设计锌基合金模具中表面质量应注意的问题.docx

1、设计锌基合金模具中表面质量应注意的问题 设计锌基合金模具中表面质量应注意的问题为降低产品成本，获得较好的表面质量，采用锌基合金模具拉深，模具结构如图2所示。但是锌基合金材料较软，仅表面有一层较硬层(硬度为hb100115)，故模具寿命较低。据情况看，拉深不复杂的冲件，坯料为08钢、料厚为1.0mm，凹模圆角半径rd5mm，其模具寿命仅600件。如何提高锌基合金拉深模的寿命，在拉深件设计时应采取什么具体措施。In order to reduce the product cost, achieve better surface quality and using zinc base alloy d

2、ie drawing, die structure is shown in figure 2. But the zinc base alloy material is relatively soft, only the surface has a layer of hard layer (hardness of hb100 115), so the die life is low. According to the situation, drawing not complex salt pieces, billet is 08 steel, material thickness is 1.0

3、mm, concave die radius rd = 5 mm, the mould life 600 pieces only. How to improve life of the zinc base alloy deep drawing mould, in what specific measures should be taken when drawing a design. 图2拉深模Figure 2 deep drawing mould 1.凹模2.凸模3.压边圈4.导板2. 1. The concave die punch 3. Pressure rim 4. Guide 锌基合

4、金拉深模寿命较低的主要原因是模具的工作表面(凸模表面，压边面和凹模圆角部分)产生磨损和拉伤所致。Investigation and analysis this factory production situation can be seen, zinc base alloy deep drawing die life is the main reason for the lower is the job of the mold surface (surface of the punch and blank holder and die round corner part) caused by

5、wear and tear. 1.模具磨损1. Mould wear and tear 模具工作表面的磨损主要产生于两种情况：Wear on the surface of the mould work is mainly produced in two cases: (1)坯料成形时产生必要的塑性流动对模具工作表面的磨损。When necessary (1) the blank forming on the surface of the plastic flow in mould work wear. 为实现拉深成形，坯料产生必要的塑性流动，沿压边面经过凹模圆角处流入凹模。由于坯料的塑性流动，

6、坯料和压边面之间以及坯料和凹模圆角之间产生摩擦而引起模具磨损。这种磨损是不可避免的，但应设法减小。可通过以下两个方面减少磨损：To achieve deep drawing, blank to produce the necessary plastic flow, the blank holder surface after die fillet area flow into the die. Plastic flow due to the blank, blank and blank holder surface between billet and die round corner cau

7、sed by the friction between mold wear. The wear is unavoidable, but should try to reduce. Reduce wear can be through the following two aspects: 1)在拉深件设计时，采取措施减小坯料向凹模内塑性流动的阻力1) during deep drawing parts design, take measures to reduce billet resistance to plastic flow into the die a.选用较大凹模圆角半径。例如拉深08

8、钢，料厚t1.0mm时，凹模圆角半径rd10t。A. choose larger die radius. Such as deep drawing steel 08, t = 1.0 mm material thickness, die radius rd = 10 t. b.压边面采用正向倾斜的型式(图3)，这有利压边面材料向凹模内流动。B. blank-holder surface adopt positive sloping pattern (figure 3), the positive pressure side surface of the material to flow int

9、o the die. 图3In figure 3 1.凸模2.压边圈3.凹模1. Punch 2. Pressure to coil (3) die c.拉深件侧壁部设计成倾斜的型式(图4)，这使凸模和凹模之间的间隙在拉深开始时较大，逐渐减小，直到拉深终结时才形成。这才有利于压边面材料向凹模内流动。C. the side wall of drawing pieces designed to tilt the pattern (figure 4), the clearance between the convex mold and concave die at the beginning of

10、the drawing is bigger, decreases, until at the end of the drawing to the form. This is conducive to the blank holder surface materials to flow into the die. 图4Figure 4. 1.凸模2.压边圈3.凹模1. Punch 2. Pressure to coil (3) die d.减小拉深深度，亦可使压边面材料容易向凹模内流动。D. decrease the drawing depth, may also make the blank

11、holder surface material easy to flow into the die. 2)保证坯料压边面沿凹模周边各处材料向凹模内流动尽量均匀。2) ensure that blank blank holder face around everywhere along the concave die material to flow into the die as far as possible even. 在拉深过程中，压边面相邻区坯料向凹模内流动应没有突变。不均匀的塑性流动会导致凹模圆角部分局部磨损过大而减少整个凹模的寿命。生产中拉深圆筒件的凹模寿命比拉深盒形件(非轴对称件

12、)的凹模寿命高，水性油墨就是因为拉深非轴对称件时，材料向凹模圆角内流动不均匀，导致局部磨损过大。为保证压边面材料向凹模内流动的均匀性，可采取以下措施：In deep drawing process, blank holder surface electrodes in the adjacent area to flow into the die should be no mutations. Uneven plastic flow leads to die the rounded part of the local excessive wear and reduce the die life.

