Solvent and solute diffusion in b.c.c. Ti—Co and Ti—Mn alloys

Abstract

Abstract Measurements by the sectioning method of the self-diffusion coefficient c Ti44 in β TiCo and β TiMn alloys gave the results (in units of cm2 sec−1): Ti 1.6% Co D = 1.26 × 10−3 exp (-34 700/RT)(964°-1504°C)Ti 3.3% Co D = 1.58 × 10−3 exp (-33 500/RT)(893°-1344°C)Ti 4.9% Co D = 1.41 × 10−2 exp (-38 300/RT)(803°-1299°C)Ti 7.4% Co D = 2.50 × 10−2 exp (-38 900/RT)(803°-1211°C)Ti 9.7% Mn D = 1.90 ×10−2 exp (-40 900/RT)(864°-1447°C)Ti 13.3% Mn D = 2.06 × 10−2 exp (-41 100/RT)(803°-1344°C)Ti 17.9% Mn D = 2.60 × 10−2 exp (-42 100/RT)(797°-1297°C)Ti 20.6% Mn D = 5.47 × 10−1 exp (-49 660/RT)(810°-1252°C) The self-diffusion coefficients of Co60 (at 913° and 1205°) and of Mn54 (at 898° and 1240°) were also measured in these same alloys. In pure a Ti the tracer impurity diffusion coefficients of Co60 and Mn54 were measured at 799° and 856°. The results are critically discussed. They comply only in part with common generalization about solute and solvent diffusion in alloys. The solute enhancement of Ti self-dif...