Annihilation of Positrons in Fe80–xNixB20 Metallic Glasses

Positron Annihilation Study of Structural Relaxation in Amorphous Fe40Ni40B20Alloy

“…On the other hand, conclusive changes in the 57Fe Mössbauer spectra parameters namely in the average hyperfme induction Βef at 57 Fe nuclei and in the 2nd to 1st line intensity ratio (reflecting the average magnetization direction), as well as in the static coercivity He were found in the samples of the same material -amorphous Fe40Νi40B20 alloy and at the same annealing time interval as in the present work [5]. This fact does not confirm the declared sensitivity of positron annihilation to topological and chemical changes due to the annealing of amorphous Fe40Νi40B20 alloys [1,3]. The reason, in our opinion, is the high density of vacancy-like defects both in the as-quenched and in the relaxed amorphous states.…”

“…Balúch et al [2] found the Ni concentration dependence of the PA characteristics for the amorplous Fe80-xΝixB20 (x = 10, 20, 30, 40) alloys; however, Κriśtiakova et al [3] deduced its independence in the same concentration range. Also the changes of PA parameters of the Fe40Νi40B20 alloy due to the structural relaxation and crystallization are rather confusing [1,3]. Wlile de Vries et al [1] state the unchanged positron lifetime after (751) crystallization, Κriśtiakova et al [3] found the 6 % decrease in this alloy and 23% increase in the Fe70Νi10B20 alloy and claimed that the annihilation characteristics in amorphous alloys differ from those in the annealed_ samples in general.…”

“…The aim was to verify the sensitivity of this method to the changes in amorphous Fe40Νi40B20 alloy connected with the annealing out of free volume and possibly with the chemical short-range ordering. As far as Fe40Νi40B20 alloy is concerned, there are some contradictory [1][2][3]. Balúch et al [2] found the Ni concentration dependence of the PA characteristics for the amorplous Fe80-xΝixB20 (x = 10, 20, 30, 40) alloys; however, Κriśtiakova et al [3] deduced its independence in the same concentration range.…”

“…As far as Fe40Νi40B20 alloy is concerned, there are some contradictory [1][2][3]. Balúch et al [2] found the Ni concentration dependence of the PA characteristics for the amorplous Fe80-xΝixB20 (x = 10, 20, 30, 40) alloys; however, Κriśtiakova et al [3] deduced its independence in the same concentration range. Also the changes of PA parameters of the Fe40Νi40B20 alloy due to the structural relaxation and crystallization are rather confusing [1,3].…”

“…Also the changes of PA parameters of the Fe40Νi40B20 alloy due to the structural relaxation and crystallization are rather confusing [1,3]. Wlile de Vries et al [1] state the unchanged positron lifetime after (751) crystallization, Κriśtiakova et al [3] found the 6 % decrease in this alloy and 23% increase in the Fe70Νi10B20 alloy and claimed that the annihilation characteristics in amorphous alloys differ from those in the annealed_ samples in general.…”