The present invention provides a constituent member of a bearing, which can prolong the life of a ball-and-
roller bearing and can ensure sufficient static
load carrying capacity and dimensional stability; a process for production of the constituent member; and a ball-and-
roller bearing which has a long life and exhibits sufficient static
load carrying capacity and dimensional stability. A workpiece obtained by shaping a steel containing 3.2 to 5.0
mass% of Cr and 0.05 to less than 0.5
mass% of V is subjected to heat treatment such as
carbonitriding, whereby a constituent member of a ball-and-
roller bearing is produced. In the constituent member thus produced, the contents of C and N in the
surface layer extending from the surface of the member to a depth of 10[mu]m fall within the ranges of 1.1-1.6
mass% and 0.1-1.0 mass% respectively; the Vickers
hardness at a depth of 50[mu]m from the surface falls within the range of 740 to 900 (62-67 in terms of Rockwell C
hardness); the content of gamma-iron at a depth of 10[mu]m from the surface falls with the range of 20-55 vol%;
vanadium nitride particles having particle diameters of 0.2-2[mu]m and / or
vanadium carbonitride particles having particle diameters of 0.2-2[mu]m are made present in the
surface layer extending from the surface to a depth of 10[mu]m; and the
area fraction of the particles in the
surface layer extending from the surface to a depth of 10[mu]m falls within the range of 1-10%.