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平整和应变时效对于低碳沸腾钢板成形特性的影响已在单轴抗张、双轴拉伸成形和深冲试验中作了研究。结果表明,金属变数对于性能的影响取决于特殊试验所造成的条件。平整1.2％对于单轴抗张延伸率具有很小的效应,但却降低了拉伸成形性和深冲性。平整1.2％之后的应变时效降低了拉伸性能,但不影响深冲性。5％的平整率无论是直接地还是在依次时效结果中都导致更为严重的拉伸性能的下降。在包括形变的较大拉伸成形部件操作中,轧制压下率5％之后的应变时效也降低了深冲性能,但是如果用小冲头半径的冲头进行冲压的话,它基本上没有什么效应。一般地说,在冲压速度为1至100呎/分的范围内,平整和应变时效不会极大地改变所观察到的速度效应。如果在不同的操作中考虑到与破断有关的应变硬化范围,所得结果的定性解释就可用加工硬化行为中所观察到的变化值来说明。但是从简单的机理试验预测深冲容量存在特殊的困难。因为冲压性质对导致杯的拉伸成形区和冲压区形态有关变化的加工过程和材料变数是灵敏的。但是,它对塑性特点的一般变化是不灵敏的。因此,其结论还是支持用摸拟试验来比较深冲性能。
The effects of formation and strain aging on the forming characteristics of low-carbon steel sheets have been studied in uniaxial tensile testing, biaxial stretching forming and deep drawing tests. The results show that the influence of metal variables on performance depends on the conditions caused by the special test. A flatness of 1.2% had little effect on uniaxial tensile elongation, but reduced draw formability and deep drawability. Strain aging after a flattening of 1.2% reduces tensile properties but does not affect drawability. A flattening of 5% resulted in more severe degradation of tensile properties, either directly or in sequential aging results. Strain aging after 5% rolling reduction also reduces deep drawability in the operation of larger stretch formed parts that include deformation, but is essentially negligible if punched with a small punch radius punch effect. In general, smoothing and strain aging do not significantly change the observed velocity effects at ram speeds of 1 to 100 feet per minute. If the range of strain hardening associated with rupture is taken into account in different operations, the qualitative interpretation of the results obtained can be illustrated by the observed changes in work-hardening behavior. However, there are particular difficulties in predicting deep-drawing capacity from simple mechanistic tests. Because the stamping properties are sensitive to the process and material variables that cause changes in the cup forming and stamping zone morphologies. However, it is insensitive to the general changes in plasticity. Therefore, the conclusion is still supported by the use of simulation tests to compare the deep-drawing properties.