1993 年 42 巻 473 号 p. 209-213
By using newly developed soft gripping devices, a quite simple and economical test method was realized in tensile tests of engineering ceramics. The gripping device consists of high strength polymer tube and a Duralumin vessel. So long as the testing samples of circular ceramic bar are straight enough, whether machined or not, they can be directly delivered to tensile tests without any special machining of the gripping portions. This simple gripping method will bring in low-cost tensile tests which have never been achieved.
Although the bending effect on the fracture load is often serious in the tensile tests of engineering ceramics, the soft gripping devices were also successful in removing the bending strain. The regulation of JIS for the bending component of the strain, which should be below 10% at a half of specimen's fracture load, was cleared without any labourious work.