# 18Ni300 Alloy Powder Stainless Steel Nickel Material Properties and Applications
## Introduction to 18Ni300 Alloy Powder
18Ni300 alloy powder is a high-performance material widely used in various industrial applications. This powder is part of the maraging steel family, known for its exceptional strength, toughness, and corrosion resistance. The “18Ni” designation refers to its nickel content, while “300” indicates its nominal yield strength in ksi (kilopounds per square inch).
## Chemical Composition
The chemical composition of 18Ni300 alloy powder plays a crucial role in its properties:
– Nickel (Ni): 17-19%
– Cobalt (Co): 8-9%
– Molybdenum (Mo): 4-5%
– Titanium (Ti): 0.5-0.8%
– Aluminum (Al): 0.05-0.15%
– Carbon (C): ≤0.03%
– Iron (Fe): Balance
This carefully balanced composition contributes to the material’s unique characteristics.
## Mechanical Properties
18Ni300 alloy powder offers outstanding mechanical properties:
– Tensile Strength: 1900-2100 MPa
– Yield Strength: 1700-1900 MPa
– Elongation: 8-12%
– Hardness: 50-54 HRC (after aging)
– Impact Toughness: Excellent
– Fatigue Resistance: Superior
## Physical Properties
The physical properties of 18Ni300 alloy powder include:
– Density: 8.0 g/cm³
– Melting Point: 1410-1450°C
– Thermal Conductivity: 20 W/m·K
– Electrical Resistivity: 80 μΩ·cm
– Coefficient of Thermal Expansion: 11.5 × 10⁻⁶/°C
## Advantages of 18Ni300 Alloy Powder
18Ni300 alloy powder offers several advantages:
– Exceptional strength-to-weight ratio
– Good weldability without preheating
– Excellent dimensional stability during heat treatment
– High resistance to stress corrosion cracking
– Maintains properties at elevated temperatures
– Good machinability in annealed condition
## Applications of 18Ni300 Alloy Powder
Due to its unique properties, 18Ni300 alloy powder finds applications in various industries:
### Aerospace Industry
– Critical aircraft components
– Rocket motor casings
– Landing gear components
– High-stress fasteners
### Tooling and Molding
– Injection molds
– Die-casting dies
– Extrusion tools
– Forging dies
### Defense Applications
– Armor components
– Weapon systems
– Missile components
– Submarine parts
### Medical Industry
– Surgical instruments
– Implantable devices
– Dental tools
### Additive Manufacturing
18Ni300 alloy powder is particularly valuable in additive manufacturing (3D printing) applications:
– Complex aerospace components
– Custom tooling inserts
– High-performance prototypes
– Lightweight structural parts
## Heat Treatment Process
The heat treatment of 18Ni300 alloy powder typically involves:
1. Solution Annealing: 820-850°C followed by air cooling
2. Aging: 480-500°C for 3-6 hours
3. Optional Double Aging: For enhanced properties
This treatment sequence develops the material’s full strength potential while maintaining good toughness.
## Comparison with Other Materials
Compared to conventional stainless steels and nickel alloys, 18Ni300 offers:
– Higher strength than 17-4PH stainless steel
– Better toughness than tool steels
– Superior corrosion resistance to carbon steels
– More cost-effective than some nickel superalloys
## Surface Treatment Options
Various surface treatments can enhance 18Ni300’s performance:
– Nitriding for increased surface hardness
– Chrome plating for wear resistance
– Passivation for improved corrosion resistance
– Shot peening for fatigue life enhancement
## Mach