Vacuum Age Hardening
(Precipitation Hardening)
Vacuum Age Hardening (Precipitation Hardening)
Age Hardening (Precipitation Hardening): Overview and Process
Age hardening, also known as precipitation hardening, is a heat treatment process used to enhance the strength of metals and alloys. This process strengthens the metal by forming solid precipitates within the metal’s structure, thus the name “precipitation hardening.” The treatment involves “aging” the metal by either heating it or storing it at lower temperatures, encouraging the formation of these precipitates.
Malleable metals and alloys, such as those of nickel, magnesium, and titanium, are well-suited for age hardening. Through this process, tensile and yield strength are significantly increased. The precipitates act as obstacles to dislocation movements or defects within the metal’s crystal lattice, leading to a stronger, more durable structure. To achieve this precipitation, metals and alloys need to be maintained at high temperatures for extended periods, hence the term “age hardening.”
In the case of PH (precipitation-hardened) stainless steels, heating between 900°F and 1200°F causes secondary phase particles to precipitate from the solid solution, creating a robust strengthening effect.
Advantages of Age Hardening
Age hardening offers several benefits, including:
- Increased tensile and yield strength
- Enhanced wear resistance
- Improved machinability due to structural uniformity
- Greater dimensional stability, reducing deformation over time
Industrial Applications of Age Hardening
Age hardening is essential in numerous industries for reinforcing metals and alloys. Common applications include:
- Strengthening alloys of aluminum, nickel, iron, and titanium
- Hardening critical components, such as gate valves, engine parts, shafts, gears, and plungers
- Reinforcing balls, bushings, turbine blades, fasteners, molding dies, and nuclear waste containers
- Treating aircraft components, processing equipment, and valve stems
Additionally, precipitation hardening can be combined with other processes, such as nitriding, to further reduce costs and enhance the resulting material properties, making it a versatile and cost-effective solution in material engineering.
Unique Capabilities
- Large furnace capacity (up to 48 feet)
- Vacuum levels to 1×10-6 torr
- Hardness testing
- On-site metallurgical test lab
- Conformance to AMS and MIL specifications
- Production or one-off jobs
- Cryogenic stabilization processing
Materials Processed
- 17-4PH/15-5PH Stainless Steel
- 17-7/15-7 PH Stainless Steel
- 13-8MO, A-286
- AM350/355
- Custom 450/455/465
- Maraging Alloys
- Inconel Alloy 718
- Inconel Alloy X-750
- And many others!
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