摘要
采用Ｈｏｐｋｉｎｓｏｎ单压杆技术对４０ＣｒＮｉＭｏＡ钢单边平行双裂缝试样进行高速剪切加载，得到了在不同动态高加载率时的动态断裂起始韧性。实验表明，在实验的加载率范围内，沿原裂纹方向扩展的动态剪切型断裂存在两种不同的断裂模式，分别称为常规的韧性剪切断裂模式和绝热剪切型断裂模式。前者的断裂韧性随加载率的提高而增大，而后者的断裂韧性则随加载率的提高而减小。根据对这两种断裂行为及其相互转变的实验结果的分析探讨，认为存在一个临界应力强度因子率Ｋ·ｃΠｄ，它表征两种断裂模式发生转变的条件。
A single Hopkinson pressure bar technique was used for testing 40CrNiMoA plate specimen with two parallel edge cracks under high velocity loading.The dynamic mode Ⅱ fracture toughness for initiation were studied at a relatively wide range of high loading rate.The results show that the two markedly different types of fracture pattern exist even for shear fracture,i.e.,the conventional ductile shear fracture and adiabatic shearing fracture.A transition of failure mode occurs at a critical loading rate.The dynamic fracture toughness K Ⅱd increases with increasing loading rate when the failure is controlled by the conventional shear fracture,while the K Ⅱd decreases with increasing loading rate when it is predominated by adiabatic shearing fracture.
出处
《爆炸与冲击》
EI
CAS
CSCD
北大核心
1999年第3期222-228,共7页
Explosion and Shock Waves
基金
中国工程物理研究院流体物理研究所冲击波物理与爆轰物理实验室资金资助
浙江省教委基金
关键词
动态断裂韧性
Ⅱ型
裂纹
绝热剪切
合金钢
dynamic fracture toughness,mode Ⅱ crack,adiabatic shearing,steel alloy
