バイオセラミックスの簡易ねじり強さ試験法の妥当性の検討

抄録

This paper discusses the validity of easy-to-use torsion test method for bioceramics. In this method, a dog-bone type specimen was used, of which gage was 10 mm and its diameter was φ6 mm. The both ends of specimen were fixed in the grip jigs and the upper grip jig was rotated by hand until the specimen was broken. The maximum torque was measured by using an opening torque meter for PET bottles equipped with the lower grip jig. This method, however, should be verified by comparing the torsion strength data by another method, and also by checking no experimenter effect by round robin tests. The former trial was done by using a material testing machine equipped with a convertor from linear motion of the crosshead to rotation for torsion tests. Test samples were 5 types of apatite ceramics with different porosity. The torsion strength data by easy-to-use method agreed well with those by material testing machine method. In the latter trial, 4 organizations participated the round robin tests. The samples were the same as before, but they were immersed in phosphate buffered saline for 24 hr before the torsion tests. The torsion strength data of each organization showed good coincidence for each sample as well. These trails indicate that the easy-to-use torsion test method is effective in practical use.