Introduction to Precision Casting
<a href="https://casting-china.org/precision-casting-services/">Precision Casting</a>, also known as investment casting or lost-wax casting, is a specialized manufacturing process used to produce highly accurate and complex metal components. This technique is classified under "special casting" rather than conventional casting methods due to its ability to achieve tight tolerances and superior surface finishes.
Key Process Steps
The workflow of investment casting can be summarized into five stages:
Pattern Creation: Wax or synthetic materials are injected into molds to form precise replicas of the final part. These patterns are then assembled into clusters (a process called "组树" or tree assembly).
Shell Building: The wax cluster is repeatedly dipped into ceramic slurries and stuccoed with refractory materials (e.g., zirconia or silica) to form a multi-layered shell. After drying, the shell is heated to melt out the wax, leaving a hollow mold.
Pouring: Molten metal (e.g., stainless steel, aluminum, or titanium alloys) is poured into the preheated ceramic mold. Techniques like vacuum casting or centrifugal casting may enhance filling accuracy.
Post-Processing: The solidified casting is removed via vibration or chemical means. Additional steps include shot blasting, machining, and heat treatment to meet dimensional and mechanical requirements.
Inspection: Rigorous checks—such as wax inspection, dimensional measurement, and non-destructive testing (NDT)—ensure compliance with specifications.
Applications and Advantages
Investment casting is widely used in aerospace (e.g., turbine blades), medical devices (e.g., orthopedic implants), and automotive industries (e.g., engine components). Its advantages include:
Ability to produce intricate geometries with thin walls (as low as 2 mm).
Superior surface finish (Ra 1–3 μm), reducing the need for machining.
Compatibility with high-performance alloys like Ti-6Al-4V and superalloys.