Comparision of Warm Deep Drawability of Square Cups Using Circular Clad Sheet Metals

원형 클래드 판재를 이용한 정사각컵 온간 디프 드로잉성 비교

This study was carried out to investigate the warm deep drawability of square cups of clad sheet metals, by changing temperatures of die and blankholder and blank materials. Two kinds of clad sheet metals, STS304-A1050-STS304 and STS304-A1050-STS430 were chosen for experiments. The relative drawing depth of STS304-A1050-STS304 clad sheet was increased up to 4.4 at $150^{\circ}C$ that was $29\%$ higher than at room temperature, whereas STS304-A1050-STS430 material was improved to 3.65 at $120^{\circ}C$ which was $16\%$ better than at room temperature. In addition, comparison of wall thickness and hardness of a warm drawn cup with those of room temperature showed more even distributions. Therefore, warm forming technique was confirmed to ive better results in deep drawing of stainless clad sheet metal.