Monel K-500 (UNS N05500): Round Bars, Seamless Tubes & Plates — Technical Data Sheet

Quick Answer: What Is Monel K-500?

Monel K-500 (UNS N05500 / W.Nr. 2.4375) is a premier age-hardenable nickel-copper alloy formulated for service environments demanding high mechanical strength and exceptional corrosion resistance. Its high performance stems from the age hardening through aluminum (2.30–3.15%) and titanium (0.35–0.85%), which form ordered γ′ precipitates within its stable nickel-copper matrix. This requires a solution anneal followed by aging (precipitation hardening) to develop peak strength. Operating efficiently from cryogenic temperatures up to approximately 400°C (750°F) for sustained load-bearing service, Monel K-500 is widely utilized in marine propeller shafts, pump shafts, oil-well tools, and non-sparking fasteners.

Product Overview

At the atomic level, its face-centered cubic (FCC) austenitic matrix providing excellent toughness and ductility. Its primary advantage is nearly double the yield strength of Monel 400 while retaining outstanding seawater corrosion resistance, which yields exceptional resistance to flowing seawater, brine, and sour-gas environments, with good resistance to stress-corrosion cracking.

Shanghai Hangbo Alloy Group Co., Ltd., established in 2012, stands as a top-tier global manufacturer and supplier of Monel K-500. Operating under a certified ISO 9001:2015 quality management system, we command an export network covering 50+ countries. Our portfolio contains high-precision centerless ground round bars, heavy industrial plates, and high-pressure seamless tubing engineered for critical industrial applications. By managing carbon distribution and grain refinement during melting and forging, we ensure our material provides robust structural performance under severe stress. Every order comes with 100% material traceability and certified documentation, ensuring compliance with strict global engineering standards.

Executive Standards

Shanghai Hangbo Alloy Group Co., Ltd. manufactures Monel K-500 in strict compliance with international technical specifications:

Note: Shanghai Hangbo executes 100% confirmation of chemical compliance using Optical Emission Spectroscopy (OES) for every melt lot.

Chemical Composition

The corrosion-resistant profile of Monel K-500 depends on its exact chemical balance. Chromium ensures high-temperature oxidation resistance, while molybdenum safeguards against localized pitting in chloride environments.

Mechanical Properties

Monel K-500 delivers excellent design allowable stresses. The data below outlines typical properties for annealed stock.

Room-Temperature Mechanical Properties

High-Temperature Performance: Strength Retention Analysis

Monel K-500 retains remarkable mechanical properties under thermal stress, establishing its credentials as a critical superalloy:

How Monel K-500 Is Produced

Round Bar & Forging

• 1. VIM + ESR Double Melting: ensures high purity and uniform chemistry.
• 2. Hot Forging: heavy reduction refines grain structure.
• 3. Solution Annealing: rapid quenching to retain supersaturated solid solution.
• 4. Aging (Precipitation Hardening): 16-hour age at approximately 605°C develops peak γ′ strength.

Seamless Tube & Pipe

• 1. Billet Piercing & Extrusion: forged rounds pierced into hollows.
• 2. Cold Drawing: precise wall-thickness control.
• 3. Solution + Age: full heat treatment for age-hardened properties.
• 4. Defect Testing: hydrostatic and Eddy Current testing.

Sheet, Plate & Strip

• 1. Hot Rolling: controlled reduction.
• 2. Cold Rolling: ±0.05 mm gauge control.
• 3. Solution + Age: age-hardening heat treatment.
• 4. Pickling: nitric-hydrofluoric bath for clean surface.

Industry Applications: Solving Engineering Challenges

Marine & Offshore

K-500 is the premier alloy for propeller shafts, pump shafts, and valve stems in seawater, offering high strength with outstanding corrosion resistance.

Oil & Gas

Used for oil-well tools, drill collars, and downhole hardware exposed to sour (H2S) environments.

Chemical Processing

Suitable for pump and valve components handling brines, caustics, and non-oxidizing acids.

Non-Sparking Tools

Its non-sparking characteristic makes it valuable for tools used in flammable atmospheres.

Quality Assurance: 7-Stage Zero-Defect Inspection Protocol

Shanghai Hangbo Alloy Group Co., Ltd. deploys an intensive inspection matrix to support a zero-defect mandate across all production lines:

• 1. Chemical verification: OES analysis on every melt batch alongside handheld PMI validation on finished products ensures composition parameters match executive limits.
• 2. Ultrasonic Testing (UT): Performed per ASTM A388 standards across all bars and plates to confirm the absence of inner voids, seams, or gas inclusions.
• 3. Eddy Current Testing (ET): Applied 100% to tubes following ASTM E309 protocols to check surface and sub-surface continuity.
• 4. Hydrostatic Pressure Verification: Tubes undergo hydrostatic tests up to 10,000 PSI to verify wall integrity under high-pressure parameters.
• 5. Mechanical Destructive Testing: Tensile, offset yield, elongation, and Brinell hardness examinations are executed per heat lot to verify strength criteria.
• 6. Dimensional Metrology Check: Digital calipers and computerized laser sensors measure geometry, guaranteeing all diameter, wall, and length tolerances match orders.
• 7. Visual and Microstructure Audit: Surface quality checks are paired with metallographic microscope tests to evaluate grain size (ASTM E112) and phase homogeneity.

All items leave our facilities accompanied by ISO 9001:2015 certification and EN 10204 3.1 Mill Test Certificates. Third-party inspection options through SGS, TUV, or Bureau Veritas (BV) are organized upon customer request.

Frequently asked questions