Comparison and investigation of mechanical properties of bronze and copper powders compressed by computer-controlled uniaxial die and cold isostatic pressing methods

Turkish Powder Metallurgy Association, TPMA;Gazi UniversityProceedings of the 3rd International Powder Metallurgy Conference --4 September 2002 through 8 September 2002 -- Ankara --Copper and bronze powders have been pressed up to 800 MPa pressure in a computer-controlled uniaxial die and up to 500 MPa in a cold isostatic pressing unit and their densification and microhardness values have been investigated. In the case of medium hardness and plastic behaving copper powders maximum density of %91 and % 94, bronze powders which have more hardness values than copper %81 and %83 was obtained when the pressure has reached up to 800 and 500 MPa in the uniaxial and cold isostatic pressing, respectively. Microhardness values of uniaxilly pressed copper and bronze powders are 116.4 and 192.3 kg/mm 2 under applied pressure of 800 MPa and in cold isostatic pressing these are 103.9 and 172.1 kg/mm2 under the 500 MPa pressure, successively as well. In the analysis conducted by Scanning Electro Microscope, sharp deformations have been observed under the applied pressure on the powders