ISO 5754 specifies the dimensions of an unnotched impact test piece of sintered metal materials. The test piece may be obtained directly by pressing and sintering or by machining a sintered part. ISO 5754 applies to all sintered metals and alloys, with the exception of hardmetals. However, for certain materials (for example, materials with low porosity or materials with high ductility), it may be more appropriate to use a notched test piece which, in this case, will give results with less scatter. (In this case, refer to ISO 148‑1.) NOTE For porous sintered materials, the results obtained from impact tests are not necessarily very accurate compared with results obtained from tests on solid metals.