MECHANICAL ALLOYING OF THE IMMISCIBLE SYSTEM W-CU

The formation of nanocrystalline and amorphous phases in the immiscibl e binary system W-Cu by mechanical alloying was studied. By HRTEM it w as found that the amorphous matrix contains distorted tungsten crystal lites with 1 to 1.5 nm size. In addition, the amorphous phase was foun d at the surface of the original particles. By X-ray analysis, the lat tice parameter of the BCC-W, the relative amount of the amorphous phas e and its atomic environment at different mechanical alloying times ar e studied. Beyond a certain time, MA is found to cause amorphization r ather than increasing the solid solubility.