Abstract: An electrolytic in-process dressing device 10 is provided with a disk-shaped metal-bonded grindstone 2 with a surface 2a with a circular arc shape with a radius R at its outer periphery and a numerical control device 16. The disk-shaped metal-bonded grindstone 2 rotates around an axis Y, and the grindstone is dressed electrolytically while the device 10 grinds the workpiece 1. The numerical control device 16 is provided with a rotary truing device 12 that rotates around the X axis that orthogonally crosses the axis of rotation Y and trues the circular arc surface 2a, a shape measuring device 14 for measuring the shape of the circular arc surface of the grindstone and the shape of the processed surface of workpiece 1 on the machine, and controls the grindstone numerically in the three directions along the axes X, Y and Z. The numerical control device 16 moves the grindstone in three axial directions and repeats the operations of truing, grinding and measurements on-line.

Abstract: An electrolytic in-process dressing device 10 is provided with a disk-shaped metal-bonded grindstone 2 with a surface 2a with a circular arc shape with a radius R at its outer periphery and a numerical control device 16. The disk-shaped metal-bonded grindstone 2 rotates around an axis Y, and the grindstone is dressed electrolytically while the device 10 grinds the workpiece 1. The numerical control device 16 is provided with a rotary truing device 12 that rotates around the X axis that orthogonally crosses the axis of rotation Y and trues the circular arc surface 2a, a shape measuring device 14 for measuring the shape of the circular arc surface of the grindstone and the shape of the processed surface of workpiece 1 on the machine, and controls the grindstone numerically in the three directions along the axes X, Y and Z. The numerical control device 16 moves the grindstone in three axial directions and repeats the operations of truing, grinding and measurements on-line.

Abstract: A fiber-reinforced metal comprising glass fibers and a matrix metal, said glass fibers having a nitrogen content of at least 8 atomic %. The fiber-reinforced metal has a high tensile strength and elasticity.

Abstract: An oxynitride glass, a process for preparing same and a fiber thereof, in the glass which has Si--M.sub.1 --M.sub.2 --O--N system and contains SiO.sub.2, Si.sub.3 N.sub.4 and M.sub.1 O in amounts which, as mole %, satisfy the following equations (a) and (b):(SiO.sub.2 +3Si.sub.3 N.sub.4 +M.sub.1 O) X 100 / (100+2Si.sub.3 N.sub.4)=65 to less than 100 (a)(SiO.sub.2 +3Si.sub.3 N.sub.4)/M.sub.1 O=0.7 to 2.3 (b)wherein M.sub.1 is Ca, or Ca and Mg; M.sub.2 is at least one of the metal selected from the group consisting of Al, Sr, La, Ba, Y, Ti, Zr, Ce, Na, K, Sb, B, Cr, Pb, V and Sn, said glass containing 0-40 mole% SiO.sub.2, 26-70 mole % CaO, 0-20 mole % MgO, and over O to not more than 22 at % M.sub.2.