冷弯试验方法是衡量钢板在一定条件下的塑性变形性能或冲压性能优劣的一种方法。这种方法是金属板材一种主要的工艺试验方法,应用很广。不仅用来衡量钢板塑性和韧性的好坏,而且还是检验钢板表面质量优劣的一种方法。在汽车生产实践中,发现过去的冷弯试验结果,往往不能反映出生产上冲压性能的好坏和冲压件废次品率的高低。如冲压解放牌载重汽车车架大梁用的厚度为6毫米的16锰钢板,在不同时期对不同批号的钢板进行冷弯试验(试验样品宽度为12毫米,弯心直径d等于公称板厚α),结果虽然均为完好(即按现行标准规定弯至180°不得有裂纹为合格),但在生产中另 Cold-bend test method is a measure of the plastic under certain conditions of plastic deformation performance or punching a pros and cons of a method. This method is a major test method of metal plate, a wide range of applications. Not only used to measure the plasticity and toughness of steel is good or bad, but also to test the quality of the steel surface of a method of quality. In automobile production practice, it is found that the results of the past cold-bend test often can not reflect the quality of the stamping performance of the production and the level of scrap defective rate of stamping parts. Such as stamping Jiefang license truck frame girder with a thickness of 6 mm 16 manganese steel plate in different periods of different batches of cold-rolled test (test sample width of 12 mm, c-bending diameter equal to the nominal plate thickness α) , Although the results are intact (ie, according to the current standard bending to 180 ° can not be cracked as qualified), but in the production of another