ビッカースくぼみの対角線長さの標準値の決定方法
1967 年 33 巻 392 号 p. 600-605
詳細
1967 年 33 巻 392 号 p. 600-605
At the determination of standard Vickers hardness number, it is one of the most important problem that the diagonal lengths of indentations are determined accuratly, but the absolute length can not be obtained by the ordinary measuring principles.
A new method has been found to determine their absolute values. In this method, the relation between the test load pi and the measured value of diagonal length dij, in which the personal error βj is involved, is given by the following formula;-
dij-βj = (2sin θ/2/Hv) 1/2pi1/n
where θ is the angle included between opposite Faces of Vickers indenter, and Hv is the invariable Vickers hardness of a specimen, and 1/n is a parameter which gives the hardness dependency of the material to indentation load.
The experimental data are verified in conformity to the above formula by using the regression analysis, and thus the absolute value of diagonal length and personal error are estimated by the aid of the least mean square method, and it becomes possible that both the absolute length and individual personal error can be determined with the accuracy of about 0.15μm at confidence coefficient of 95%.
