本研究旨在探討在熔模鑄造過程中改善精密鑄造的尺寸精度的策略。在實踐中，精密鑄造中的尺寸改進通常涉及修改主模的尺寸。這些修改通常需要重製昂貴的主要模具。為了解決這個問題，我們提出了一種兩階段射蠟方法，通過降低蠟模在射蠟後的收縮率，使產品更接近設計尺寸，而無需重新製作主模具。我們為內部粗略輪廓製作了一個小模具，並採用兩階段射蠟過程來改善產品的尺寸。我們的研究表明，與傳統的直接射蠟方法相比，兩階段射蠟方法更接近產品的設計尺寸。 從整體尺寸的角度來看，方案A與設計尺寸之間的平均偏差為0.9毫米。然而，兩階段射蠟方法將原始方案的平均偏差降低到0.65毫米，並將平均偏差進一步降至0.25毫米，與設計尺寸相比。這表明兩階段射蠟方法，透過降低歧管在製造流程過多的收縮變形，收縮率由0.043降低到0.030，使產品更接近設計尺寸。 此外，本研究比較了快速鑄造方法與精密鑄造方法，並發現在尺寸收縮方面存在相似性。這表明可以在管道開發時間表中使用快速製造技術，無需金屬模具即可在幾天內生產蠟型。這有助於在開發時間表中減少金屬模具生產所需的時間和成本，同時先行了解鑄造後產品變形以及可能出現的缺陷。 本研究的主要貢獻有兩個方面。首先，我們提出了使用兩階段射蠟方法來提高尺寸精度的可行性。其次，我們展示了從快速鑄造3D打印PLA模型和熔模鑄造獲得的最終產品之間的一致性，凸顯了快速鑄造在管道開發中的價值。 ;This study investigates strategies to improve dimensional accuracy in precision casting during the investment casting process. In practice, dimensional improvement in precision casting typically involves modifying the dimensions of the main mold. These modifications often require costly redevelopment of the main mold. To address this issue, we propose a two-stage wax injection method, which innovatively enhances the wax pattern dimensions without the need to remake the main mold. Instead, a small mold is created for the internal rough contour, and a two-stage wax injection process is employed to improve the dimensions of the manifold product. Our research reveals that the two-stage wax injection method exhibits better dimensional accuracy compared to the traditional direct wax injection method. From an overall dimensional perspective, the average deviation between Scheme A and the design dimensions is 0.9 millimeters. However, the two-stage wax injection method reduces the average deviation of the original scheme to 0.65 millimeters, and further decreases the average deviation to 0.25 millimeters compared to the design dimensions. This indicates that the two-stage wax injection method, by reducing excessive shrinkage deformation in the manufacturing process of the manifold, lowers the shrinkage rate from 0.043 to 0.030, bringing the product closer to the design dimensions. Additionally, this study compares rapid casting methods with precision casting methods and identifies similarities in terms of dimensional shrinkage. This suggests that rapid manufacturing techniques can be employed in the manifold development timeline, enabling the production of wax patterns within a few days without the need for metal molds. This helps to gain early insights into the casting shrinkage rate while reducing the time and costs associated with metal mold production during the development timeline. The primary contributions of this study are twofold. Firstly, we propose the feasibility of using the two-stage wax injection method to enhance dimensional accuracy. Secondly, we demonstrate the consistency between the final products obtained from rapid casting 3D printed PLA models and investment casting, highlighting the value of rapid casting in manifold development.
