Heat Treatment Jigs - Lost Wax

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.