12Cr1MoV钢动态断裂韧性的试验研究

EXPERIMENTAL STUDY ON DYNAMIC FRACTURE TOUGHNESS OF 12Cr1MoV STEEL

采用Hopkinson压杆装置对试样冲击加载,完成了12Cr1MoV钢在不同温度冲击条件下动态断裂韧性的测试.实验获得了12Cr1MoV钢的KId-t曲线,该曲线具有明显的韧脆转变趋势,存在上平台区、韧脆转变过渡区及下平台区,材料的韧脆转变温度DBTT=-4.3℃.

Dynamic fracture toughness （KId） of 12CrlMoV steel at various temperatures is tested with Hopkinson pressure bar used to impact specimens and liquefied nitrogen and alcohol used to modulate experimental temperature. The impact response curve, that is, KI （T）--T, is established. Fracture initiation time tf is measured with use of the strain gauge. On the impact response curve,KI （t） at the fracture initiation time,that is,KI（tf）,is the very dynamic fracture toughness of material, namely,KId=KI（tf）. By means of experiments,the KId--T curve of 12CrlMoV steel is obtained,which displays obvious ductile-to-brittle transition tendency. It has its upper shelf, ductile-to brittle transition region and lower shelf. The DBTT （ductile-to-brittle transition temperature） of 12CrlMoV steel is --4.3℃.