先进高强双相钢拉延回弹实验研究

Springback experimental study on stretch bending of advanced high strength dual phase steel

基于企校联合自主研制的拉延弯曲实验机平台,分别研究了武钢590 MPa级和780 MPa级双相钢的拉延弯曲回弹性能。通过不同弯曲半径模拟不同冲压模具圆角半径,同时以不同名义张紧力（0.2-1.2）模拟冲压压边力,分析讨论了两种材料的成形及回弹性能;利用光学应变测量仪分析了两种材料在拉延弯曲区域和弯曲、反弯曲两个区域的应变量。结果表明,同样条件下,780 MPa级双相钢的回弹量要略大于590 MPa双相钢;同时,弯曲半径越大、张紧力越大,两种材料的回弹量和应变越小;反之亦然。

The springback property of stretch bending for WISCO advanced high strength dual phase steel HC590 DP and HC780 DP was researched based on the stretch bending test equipment designed and manufactured by WISCO and its college copartners.The formability and springback property of two materials were studied by varying the bending radius to simulate the die radius and the nominal tension force（0.2-1.2） to simulate the blank holder force during stamping experiments.In addition,the plastic strain in the typical stretch bending and bending-and-unbending areas of these specimens were measured and analyzed by an optical scanning measurement system.In conclusion,the springback of steel HC780 DP with higher strength is larger than that of steel HC590 DP under the identical condition.At the same time,the larger the bending radius and tension force,the smaller springback and plastic strain,and vice versa.