剪切速度对棒料剪切断面质量的影响  

Influence of shearing speed on section quality for bar shearing

作　　者：李继威[1] 胡成亮[1] 赵震[1] 李忠明 

机构地区：[1]上海交通大学塑性成形技术与装备研究院,上海200030 [2]宁波思进机械股份有限公司,浙江宁波315101

出　　处：《锻压技术》2016年第8期122-126,共5页Forging & Stamping Technology

基　　金：国家科技重大专项(2013ZX04002081)

摘　　要：棒料剪切工艺是多工位冷镦机的第1步工序,坯料的断面质量对后续挤压工序有着重要影响。研究径向不夹紧条件下的棒料剪切工艺,将棒料剪切分为4个过程:初始阶段、棒料倾斜、弹塑性变形和裂纹产生及扩展,分析了每个过程的特点。以20Cr为试验材料,在剪切速度分别为200,400,600和800 mm·s^(-1)的条件下进行棒料剪切试验。定性分析各剪切速度条件下的坯料端断面和棒料端断面的断面形貌,发现随着剪切速度的增大,坯料端光亮带比例逐渐减小,棒料端断面不平度明显减小;定量比较各剪切速度条件下的坯料端断面和棒料端断面的椭圆度与断面倾角,发现随着剪切速度的增大,断面椭圆度逐渐减小,棒料端断面倾角基本不变。The bar shearing process is the first step of multi-station cold forming machine,and section quality of the billet has a great influence on the next forming steps. The bar shearing process without radial clamping was studied,and the shearing process was divided into four stages including original stage,bar inclining,elastic-plastic deformation and crack initiation-propagation. Then,the characteristic of every stage was analyzed. Furthermore,for the material 20 Cr,the shearing experiments were carried out under the different shearing speed 200,400,600 and 800 mm·s- 1respectively,and the characteristics of both billet section and bar section were qualitatively analyzed. It is found that the burnished surface ratio of billet end and section roughness of bar end decrease obviously with the increase of the shearing speed. After comparing the ovality and section angle of billet section and bar section,it is found that the ovality decreases with the increase of shearing speeding,while the section angle is constant.

关 键 词：剪切 剪切速度 断面质量 多工位冷镦机 棒料 

分 类 号：TG306[金属学及工艺—金属压力加工]