. Its controlled mechanical properties and improved machinability make it ideal for high‑volume precision parts across multiple industries, including:
- Marine & offshore: valve parts, shafts, fasteners, and seawater‑exposed hardware
- Chemical processing: valve stems, fittings, and fasteners used in reducing acid environments
- Oil & gas: flow control components and corrosion‑resistant fasteners
- Industrial valves & flow control: screw‑machined trim components and precision parts
- Fastener manufacturing: bolts, nuts, studs, and specialty hardware
Monel R‑405™ performs reliably in marine atmospheres and non‑oxidizing chemical environments where stainless steels and other alloys may suffer from accelerated corrosion. Its enhanced machinability continues to make it a cost‑effective solution for complex, high‑volume machined components.
Your Trusted Supplier for R405
United Performance Metals is a global specialty metals solutions provider offering Monel R‑405™ bar to support precision machining, marine, chemical, and industrial applications. With advanced FIRSTCUT+® processing services and proven expertise in high‑performance nickel alloys, UPM delivers Monel R‑405™ products cut to exact specifications and backed by dependable supply chain solutions.
Contact our team today to learn how Monel R‑405™ bar can enhance your next precision machining or corrosive‑service application.