文档介绍：吉林大学
本科毕业设计翻译
学生姓名:*****
班级:*****班
学号:*****
学院:材料科学与工程学院
专业:材料成型及控制工程
指导教师:***** 副教授
2011年3月25日
Section 4 – Die Design and Construction Guidelines for HSS Dies
General Guidelines for Die Design and Construction
Draw Dies
Higher than normal binder pressure and press tonnage is necessary with . in order to maintain process control and to minimize buckles on the binder. Dies must be designed for proper press type and size. In some cases, a double action press or hydraulic press cushion may be required toachieve the necessary binder forces and control. Air cushions or nitrogen cylinders may not provide the required force for setting of draw beads or maintaining binder closure if . is of higher strength or thickness.
Draw beads for . should not extend around corners of the draw die. This will result in locking out the metal flow and cause splitting in corners of stamping. Draw beads should “run out” at the tangent of the corner radius to minimize pression in corners, as shown in figure 16 on page 47.
Better grades of die material may be necessary depending on the characteristics of the HSS, the severity of the part geometry, and the production volume. A draw die surface treatment, such as chrome plating, may be mended for outer panel applications.
Form and Flange Dies
Part setup in form and flange dies must allow for proper overbend on all flanges for pensation. Springback allowance must be increased as material strength increases; 3 degrees for mild steels, but 6 degrees or more for HSS.
Punch radii must be fairly sharp. 1t for lower strength steels. Higher strength steels may require larger radii, but keeping them as small as practical will reduce springback in the sidewalls.
Flange steel die clearance must be held to no more than one metal thickness clearance to reduce springback and sidewall curl.
Form and flange steels should be keyed or pocketed in the casting to avoid flexing.
Flange steels should be designed to wrap over