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以宝钢生产的14种规格和牌号的钢板为研究对象,对其V弯成形特性进行了研究,通过单向拉伸实验,获得材料的基本力学性能,分析了试验材料的V弯回弹规律。试验结果表明,材料存在正、负回弹,相同弯曲角度下随弯曲半径增大,回弹量增加且趋向正回弹,在相同弯曲半径下,弯曲角度增大,回弹量减小且趋向负回弹,可通过调整弯曲角度或弯曲模具圆角大小来可合理控制零件回弹;在相同厚度条件下,当材料抗拉强度大于600 MPa时,回弹量显著增大;在相同强度条件下,回弹量随弯曲角度的增大而趋向负回弹,同时随着弯曲半径的变大,回弹量随材料厚度产生的差异趋缓,并趋向正回弹;980 MPa强度级别材料中材料厚度越小,不同弯曲半径下的回弹量差异变大;厚度相同的情况下,QP钢和MS钢的回弹量比DP钢更趋向于正回弹;数值拟合发现,回弹角度随R/T值的增大而增大,且经历一个由负到正的过程。随着弯曲角度的增大,拟合曲线下移且斜率变小,只有当R值足够大时才会出现正回弹。
Based on the 14 specifications and grades of steel plate produced by Baosteel, the V-bend forming properties were studied. The uniaxial tensile test was conducted to obtain the basic mechanical properties of the material, and the V-bend rebound laws of the tested materials were analyzed. The experimental results show that the material has positive and negative rebound, the bending radius increases with the same bending angle, the rebound increases and tends to rebound, the bending angle increases with the same bending radius, the rebound decreases and tends to When the tensile strength of the material is greater than 600 MPa, the springback will increase remarkably. Under the same thickness condition, the rebound amount will increase significantly. Under the same strength condition , The rebound amount tends to rebound with the increase of bending angle. At the same time, with the increase of bending radius, the difference of rebound amount with material thickness tends to slow and tends to rebound; in 980 MPa strength grade material The smaller the material thickness, the bigger the difference of springback under different bending radius. When the thickness is the same, the springback of QP steel and MS steel tends to rebound more than that of DP steel. The numerical fitting shows that the rebound angle As R / T value increases and increases, and go through a negative to positive process. As the bending angle increases, the fitted curve moves downward and the slope becomes smaller. Positive rebound occurs only when the value of R is large enough.