抄録
The hardness of slow-cooled (at cooling rate 0.57°C/min) and water-quenched Cu-Al-Ni alloys (with 10.0-14.5% Al and 0.0-14.0% Ni) was measured, and the phase in the alloys was observed. And the interrelations of the hardness, the phase, the Aluminium and the Nickel content etc. were studied.
The main results obtained are as follows:
(1) On the slow-cooled specimens the maximum of hardness appears in alloys with 10.0-10.5% Al and about 10% Ni, and in those with above 11.2% Al and 0-2% Ni.
(2) On the water-quenched specimens the hardness of alloys with 10.0-10.5% Al lowers slightly according to the increase of Nickel content, and that of the alloys with above 11.2% Al reaches the maximum at a certain Nickel content. The maximum of alloys with 11.2-13.0% Al migrates to the side with more Nickel content according to the increase of Aluminium content.
(3) The α phase increases and the δ phase decreases according to the increase of Nickel content.
(4) The grain size of the α phase in alloys with below 12.0% Al and rich Nickel content and of the δ phase in those with above 12.0% Al and rich Nickel content become extremely small.
