【摘要】 韧脆转变区材料的韧性值呈双峰分布时,用通常的三根试样评定韧性会带来很大的不可信度,本文首次运用概率论和随机模拟方法,详细分析了用矩估计法估计韧性分布为双峰分布时的数学期望的精度和相应的可信度,并结合HQ70、HQ80C钢V缺口Charpy冲击韧性试验在韧脆转变区相应于不同的精度和可信度所需试样的最少个数进行了讨论.更多还原

【Abstract】 The bimodal distribution of the toughness of BCC materials observed at ductile-brittle transition region (DBTR) will cause great suspicion about the confidence of common method to estimate the toughness of material by mean value of three samples at same temperature. In this paper, the, confidence interval and its degree of confidence of expected value of bimodal distribution estimated by sample mean were analysed by probability theory and Monte-Carlo method, and the minimal number of sample required for different confidence interval and degree of confidence is discussed about V notched Charpy impact test of HQ70 and HQ80C HSLA steel at DBTR.更多还原