以不同硬度的P91钢管件和低合金钢管件作为研究对象,在消除外部因素(试样温度、刚性、质量及表面状况等)导致的误差后,通过硬度对比试验发现,相对于真实布氏硬度值,低硬度P91钢管件的布氏硬度转换值(HBHLD)仍然存在较大负偏差.根据力学性能试验结果,结合里氏硬度检测原理及强化理论,分析了HBHLD值产生偏差的内在原因.结果表明:P91钢管件硬度的降低伴随着固溶强化及位错强化效果的减弱,致使屈强比降低,是导致其HBHLD值出现负偏差的主要原因;弹性模量的微小变化对其影响不大.

The P91 steel pipes and low alloy steel pipes with different hardness values were selected as the research objects to analyze.On the premise of eliminating error caused by environmental factors(such as specimen temperature,rigidity,weight and surface condition),through the hardness comparison test,it was found that the HBHLD value of low hardness P91 steel pipes remained negative deviation compared to the real HBW value.According to the results of the mechanical properties testing,the intrinsic reasons of HBHLD value deviation was analyzed combining Leeb hardness testing principle and the reinforcement theory.The results show that the decrease of hardness of P91 steel pipe accompanied by weakening of solid solution strengthening and dislocation strengthening effects resulted in the decrease of the yield ratio,which was the main reason for the negative deviation of the HBHLD,and the tiny change of elastic modulus had little effect on the deviation.