高强度低合金钢的冷脆转变与加载速度的关系

EFFECT OF LOADING RATES ON DUCTILE-BRITTLE TRANSITION BEHAVIOR OF HIGH STRENGTH LOW ALLOY STEELS

对新发展的HQ80C和HQ100钢的动态加载断裂韧性J_(id)进行了测定,用应变片法确定启裂点。引入了一个韧脆转变的动力学模型来解释试验结果并对结果进行了讨论。

In the present study the crack initiation fracture toughness J_(id) of HQ80C and HQ100 steel test was carried out by using the strain gauge method. The results of the dynamic toughness tests show that the fracture toughness of the materials on the upper shelf increases with the increasing of strain rate and the ductile-brittle transition temperature elevated, but for HQ100 steel the fracture toughness under 5.54m/s is lower than that under 2.00m/s due to the critical strain rate. In the end a kinetic model for ductile-brittle fracture mode transition behavior is introduced to explain the expetimental results.