PM Surface Treatments
Comprehensive surface finishing for powder metallurgy parts. Steam treatment for corrosion resistance, vacuum oil impregnation for self-lubrication, heat treatment for hardness, and protective coatings for harsh environments.
Quick Answer
Which surface treatment is right for a sintered part?
The best PM surface treatment depends on the failure mode you are trying to prevent. Steam treatment is commonly used for corrosion resistance and sealing porosity, oil impregnation supports self-lubricating bearing applications, and heat treatment or coatings are selected when wear or environmental exposure becomes the main concern.
Key Points
- Choose steam treatment when corrosion resistance and airtightness matter more than decorative finish.
- Choose oil impregnation for self-lubricating components that must run with minimal maintenance.
- Choose heat treatment or protective coatings for parts that face high wear, salt spray, or aggressive service environments.
Steam Treatment
Fe3O4 protective layer
Oil Impregnation
Self-lubricating properties
Heat Treatment
Hardening and tempering
Coatings
Corrosion protection
Steam Treatment
Steam Blackening / Oxidation
Heat treatment in a steam atmosphere to form a protective Fe3O4 magnetite layer on the surface and throughout the interconnected porosity.
Process Parameters
Typical Applications
Performance Benefits
Salt spray test per ASTM B117
HV increase due to oxide layer
Seals interconnected porosity
Decorative finish
Oil Impregnation
Vacuum Oil Impregnation
Vacuum-assisted impregnation of sintered parts with lubricating oil, providing self-lubricating performance for bearing applications.
Process Parameters
Typical Applications
Performance Benefits
Weight percentage in pores
Depending on oil type
Oil wicks to the surface during use
Maintenance-free operation
Heat Treatment
Quenching, Tempering & Case Hardening
Various heat treatment processes increase hardness, strength, and wear resistance through controlled metallurgical transformation.
Process Parameters
Typical Applications
Performance Benefits
Depending on process
For carburized parts
Carburized surface
Controlled atmosphere furnaces
Treatment Types
Protective Coatings
Dacromet, Electroplating & Phosphating
Surface coatings provide stronger corrosion protection, improved appearance, and application-specific functional performance.
Process Parameters
Typical Applications
Performance Benefits
Dacromet salt spray performance
Dacromet coating
RoHS compliant options
Metallic finish
Treatment Types
Treatment Selection Guide
| Requirement | Recommended Treatment | Expected Result |
|---|---|---|
| Corrosion resistance (outdoor or marine) | Steam Treatment + Dacromet | 1000+ hours salt spray |
| Self-lubricating bearings | Vacuum Oil Impregnation | 10,000+ hours service life |
| High wear resistance | Carburizing / Carbonitriding | HRC 60+ surface hardness |
| General-purpose hardness | Quench & Temper | HRC 35-50 throughout |
| Sealed porosity (airtight) | Steam Treatment | 10x airtightness improvement |