微小かたさの試験条件に関する研究

抄録

Several experiments of micro-hardness have been performed on A1 and Mg single crystal in order to clarify the effect of test conditions. The micro-hardness increased rapidly at first with the increasing of test load in the small load range, then decreased gradually and became finally independent of the test load. Such phenomena were observed in all the test conditions. Firstly, it was supposed that the increasing phenomenon of micro-hardness in the small load range was caused by the external vibrations which came from the experimental station. Secondly, it was verified that the load-dependency of micro-hardness which show that the micro-hardness decreased with the increasing of test load was due to the heterogeneous deformation of indentation and the dissimilar indentation with respect to the test load. So, the micro-hardness testing have been recomended that the loading speed should be kept about 10 micron/sec and the loading time of indenter kept below 10 sec.