The finishing process of advanced ceramic balls can be divided into two steps. The first step is lapping in which most of the stock from the ball is removed at a higher material removal rate. The second step is polishing in which the required ball surface roughness, roundness, dimensional and geometric accuracy are achieved. In polishing, the abrasive particle size is ≤ 1 μm, and the load and s...

The final finishing process of advanced ceramic balls used in hybrid precision bearings constitutes two thirds of the total manufacturing cost, hence the effective and economic finishing methods and processes are critical to their widespread application. A novel eccentric lapping machine is designed and manufactured, Hot Isostatically Pressed (HIPed) silicon nitride ball blanks (diameter 13.25 ...

Based on no-slip cases between steel balls and lapping discs while a horizontal grinding machine is working, the motion equations of the ball lapping are established and the law of motion is revealed by the MATLAB software. This paper shows that the difference of the trace spacing is reduced by increasing the disc diameter, which can make the trace distribution of the steel ball surface more un...

lapping is one of the most important polishing processes which can be used to fabricate flat and smooth surfaces. in this paper, the effect of lapping characteristics and mesh number of abrasive particles are studied on the surface roughness and flatness for the machining of hardened aisi 52100 rings. the most significant lapping characteristics are pressure, lap plate speed and time. scanning ...

This paper reports ductile or partial ductile mode machining of silicon, glass and some advanced ceramics. Results are presented using scanning electron micrographs of the machined surfaces. Grinding and lapping operations using inexpensive machine tools could produce ductile streaks on surfaces of these brittle materials under good conditions. Manufacture of spherical glass lenses by the fract...

The technology of ultra-precision machining, spanning almost three decades, has only in recent years experienced major advances in machine design and, subsequently, performance and productivity. In the 1970’s, ultra-precision machining techniques were successfully adopted for the manufacture of computer memory discs used in hard drives, and also photoreceptor components used in many photocopier...