摘要
采用热模拟方法 ,模拟不同形态的针状铁素体、板条状铁素体和魏氏组织的试样 ,测定试样的断裂参量。发现不同形态的铁素体具有不同的解理断裂应力σf,而且韧性高的σf 也高 ;断口分析结果也表明 ,不同的铁素体具有不同的断口特征。低温下解理断裂的发生满足两个条件 :切应力达到临界的切应力 ;正应力达到解理断裂应力。
Steel specimens were thermally simulated to form needle ferrite, lath ferrite and widmanstatten structure. The fracture parameters were measured at low temperature and its fractographs were analysed. The results indicated that different forms of ferrite had different cleavage stress σ f and toughness (direct proportional) Fractographic analysis showed that different forms of ferrite had different fractographic characteristics. It was suggested that two conditions must be satisfied for cleavage fracture at low temperature in notched specimen, that is, the shearing stress ahead of a notch root must be larger than a critical value τ e; the principal stress σ yy must be larger than cleavage fracture stress σ f.
出处
《理化检验(物理分册)》
CAS
2000年第3期103-105,106,共4页
Physical Testing and Chemical Analysis(Part A:Physical Testing)