13、 Deep drawing of cylinder parts in the production of the die life of deep box (non axisymmetric parts) of long service life of the die, it is just because of the deep drawing of axisymmetric parts, the material flow within the die corner are uneven, cause partial wear is too large. In order to ensur

14、e the blank holder surface uniformity of material to flow into the die, can take the following measures: a.改变凹模圆角半径。覆盖件拉深，其整个凹模的圆角半径各处是不同的，应根据拉深件的形状作合理设计。在压边面坯料容易流入凹模处的凹模圆角半径应小于压边面坯料难于流入凹模处的凹模圆角半径。矿用风机不同的凹模圆角半径也可以通过模具试冲时得到。A. change the die fillet radius. Covering parts, deep drawing, the radius of

15、concave die is different everywhere, the reasonable design should be done according to the shape of the deep drawing parts. On the blank holder surface billet is easy to flow into the die radius should be less than the pressure of the die edge surface of the billet is difficult to flow into the die

16、radius of concave die. Different radius of concave die can also through the mold try when rushing to get. b.压边面上布置拉深筋。布置和调整拉深筋是最有效的控制压边面坯料向凹模内流动的方法。可沿拉深件周边布置一圈整筋。在直边处和内凹曲边处布置短筋，使这部分压边面材料向凹模内流动减慢。B. blank-holder surface drawbead layout. Drawbead arrangement and blank holder face is the most effective

17、 control method of blank to flow into the die. But along the deep drawing pieces decorate a circle surrounding the whole bar. In the straight edge and concave curved edge in short muscle, make this part of the blank holder surface material to flow into the die. (2)拉深过程中坯料沿凸模表面产生相对窜动，而使凸模表面磨损。(2) in

18、the process of deep drawing billet relative channeling move along the surface of the punch, and make the punch surface wear. 坯料沿凸模表面产生相对凸模的窜动是拉深成形不需要的，应避免产生。拉深过程中，坯料应紧贴在凸模表面随凸模一同运动。产生这种窜动的原因是坯料压边面相对部分向凹模内进料速度不一致。拉深件设计时，可采取以下措施来避免坯料相对凸模窜动：Billet along the surface of the punch to punch up move is rela

19、tive to deep drawing dont need, should avoid to produce. Deep drawing process, blank should be close to in the punch surface movement with punch. Produce this channeling dynamic blank blank holder face is the cause of the relative parts to die within the feed speed is inconsistent. When deep drawing

20、 a design, can take the following measures to avoid the billet relative punch up move: 1)压边面设计应使拉深凸模顶部与坯料大面积接触，为此拉深件压边面设计应平行拉深件的底部(图5)。1) the blank holder surface design should make deep drawing punch at the top of the contact with the blank area, therefore deep drawing press edge parallel to the pl

21、ane design should be the bottom of the deep drawing parts (figure 5). 2.模具拉伤2. Mold strain 锌基合金模具工作面容易拉伤产生拉痕，这是因为合金材料仅表面有一层硬层，一旦表面某部分硬层磨损内部较软材料暴露出来，磨损将加剧形成拉痕。这种情况产生在拉深过程中压边面坯料起皱的地方。因此，锌基合金模具拉深防皱是很重要的。在拉深件设计时，可采取以下措施防止模具工作面拉伤：Zinc base alloy die face easier to produce strain marks, and this is becaus

22、e the metal material surface has a layer of hard layer only, once a part surface hardened layer wear exposed internal soft materials, the wear will aggravate form mark. This kind of situation to produce blank wrinkling on surface of the deep drawing process of medium voltage side. Therefore, zinc ba

23、se alloy die drawing blank is very important. When deep drawing a design, can take the following measures to prevent the mold working strain: (1)压边面设计应平滑。覆盖件拉深其压边面多数为曲面形状，压边面由压边圈压紧在凹模压边面上不应形成皱纹和折痕，各部分应平滑过渡。(1) the blank holder surface design should be smooth. Covering parts deep drawing the blank ho

24、lder surface to surface shape, the blank holder surface by the blank holder pressure at the edge of the concave die circle should not form wrinkles and creases, on the surface of the parts should be smooth transition. (2)减小拉深深度。压边面设计应使拉深深度减小。拉深深度愈浅，所需毛坯尺寸愈小，拉深时不容易产生起皱现象。(2) reduce the depth of deep

25、drawing. Blank-holder surface design should reduce depth of deep drawing. Deep drawing depth more shallow, the blank dimensions needed for the small, deep drawing is not prone to wrinkling. (3)布置拉深筋。在凹模口部压边面处布置拉深筋，虽不能防止压边面坯料起皱，但是压边面上产生的活皱在通过拉深筋时可被拉深筋轧平，防止凹模圆角处拉伤。(3) the drawbead layout. At die mouth blank holder surface, drawbead layout cannot prevent the electrodes in the blank holder surface wrinkling, but produced by the blank holder surface wrinkles through drawbead draw bead can be smooth, rounded to prevent concave die strain.