vacuum hardening
Vacuum hardening is particularly well-suited for precision components with complex contours or large changes in cross-section.
Thanks to precise process control, the results are highly reproducible. This process has become indispensable in a modern heat treatment facility. In the first step, thermocouples are attached to the cleaned and properly loaded components to actively control the process. To prevent heating stresses and shorten the process time, the system is is heated to high temperatures convectively using nitrogen circulation.
The vacuum ensures that the workpiece does not react with gases in the furnace and retains its polished surface. As soon as the thermocouples signal that quenching should begin, nitrogen flows into the system in a precisely defined manner and cools the workpiece under positive pressure.
Once the optimal heating level has been reached, the ambient air is extracted.
The use of state-of-the-art technology that provides a particularly high quenching pressure of 10 bar , allows us to further optimize this proven heat treatment process.
KEY FIGURES FOR VACUUM HARDENING
Temperature:
up to 1,200°C
Oven size:
1,200 x 900 x 900 mm
Processing time:
24 hours or more
Max. load capacity*:
1,500 kg
*per batch for standard sizes and treatments
Advantages of VACUUM HARDENING
Clean surface
The result is a bright, metallic surface unaffected by scale formation, decarburization, or carburization.
Minimal dimensional change
Vacuum hardening is a process that causes minimal distortion, even though the laws of physics cannot be circumvented despite the vacuum.
Maximum process reliability
Seamless core temperature measurement enables extremely precise process control for optimal results.
Minimal post-processing
The workpieces remain bare metal during the hardening process, which reduces the effort required for finishing.
Components for Inert Gas Hardening:
- Tools (cutting, punching, forming, and shearing tools)
- Mold Inserts and Mold Plates (Tool and Mold Making)
- Stamps, Dies, and Cores
- Precision components with tight tolerances
- Components with sharp edges or large changes in cross-section
- Machinery and plant components with high dimensional accuracy requirements
- Medical and Precision Engineering Components
- Martensitic stainless steels (e.g., surgical instruments)
Inert Gas Hardening Process:
Vacuum hardening is primarily used for high-quality components that are susceptible to warping and require high precision. The process is particularly well-suited for alloyed and high-alloy steels, as these steels reliably harden to a martensitic structure even with slow gas quenching.
We look forward to hearing from you!
Please use our contact form or contact our sales team directly.
Silvio Stranek
Sales, Technical Consulting / Quotes (Upper Austria, Tyrol, Salzburg, Vorarlberg, Bavaria, South Tyrol)
Email. s.stranek@htr.at
Phone: +43 (0) 664 / 88 92 78 10
Thomas Stadlober
Sales, Technical Consulting / Quotes (Styria, Vienna, Lower Austria, Carinthia, Slovenia)
Email. t.stadlober@htr.at
Phone: +43 (0) 664 / 88 64 15 06
OTHER HARDENING PROCESSES
Protective gas hardening
In gas-protective hardening, the metal component is heated to the hardening temperature in a protective gas atmosphere and then rapidly cooled in an oil bath. Low-alloy materials are typically heat-treated in this manner.
induction hardening
In induction hardening, the areas to be hardened are heated using an induction current and then quenched with a water spray if necessary.
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OUR INDUSTRIES
Automotive industry
Aerospace
Medical technology
Tool and Machine Manufacturing
Your Questions, Answered
We have compiled a list of frequently asked questions to help you better understand our services.
What is vacuum hardening?
Vacuum hardening is a high-precision heat treatment process in which your component is heated to the hardening temperature in a vacuum and then quenched using nitrogen under positive pressure. This results in a bare metallic surface—free from scale formation, decarburization, or carburization. This process is particularly suitable for high-alloy materials.
What are the advantages of vacuum hardening?
Vacuum hardening offers several key advantages:
– Clean surface:Thebright metallic surface is achieved through vacuum treatment without oxidation.
– Minimal dimensional change:Thanks tolow-warpage quenching, dimensional accuracy is largely maintained—which is important for precision components.
– Maximum process reliability: Seamless core temperaturemeasurementusing thermocouples ensures extremely precise process control.
– Minimal post-processing:Thepolished surface significantly reduces the amount of work required for finishing operations.
– Reproducible results: Modern processcontrolensures high repeatability—even with complex components or large cross-sectional transitions.
– Environmental friendliness: No oil- or water-based mediaareused, which makes the process particularly clean.
How does the process work in detail?
After the components have been washed and properly loaded into the batch, thermocouples are attached. Heating is achieved through nitrogen circulation to minimize stress and save time.
Once the components have reached the optimal temperature throughout, a vacuum is created. This prevents chemical reactions with the surrounding environment and preserves the bare surface. During quenching, nitrogen is introduced at a defined overpressure—using our state-of-the-art technology, up to 10 bar —using our state-of-the-art technology—to ensure optimal, uniform cooling.
Which materials are suitable for vacuum hardening?
This process is particularly well-suited for high-alloy steels, martensitic stainless steels, tool steels, high-speed steels (HSS), powder metallurgy steels, and other materials that require high levels of hardness, precision, and surface finish.
Which components can be vacuum-hardened?
Typical applications include precision parts with tight tolerances, tools, molds, gears, bearing components, cutting and forming parts, and components with large cross-sectional transitions. The process is indispensable in modern industry—for example, in tool and mold making.
What are the key technical specifications of vacuum hardening?
– Maximum temperature:up to1,200 °C
– Oven dimensions:1,200 × 900 × 900 mm
– Turnaround time: 24 hoursor more
– Maximum load weight per batch:up to1,500 kg (standard sizes/finishes)