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众多结晶体在低温环境下呈现解理断裂，在高温环境下呈现塑性断裂在过渡温区，解理断裂的应力随温度增加而增加，反映了屈服应力的下降以及裂纹尖端区塑性的相应增加．裂尖塑性可钝化裂纹并因塑性区中的压应力而屏蔽裂纹本文简短评述了脆一韧转变模型在该模型中，计算屏蔽效应的塑性区是由位错的产生、运动和相互作用形成的，这些位错均在含裂尖的滑移面上运动，并且服从速度／应力／温度定律.对模型在实验结果中的应用也进行了讨论．
Many crystals exhibit cleavage fracture at low temperature and show plastic fracture at high temperature. In the transitional temperature region, the stress of cleavage fracture increases with temperature, reflecting the decrease of yield stress and the corresponding increase of plasticity at crack tip. Crack Tip Plasticity Passivates Cracks and Shields Cracks Due to Compressive Stress in the Plastic Zone A brittle-ductile transition model is briefly reviewed in this paper. In this model, the plastic zone in which the shielding effect is calculated is formed by the generation, movement, and interaction of dislocations These dislocations all move on the crack-tip slip surface and obey the laws of velocity / stress / temperature. The application of the model to the experimental results is also discussed.