关于收缩率和延伸率间偏差和颈缩分析I

Analysis on Deviation and Necking Formula between the Elongation & Reduction I

摘要: 根据收缩率和延伸率间密度不变时的公式可以推倒出它们之间颈缩的不等式。曲线很好地说明了它的走势。由偏差关系得出在小于14%时收缩偏差较好，在中间一段延伸偏差较好，大于一定值收缩率偏差又变好的规律。在64%偏差率时收缩率的值小于延伸率，它的真实性高1.32倍以上，最大偏差为1.64。推导出(√S₀)³-S√S₀+S₀-2S<0等两个公式为颈缩发生推倒公式。据文献统计收缩率值在大于25%时比较多，而延伸率则在30%以下较多。双晶由剪应力引起，转位由拉应力引起。

Abstract: According to density invariability of elongation and reduction, we can deduce the compare mathematical relation of them. Equations to cause necking and deviation routes are gained. From deviation relations, we observe that in the case of smaller than 0.14 reduction deviation it will become good to compare with elongation one. In the case of deviation bigger than certain value reduction one of 0.64 will be good too. They are above 1.32 times good in this value. The maximum deviation is 1.64. (√S₀)³-S√S₀+S₀-2S<0 etc. two formulas are the necking equation here. According to literature statistic, the reduction is more above 25% while elongation is more below 25%. The twin is caused by shear stress, and dislocation is caused by tensile stress.