铸造法制备U形孔的抽芯过程设计及改进

Design and Improvement of Core-Pulling Process of U-Shaped Hole Prepared by Casting Method

为实现利用铸造法制备模具随形冷却水道,对采用抽芯法制备U形弯孔的过程进行了详细研究,分析了U形弯孔各部分抽芯力的特点,并建立了抽芯力模型。分析发现抽芯力为U形弯孔的两个直线部分和弯曲部分与孔壁基体间产生的最大静摩擦力,抽芯力的大小严重制约着U形弯孔的总长度。为此本文将碳纤维孔芯材料拆分为三部分分别抽出,实现分段式抽芯制备U形弯孔。利用分段式抽芯法制备的U形孔材料的圆整度和粗糙度较直接抽芯法没有明显变化,而弯孔长度可以提升1.5倍以上。

In order to realize the use of casting method to prepare follow-up cooling channel,this paper has carried out a detailed study on the process of preparing U-shaped curved hole by casting core-pulling method,analyzed the characteristics of the core-pulling force of each part of the U-shaped curved hole,and established the core-pulling force model.The analysis found that the core pulling force was the maximum static friction between the two straight part and the curved part of the U-shaped curved hole and the hole wall matrix,and the size of the core pulling force seriously restricted the total length of the U-shaped curved hole.For this reason,this paper split the carbon fiber core material into three parts and extracted them separately to realize the segmented core pulling to prepare the U-shaped curved hole.The roundness and roughness of the U-shaped hole material prepared by the segmented core-pulling method had no significant change compared with those of the direct core-pulling method,and the length of the curved hole was increased by more than 1.5 times.