计算时出现如下状况如何解决

在计算过程中出现了满屏的如下信息，不知道是什么意思，盼望高手指点。是由于变形网格变形太大吗?
（我做轧钢模拟，前几道次计算都没问题，从第六道次开始出现这个问题，设置和以前一样，不能正常计算了。）
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
More illegal flow stresses .....
138 0.4993858552E+04 0.2080288825E-01 0.1092725162E+00 1.176
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
More illegal flow stresses .....
139 0.4994801601E+04 0.2079739315E-01 0.1097623941E+00 1.156
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
Warning: failure in log extrap. of flow stress
More illegal flow stresses .....