Lowering temperature window of rolling and large strain accumulation is basic condition for exceeding of critical strain for dynamic recrystallization to refine austenite grain size.

为了获得足够的应变积累来克服动态再结晶的临界应变，低温大变形量的变形是基本条件。

youdao

Plane strain fracture toughness (KIc). The critical value of the stress intensity factor (i. e., at which crack propagation occurs) for the condition of plane strain.

平面应变断裂韧性(KIc)：平面应变条件下应力强度因子的临界值(即达到该值时裂纹发生扩展)。

youdao

China Central Television and other major media say four new people living in different cities in Jiangsu province are in critical condition with H7N9, a strain of bird flu that was previously unknown in humans.

BBC: China media: Concerns over bird flu