Stellite1 UNS R30001 Alloy Properties and Applications

# Stellite1 UNS R30001 Alloy Properties and Applications

## Introduction to Stellite1 UNS R30001

Stellite1, also known by its UNS designation R30001, is a cobalt-based alloy renowned for its exceptional wear resistance, high-temperature strength, and corrosion resistance. This alloy belongs to the family of Stellite alloys, which have been widely used in demanding industrial applications since their development in the early 20th century.

## Chemical Composition

The chemical composition of Stellite1 UNS R30001 plays a crucial role in its performance characteristics:

– Cobalt (Co): Primary base element (approximately 50-60%)
– Chromium (Cr): 25-32% for corrosion and oxidation resistance
– Tungsten (W): 3-6% for solid solution strengthening
– Carbon (C): 1.4-2.2% for carbide formation
– Small amounts of other elements like iron, silicon, and manganese

## Physical Properties

Stellite1 exhibits several notable physical properties:

– Density: Approximately 8.8 g/cm³
– Melting Point: Around 1290-1350°C (2350-2460°F)
– Thermal Conductivity: Moderate, about 14.6 W/m·K at 20°C
– Electrical Resistivity: Approximately 92 μΩ·cm
– Magnetic Properties: Generally non-magnetic in the annealed condition

## Mechanical Properties

The mechanical properties of Stellite1 make it suitable for demanding applications:

– Hardness: Typically 35-45 HRC in the annealed condition, can be increased through work hardening
– Tensile Strength: Approximately 800-1000 MPa (116-145 ksi)
– Yield Strength: Around 500-700 MPa (73-102 ksi)
– Elongation: 3-8% in 50 mm
– Impact Strength: Good resistance to impact and shock loading

## Corrosion Resistance

Stellite1 offers excellent corrosion resistance in various environments:

– Outstanding resistance to oxidizing acids and saltwater
– Good performance in alkaline solutions
– Resistance to pitting and crevice corrosion
– Maintains properties in high-temperature oxidizing atmospheres

## Wear Resistance

One of the most notable features of Stellite1 is its exceptional wear resistance:

– Excellent resistance to adhesive wear (galling)
– Good performance against abrasive wear
– Maintains hardness at elevated temperatures
– Low coefficient of friction in many applications

## Heat Treatment

Stellite1 typically does not require heat treatment for hardening as it achieves its properties through solid solution strengthening and carbide formation during solidification. However, stress relieving at 650-750°C (1200-1380°F) may be performed for certain applications.

## Fabrication and Machining

Working with Stellite1 presents some challenges:

– Difficult to machine due to its hardness and work-hardening characteristics

– Typically requires carbide or ceramic cutting tools
– Best fabricated using powder metallurgy or casting techniques
– Can be welded using matching filler metals and proper techniques

## Applications of Stellite1 UNS R30001

Stellite1 finds use in numerous industrial applications where wear resistance and corrosion resistance are critical:

### Industrial Applications

– Valve components (seats, stems, and trim)
– Pump parts for corrosive and abrasive services
– Bearing surfaces in harsh environments
– Wear plates and bushings

### Oil and Gas Industry

– Downhole tools and equipment
– Valve components for sour service
– Wear parts in drilling equipment

### Aerospace Applications

– High-temperature bearings and bushings
– Turbine components
– Wear-resistant coatings

### Other Applications

– Food processing equipment
– Chemical processing components
– Medical implants (in some specialized cases)

## Advantages of Stellite1

The key advantages of Stellite1 UNS R30001 include:

– Exceptional wear resistance in both corrosive and