Heat Treatment Jigs - Lost Wax
1. Advantages of Lost Wax
Lost wax casting offers high dimensional accuracy and reproducibility, enabling the production of complex shapes. This expands design freedom and allows for appropriate heat treatment. Various heat-resistant cast steels can be selected, providing optimal materials and shapes for different applications. Lost wax products are suitable for applications with relatively large production quantities, helping to reduce manufacturing costs.
2. Lost Wax Manufacturing Process
The manufacturing process of lost wax includes the following steps:
| No | Process | Description |
| 1 | Wax Injection | Create wax patterns using precision molds |
| 2 | Assembly | Combine multiple wax patterns into a single unit, an efficient method for producing multiple parts at once. |
| 3 | Shell Building | Apply ceramic layers over the wax model to create a durable shell capable of holding molten metal during casting. |
| 4 | Burn Out/Dewax | Melt and remove the wax within the ceramic shell, forming a hollow shell for the next process (casting). |
| 5 | Gravity Pouring | Pour molten metal into the ceramic shell, allowing precise casting by filling all corners of the shell. |
| 6 | Knock Out | Break the ceramic shell to extract the casting, revealing the finished metal parts. |
| 7 | Cut Off | Separate the casting into individual parts. |
| 8 | Finished Casting | Perform finishing tasks such as deburring and polishing to complete the final product. |
3. Comparison of Heat-Resistant Materials (Heat-Resistant Cast Steel) Used in Lost Wax
Comparison between heat-resistant materials used in lost wax and stainless steel welded jigs:| No | Item | Stainless Steel Welded Jig | Lost Wax: Heat-Resistant Jig |
| 1 | Base Material | SUS304, 310S, etc. | SCH13/HH, SCH21/HK30, SCH22/HK40, etc. |
| 2 | Structure | Mixed base material, weld metal, heat-affected zone | Uniform |
| 3 | High-Temperature Deformation | Deforms easily at high temperatures | Resists deformation at high temperatures |
| 4 | Correction | Easy to correct at room temperature (40% elongation) | Difficult to correct at room temperature (8% elongation) but resists high-temperature deformation |
| 5 | High-Temperature Cracking | Prone to cracking at welds | Less prone to cracking if no casting defects |
| 6 | Design Flexibility | Limited design freedom compared to lost wax | High design flexibility with lost wax precision casting |
| 7 | Wood/Metal Mold | Not required | Required |
4. Heat Treatment Furnaces Using Lost Wax Products
Lost wax products are used in various heat treatment furnaces, such as:
- Tray Pusher Furnace: Transports products using a pusher mechanism. Suitable for continuous heat treatment and mass production.
- Roller Hearth Furnace: Transports products on rollers inside the furnace. Suitable for continuous heat treatment and mass production.
- Batch Furnace: Involves batch processing with horizontal furnaces, suitable for flexible manufacturing of small lots with multiple varieties.
- Pit Furnace: Vertical furnace suitable for deep heat treatment, also flexible for small lot production with multiple varieties.
5. Heat Treatment Products Made with Lost Wax
Examples of heat treatment products made with lost wax include:
- Trays: Used to evenly heat parts inside the heat treatment furnace. Lost wax trays can realize complex shapes.
- Baskets: Used to heat treat small parts or multiple parts at once. Lost wax baskets can achieve a mesh structure.
- Grids: Used to fix and stabilize the position of parts, especially for large parts. Lost wax grids are uniformly spaced and provide high strength and heat resistance.
- Pillars: Used to adjust the height of products or other jigs (grids or baskets) for uniform heating. Lost wax pillars can be made in various heights and shapes.
- Hanger Bars: Used to hang parts for heating, particularly suitable for long parts.
6. Consultation on Lost Wax
For consultations regarding lost wax, please contact TWC. We offer optimal proposals leveraging our extensive experience and expertise. Feel free to inquire about any questions or estimates.
