平板单面剥层X射线应力测定中的幂级数校正

在具有矩形截面的平板或棒材的单面剥层 X 射线应力测定中,可以用幂级数来分段近似沿层深变化的剥离面的实测应力曲线,从而计算剥层所产生的附加应力,求得原始真实应力沿厚度方向的分布。文中给出了计算应力校正量的公式,并且用两个实测例说明,用项数不多的幂级数来近似实测曲线,就能得到足够高的近似程度.这种近似对计算结果的影响远小于 X 射线应力测量误差的影响.

Power Series Correction for Single-Side Removal of Plate in X-Ray Stress Determination

In X-ray stress determination for single-side removed(flat)plate or bar with rectangular cross-section,the curve,which represents the measured stress varying with depth,can be sectionally approximated by a power series.Consequently,the additional stresses caused by the removal can be evaluated,and finally the true stress varying with depth before the layers were removed can be obtained.Formulas used to evaluate correc- tions for stress have been derived.Two examples show that a few terms of power series can provide us an approximation good enough for measured stress curve.The error caused by approximation is far less than that arising from X-ray stress determination.